Field of the invention

The present invention relates to the field of processing industrial waste and other mixed materials, including ores and concentrates, comprising inorganic compounds and eventually organic compounds.

The method of the invention allows to extract valuable organic and inorganic compounds from industrial wastes as well as ores and concentrates.

Background of the invention

Industrial waste has been a problem since the industrial revolution. Indeed, industrial waste may be toxic, ignitable, corrosive or reactive. This waste is generated at every stage in the production process, use and disposal of manufactured products. It is considered as one of the most harmful waste and it is produced in large volumes compared to any other. If improperly managed, this waste can pose dangerous health and environmental consequences. For instance, industrial wastes are often disposed of by drying to reduce moisture and then incinerated or deposited directly as landfill, resulting in significant environmental contamination. Indeed, landfill sites can release toxins such as heavy metals into surrounding ground water tables and organics convert into gases such as methane which pollute the atmosphere.

Disposal of industrial wastes in landfill not only pose a threat to the environment and health of populations but it also reduces the available lands suitable for living and it is a waste of highly valuable compounds such as noble, rare and earth metals that could be extracted from industrial wastes.

Unfortunately, technologies for processing industrial wastes currently on use are largely neglecting to extract valuable compounds from wastes. As a result, the cost for waste processing is often significantly higher in price than the cost of coal, oil shale and other initial products in the production of which they were formed. This is clearly limiting the development of industrial wastes processing in the countries that do not benefit of strong support programs.

For example, in the coal-related energy industry, tons of gypsum and pyrite wastes are annually produced. Pyrite contains heavy metals such as arsenic, cobalt, copper, lead, nickel, and zinc. When pyrite wastes are exposed to air and ground water or rain in impoundments, it readily oxidizes, forming large amounts of acid and releasing soluble toxic substances that pollute land and water sources.

Another example is the carbon black obtained by pyrolysis of used tires. Carbon black is a valuable raw material that can be used as a filler in rubber products and plastics. The cost of production of carbon black by pyrolysis of used tires is significantly lower than by the classic method that relies on burning natural gas. However, carbon black obtained by the pyrolysis method contains many impurities (inorganic compounds), usually from 10 to 15% by weight. Unfortunately, this high percentage of impurities, makes it impossible to use it as a raw material in the production of rubber, pigments and high-tech products.

Thus, there is still nowadays a strong need for a method of treatment of a wide range of waste materials such as industrial wastes in order to minimize landfill and atmospheric pollution, to protect populations and to extract valuable elements such as highly pure carbon black or valuable inorganic compounds such as expensive oxides and noble metals. The present invention meets these and other needs.

Summary of the invention

In search for a method of purification of pyrolysis carbon black obtained during the disposal of used tires, the inventors successfully developed a method of treatment that does not only apply to carbon black purification but allows to purify the organic fraction and a wide range of inorganic compounds from industrial wastes and other materials comprising a mixture of organic and inorganic compounds.

Thus, in a first aspect, the invention relates to a method for purifying at least one fraction or compound of interest from a starting material comprising at least two inorganic compounds or at least one inorganic compound and at least one organic compound, wherein the method comprises at least one cycle of the following steps: a) a fluorination treatment of the starting material or of a material derived from said starting material; followed by b) a hydrochloric acid treatment of a material fluorinated in a).

Preferably, the reagents used during the cycles of fluorination/hydrochloric acid treatments, preferably NH4F and HCI, are at least about 95% regenerated, preferably at least about 97% regenerated, more preferably at least about 99% regenerated, even pore preferably at least about 99.9% regenerated.

In a preferred embodiment, the method of the invention further comprises at least one sorption treatment of the material resulting from the last cycle of fluorination/hydrochloric acid treatments.

Preferably, the fluorination treatment(s), the hydrochloric acid treatment(s), and the sorption treatment(s) are done in an aqueous solvent.

In another preferred embodiment, at least one ultrasonic cavitation is applied during a treatment selected from the list consisting in fluorination treatment, hydrochloric acid treatment and sorption treatment. Preferably, an ultrasonic cavitation is applied during each fluorination, chlorination and sorption treatments.

In yet another preferred embodiment, the method of the invention further comprises a step of nanoshredding of the starting material prior to the first fluorination or of a material to be subjected to a sorption treatment.

Preferably, the method of the invention takes place at a temperature comprised between about 10°C and about 100°C, more preferably at a temperature comprised between about 15°C and about 50°C, even more preferably at a temperature of about 20°C.

Preferably, the starting material according to the method of the invention is selected from the list consisting in carbon black, for example carbon black obtained by pyrolysis of tires such as used tires, coal ashes, pyrite cinders, shale ashes, for example oil shale ashes, brown coal, industrial solid waste such as waste of copper-nickel industry, of titanium-magnesium industry, and of zinc industry, lithium-ion batteries, ores including native, meteoritic and processed ores, such as uranium ores, gold ores, silver ores, platinum ores, tin ores, copper ores, nickel ores, iron ores, arsenic ores, manganese ores, lead ores, zinc ores, cobalt ores, antimony ores, aluminum ores, phosphate ores, including phosphorite and apatite ores, sulfides ores, and polymetallic ores including any combination of metallic ores thereof such as copper-nickel ores and lead-zinc ores, industrial waste from ores processing such as slag ores, including slag ores of any of the above mentioned ores, copper concentrates, limestone-like materials, electronic circuit boards, waste containing copper alloy, copper alloy dust, preferably copper alloy dust with a metal content of at least about 50%, waste containing bronze, bronze dust, preferably bronze dust with a metal content of at least about 50%, waste containing brass, brass dust, preferably brass dust with a metal content of at least about 50%, or a mixture thereof. In a particular embodiment, the starting material according to the method of the invention is carbon black, preferably a carbon black having a purity below about 96 %, more preferably below about 90%.

In still a preferred embodiment, the at least one fraction or compound of interest according to the method of the invention comprises the organic fraction of the starting material, preferably the at least one fraction or compound of interest is the organic fraction of the starting material. Preferably, the at least one fraction or compound of interest comprises at least one inorganic compound of the starting material, preferably several inorganic compounds of the starting material, even more preferably all the inorganic compounds of the starting material.

In a preferred embodiment, the inorganic compound(s) according to the method of the invention is (are) selected from the list consisting in oxides such as silicon dioxide or silica or SiOz, aluminum oxide or alumina or AI2O3, iron(lll) oxide or ferric oxide or read lead or FezCh, calcium oxide or quicklime or CaO, magnesium oxide or MgO, potassium oxide or K2O, sodium oxide or NazO, sulfur trioxide or SO3, phosphorous pentoxide or P2O5, titanium dioxide or TiOz, strontium oxide or SrO, manganese(ll) oxide or MnO, barium oxide or BaO, arsenic trioxide or AS2O3, chromium(ll) oxide or CrzCh, zirconium(IV) oxide or ZrOz, copper(ll) oxide or CuO, vanadium(V) oxide or V2O5, tin dioxide or SnOz, cerium(IV) oxide or CeOz, zinc oxide or ZnO, coba lt( 11, III) oxide or cobalt tetraoxide or CO3O4, Nickel(ii) oxide or NiO, lanthanum oxide or LazOs, rubidium oxide or RbzO, bismuth(lll) oxide or BizOs, plutonium dioxide or PuOz, platinum oxide or PtOz, rhenium(VII) oxide RezO?, yttrium(lll) oxide or Y2O3, neodymium(lll) oxide or NdzCh, lead (II) oxide or PbO, and tungsten(VI) oxide or tungsten trioxide or WO3; phosphorous halides in particular trihalides according to the formula PX3 or pentahalides according to the formula PX5, phosphorous (II) halides such as halides according to the formula P2X4, oxyhalides such as halides according to the formula POX3, thiohalides such as halides according to the formula PSX3, and selehalides such as halides according to the formula PSeXs, wherein the 3, 4 or 5 X are elements selected from the list consisting in Fluor or F, Chlorine or Cl, Bromine or Br, Iodine or I, or any combination thereof; calcium carbonate or CaCCh; noble metals such as ruthenium or Ru, rhodium or Rh, palladium or Pd, silver or Ag, osmium or Os, iridium or Ir, platinum or Pt, and gold or Au; alkaline earth metals such as beryllium or Be, magnesium or Mg, calcium or Ca, strontium or Sr, barium or Ba, and radium or Ra; rare earth metals such as cerium or Ce, dysprosium or Dy, erbium or Er, europium or Eu, gadolinium or Gd, holmium or Ho, lanthanum or La, lutetium or Lu, neodymium or Nd, praseodymium or Pr, promethium or Pm, samarium or Sm, scandium or Sc, terbium or Tb, thulium or Tm, ytterbium or Yb, and yttrium or Y; Chlorine or Cl, cesium or Cs, zinc or Zn, titanium or Ti, silicon or Si, phosphorous or P, sulfur or S, copper or Cu, iron or Fe, sodium or Na, cobalt or Co, aluminum or Al, iodine or I, manganese or Mn, potassium or K, molybdenum or Mo, rhenium or Re, bromine or Br, lead or Pb, bismuth or Bi, cadmium or Cd, strontium or Sr, germanium or Ge, nickel or Ni, indium or In, antimony or Sb, mercury or Hg, thorium or Th, uranium or U, tungsten or W, americium or Am, vanadium or V, gallium or Ga, niobium or Nb, tantalum or Ta, and Arsenic or As, more preferably, the inorganic compounds according to the invention are selected from the list consisting in silicon dioxide or silica or SiOz, aluminum oxide or alumina or AI2O3, copper or Cu, iron or Fe, gold or Au, platinum or Pt, silver or Ag, germanium or Ge, titanium or Ti, calcium oxide or quicklime or CaO, phosphorus P, calcium carbonate or CaCCh, and iron(lll) oxide or ferric oxide or red lead or FezCh.

In a second aspect, the invention also relates to a carbon black analog obtained by purification of a brown coal having a percentage of ash of at least 20% with the method according to the invention as described above, wherein said carbon black analog has a carbon purity of at least about 99.7%, does not contain any sulfur, has a density of about 1 g/cm3 and is harder than carbon black.

In a third aspect, the invention further relates to a method to convert exhaust gas CO2 into CaCCh, said method comprising the following steps: a) Purification of CaO with the method according to the invention as described above with a starting material, such as oil shale ashes, comprising CaO; b) Decarbonization of exhaust gases by successively applying a leaching treatment, a cooling treatment and a slaked lime treatment, wherein the obtained material is an inorganic material comprising CaCOs and other inorganic compounds; c) Purification of CaCOswith the method according to the invention as described above with the material obtained in b) as a starting material; d) Optionally, purification of other inorganic elements present in the material obtained in b), such as noble metals and/or rare earth metals, with the method according to the invention as described above.

Brief Description of the drawings

Figure 1: Diagram representing a typical sequence of events according to the method of the invention. Detailed Description of the Invention

The inventors have developed a method that allows to purify the organic fraction and/or the inorganic compounds of a material comprising a mixture of inorganic compounds and eventually organic compounds. The method of the invention is applicable to a wide range of industrial wastes and allows to minimize landfill and atmospheric pollution, but also to protect populations from its consequences. Moreover, the method of the invention allows to extract valuable elements from industrial wastes such as highly pure carbon black or valuable inorganic compounds such as expensive oxides and noble or rare earth metals. This invention is not limited to industrial wastes treatment. Indeed, the method of the invention can be applied to any material comprising a mixture of inorganic compounds or a mixture of inorganic and organic compounds.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skills in the art to which the present application belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, representative methods and materials are herein described.

Unless otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about". As used herein, the term "about" when referring to a measurable value such as an amount of weight, time, dose, percentage, etc. is meant to encompass in one example variations of ± 20%, preferably ± 10%, more preferably ± 5%, alternatively ± 2%, still alternatively ± 1% and yet alternatively ± 0,1% from the specified amount. For example, "about 20" include all the values ranging from ± 5% of 20, i.e. a range of values from 19 to 21.

In a first aspect, the invention relates to a method for purifying at least one fraction or compound of interest from a starting material comprising at least two inorganic compounds or at least one inorganic compound and at least one organic compound, wherein the method comprises at least one cycle of the following steps: a) a fluorination treatment of the starting material or of a material derived from said starting material; followed by b) a hydrochloric acid treatment of the material fluorinated in a).

As used herein, the term "material" may refer to a mixture of one or several inorganic compounds and/or one of several organic compounds in a solid and/or liquid state and/or gaseous state (for example plant exhaust gas).

As used herein the term "starting material" refers to any mixture of at least two inorganic compounds or a mixture of at least one inorganic compound and at least one organic compound.

As used herein, the term "material derived from said starting material" refers to any material resulting from one or several treatment(s) of said "starting material". Indeed, the starting material can be modified by an additional step of pre-treatment prior to step a) and, in case of several cycles of steps a) and b), the material entering the second cycle and followings has been modified by previous cycles of fluorination/hydrochloric acid treatments when entering a new cycle.

As used herein, the term "inorganic compound" or "inorganic substance" are equivalent and can be used one for the other, they refer to any chemical compound or substance that lacks carbon-hydrogen bonds. The inorganic compound according to the invention can be any inorganic compound. In a preferred embodiment, the inorganic compound according to the invention is selected from the list consisting in oxides such as silicon dioxide or silica or SiOz, aluminium oxide or alumina or AI2O3, iron ( 111 ) oxide or ferric oxide or read lead or FezCh, calcium oxide or quicklime orCaO, magnesium oxide or MgO, potassium oxide or K2O, sodium oxide or NazO, sulfur trioxide or SO3, phosphorous pentoxide or P2O5, titanium dioxide or TiOz, strontium oxide or SrO, manganese(ll) oxide or MnO, barium oxide or BaO, arsenic trioxide or AS2O3, chromium(ll) oxide or CrzCh, zirconium(IV) oxide or ZrOz, copper(ll) oxide or CuO, vanadium(V) oxide or V2O5, tin dioxide or SnOz, cerium(IV) oxide or CeOz, zinc oxide or ZnO, coba lt( 11, III) oxide or cobalt tetraoxide or CO3O4, Nickel(ii) oxide or NiO, lanthanum oxide or LazOs, rubidium oxide or RbzO, bismuth(lll) oxide or BizOs, plutonium dioxide or PuOz, platinum oxide or PtOz, rhenium(VII) oxide RezO?, yttrium(lll) oxide or Y2O3, neodymium(lll) oxide or NdzCh, lead (II) oxide or PbO, and tungsten(VI) oxide or tungsten trioxide or WCh phosphorous halides (or Px) in particular trihalides according to the formula PX3 or pentahalides according to the formula PX5, phosphorous (II) halides such as halides according to the formula P2X4, oxyhalides such as halides according to the formula POX3, thiohalides such as halides according to the formula PSX3, and selehalides such as halides according to the formula PSeXs, wherein the 3, 4 or 5 X are elements selected from the list consisting in Fluor or F, Chlorine or Cl, Bromine or Br, Iodine or I, or any combination thereof; calcium carbonate or CaCCh; noble metals such as ruthenium or Ru, rhodium or Rh, palladium or Pd, silver or Ag, osmium or Os, iridium or Ir, platinum or Pt, and gold or Au; alkaline earth metals such as beryllium or Be, magnesium or Mg, calcium or Ca, strontium or Sr, barium or Ba, and radium or Ra; rare earth metals such as cerium or Ce, dysprosium or Dy, erbium or Er, europium or Eu, gadolinium or Gd, holmium or Ho, lanthanum or La, lutetium or Lu, neodymium or Nd, praseodymium or Pr, promethium or Pm, samarium or Sm, scandium or Sc, terbium or Tb, thulium or Tm, ytterbium or Yb, and yttrium or Y; Chlorine or Cl, caesium or Cs, zinc or Zn, titanium or Ti, silicon or Si, phosphorous or P, sulfur or S, copper or Cu, iron or Fe, sodium or Na, cobalt or Co, aluminium or Al, iodine or I, manganese or Mn, potassium or K, molybdenum or Mo, rhenium or Re, bromine or Br, lead or Pb, bismuth or Bi, cadmium or Cd, strontium or Sr, germanium or Ge, nickel or Ni, indium or In, antimony or Sb, mercury or Hg, thorium or Th, uranium or U, tungsten or W, americium or Am, vanadium or V, gallium or Ga, niobium or Nb, tantalum or Ta, and Arsenic or As. More preferably, the inorganic compounds according to the invention are selected from the list consisting in silicon dioxide or silica or SiOz, aluminum oxide or alumina or AI2O3, copper or Cu, iron or Fe, gold or Au, platinum or Pt, silver or Ag, germanium or Ge, titanium orTi, calcium oxide or quicklime or CaO, phosphorus P, calcium carbonate or CaCCh, and iron(lll) oxide or ferric oxide orred lead or FezCh.

As used herein, the term "organic compound" or "organic substance" are equivalent and can be use one for the other, they refer to any chemical compound or substance that contains carbon-hydrogen bonds.

The starting material according to the invention can be any mixture of at least two inorganic compounds or any mixture of at least one inorganic compound and at least one organic compound. The starting material according to the invention comprise an inorganic fraction and may also comprise an organic fraction.

As used herein, the term "inorganic fraction" refers to the fraction of a material consisting only in the inorganic compounds present in said material. The inorganic fraction according to the invention comprises at least one inorganic compound. The inorganic fraction of the starting material may comprise only one inorganic compound when there is an organic fraction as well in the starting material. The inorganic fraction of the starting material comprises at least two inorganic compounds when there is no organic fraction in the starting material. Preferably the inorganic fraction of the starting material comprises at least 2, 3, 4, 5, 6, 7, 8, 9, 10 inorganic compounds.

As used herein, the term "organic fraction" refers to the fraction of a material consisting only in the organic compounds present in said material. When present, the organic fraction of the starting material comprises at least one organic compound. Preferably, the organic fraction of the starting material comprises several organic compounds, for example 2, 3, 4, 5, 6, 7, 8, 9, 10 organic compounds.

In a preferred embodiment, the starting material according to the invention is selected from the list consisting in carbon black, for example carbon black obtained by pyrolysis of tires such as used tires, coal ashes, pyrite cinders, shale ashes, for example oil shale ashes, brown coal, industrial solid waste such as waste of copper-nickel industry, of titanium-magnesium industry, and of zinc industry, lithium-ion batteries, ores including native, meteoritic and processed ores, such as uranium ores, gold ores, silver ores, platinum ores, tin ores, copper ores, nickel ores, iron ores, arsenic ores, manganese ores, lead ores, zinc ores, cobalt ores, antimony ores, aluminum ores, phosphate ores, including phosphorite and apatite ores, sulphides ores, and polymetallic ores including any combination of metallic ores thereof such as copper-nickel ores and lead-zinc ores, industrial waste from ores processing such as slag ores, including slag ores of any of the above mentioned ores, copper concentrates, limestone-like materials, electronic circuit boards, waste containing copper alloy, copper alloy dust, preferably copper alloy dust with a metal content of at least about 50%, waste containing bronze, bronze dust, preferably bronze dust with a metal content of at least about 50%, waste containing brass, brass dust, preferably brass dust with a metal content of at least about 50%, or a mixture thereof.

Table IX provides examples of composition of different starting materials.

As used herein, the term "carbon black" refers initially to a material produced by the incomplete combustion of heavy petroleum products such as FCC tar, coal tar, or ethylene cracking tar. "Carbon black" refers also to a material produced by pyrolysis of used tires. "Carbon black" refers to a form of paracrystalline carbon that has a high surface-area-to-volume ratio, albeit lower than that of activated carbon. It is dissimilar to soot in its much higher surface-area- to-volume ratio and significantly lower (negligible and non-bioavailable) polycyclic aromatic hydrocarbon (PAH) content. Carbon black is mainly used as a reinforcing filler in tires and other rubber products. In plastics, paints, and inks, carbon black is used as a color pigment.

As used herein, the term "coal ash" refers to the waste that is left after coal is combusted. It includes fly ash (fine powdery particles that are carried up the smokestack) as well as coarser materials that fall to the bottom of the furnace. Most coal ash comes from coal-fired electric power plants.

As used herein, the term "pyrite cinder" or "pyrite ash" are equivalent and referto a waste product from the production of sulfuric acid. Pyrite cinders are often rich in trace metals such as Zn, Pb, Cu and Cd.

As used herein, the term "oil shale ash" refer to ashes produced by the combustion of oil shale. Oil shale is a type of sedimentary rock formation that can be used to produce oil and gas. Oil shale ashes have a very diverse mineral composition.

As used herein, the terms "lignite" and "brown coal" are equivalent and refer to aa soft, brown, combustible, sedimentary rock formed from naturally compressed peat. It is considered the lowest rank of coal due to its relatively low heat content. It has a carbon content around 20- 35% percent. It is mined all around the world, used almost exclusively as a fuel for steam-electric power generation. It is the coal that is the most harmful to health.

As used herein, the term "ore" refers to a rock that contains one or more valuable minerals. As used herein, the term "native ore" refers to an igneous or sedimentary rock that contains a metal element in its pure state. For example, gold, tin, copper, and platinum may be found in their metallic states in veins or alluvial deposits. As used herein the term "meteoritic ore" refers to a metallic-type meteorite containing small pieces of metal such as iron, nickel, cobalt, arsenic, or manganese. As used herein, the term "processed ore" refers to an ore processed by a plant in order to concentrates the metal part. As used herein the term "slag waste" refers to the glass-like by-product left over after a desired metal has been separated from its raw ore.

As used herein, the term "copper concentrate" refers to a material having a copper content of about 30% by weight. The remainder consists mostly of sulfur and iron. Copper concentrates are made mostly from sulfide ores. Ores extracted from overseas mines have a typical grade of about 1%. The ores are then "dressed" at the mine to increase the purity and produce concentrate. They are used as raw materials in copper smelting. As used herein the terms "limestone-like material" and "chalk-like material" are equivalent and can be used for one another, they refer to a material comprising mainly CaCCh. The limestone-like material is obtained during the decarbonization of plant gas exhaust as described later in the description (cf. application VIII). This material also contains other inorganic elements trapped together with CO2 during the decarbonization process.

The invention relates to a method for purifying at least one fraction or compound of interest from the starting material.

As used herein, the term "purifying" or "extracting" are equivalent and can be used one for the other and refer to the physical separation of a compound or of a fraction of interest from other fractions or compounds present in the same material, for example the starting material according to the invention. A purified fraction or compound comprises at least about 50%, 60%, 70%, 80%, 90%, 95% of said fraction or compound. Preferably, a purified fraction or compound comprises at least about 95%, 96%, 97%, 98%, 99% of said fraction or compound. Even more preferably, a purified fraction or compound comprises at least about 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, 99.9% of said fraction or compound.

In a preferred embodiment, the invention relates to the purification of the organic fraction of the starting material.

In another preferred embodiment, the invention relates to the purification of at least one inorganic compound, preferably at least two inorganic compounds, more preferably 3, 4, 5, 6, 7, 8, 9, 10 inorganic compounds of the starting material. In a particular embodiment, the invention relates to the purification of all the inorganic compounds of the starting material.

In yet another embodiment, the invention relates to the purification of the organic fraction of the starting material and at least one inorganic compound, preferably at least two inorganic compounds, more preferably 3, 4, 5, 6, 7, 8, 9, 10 inorganic compounds of the starting material. In a particular embodiment, the invention relates to the purification of the organic fraction of the starting material and the purification of all the inorganic compounds of the starting material.

The invention relates to a method comprising at least one cycle of the following steps: a) a fluorination treatment of the starting material or of a material derived from said starting material; followed by b) a hydrochloric acid treatment of a material fluorinated in a).

The material entering a given cycle of fluorination/hydrochloric acid treatment can be a material that has already been modified by a pre-treatment and/or by one or several cycles of fluorination/hydrochloric acid treatments.

As used herein, the term "pre-treatment" and "pre-1 stage" are equivalent and can be used one for the other, they refer to any treatment of the starting material that takes place prior to the first fluorination treatment. The goal of such pre-treatment is to prepare the starting material for the first cycle of fluorination/hydrochloric acid treatment. A pre-treatment is not always needed, depending on the starting material and on the fraction/compounds that are to be extracted. A pre-treatment that can be advantageous is nanoshredding.

As used herein, the term "nanogrinding" or "nanoshredding" are equivalent and can be used one for the other, they refer to the shredding of a material to the nano range, preferably to a particle size ranging from about 1 nm to about 1 pm, more preferably to a particle size ranging from about 10 nm to about 100 nm, even more preferably to a particle size of about 50 nm. Nanoshredding may be obtained by using a mill and preferably takes place in a neutral gaseous medium, such as CO2.

Different other pre-treatments may be performed according to the nature of the starting material and to the fractions and/or compounds that are to be extracted. For example, for carbon black obtained by pyrolysis of used tires, a degreasing pre-treatment, such as an acetone pretreatment, may be necessary. After acetone treatment, the resulting material can be further filtered/wash/filtered prior to the fluorination treatment. For coal, shale ashes, pyrite cinders and phosphorite ores, a pre-treatment consisting in a cycle of mining/filtration/crushing/grinding may be necessary. Grinding or shredding, when not referring to nanogrinding, usually means a grinding to a particle ranging from about 1 pm to about 100 pm, more preferably to a particle size ranging from about 1 pm to about 10 pm. Pre-treatment of coal ashes may further comprise flotation to collect unburned coal and magnetic separation of Fes04. For brown coal, in order to extract hydrocarbon black, a nanoshredding treatment may be necessary. For ashes of settling ponds such as coal and shale ashes, a hydraulic mining from the bottom of the pond followed by flushing, drying and grinding treatments may be necessary. For pyrite cinders a pre-treatment consisting in a cycle of mining/crushing/cleaning/grinding may be necessary. For copper concentrates, a shredding pre-treatment may be needed. Those examples are of course not limiting and are given only to illustrate the diversity of the possible pre-treatments. Pre- treatments are further described in "Application I to VIII" below. The diagram of figure 1 is also providing examples of possible pretreatments.

The number of fluorination/hydrochloric acid treatments cycles to be performed rely on the desired purity of said fraction and/or compounds to be extracted as well as the initial purity of these fraction and/or compounds in the starting material. In a preferred embodiment, the method of the invention comprises between 1 and about 15 cycles of fluorination/hydrochloric acid treatments, preferably between 1 and about 10 cycles of fluorination/hydrochloric acid treatments, more preferably between 1 and about 5 cycles of fluorination/hydrochloric acid treatments. For example, the method of the invention comprises 1, 2, 3, 4 or 5 cycles of fluorination/hydrochloric acid treatments.

As used herein, the term "fluorination treatment" refers to the addition of a fluorination agent to the starting material or to a material derived from said starting material. A fluorination agent can be selected from the list consisting in ammonium fluoride or NH4F, Hydrofluoric acid or HF, fluoride or F-, and potassium fluoride or KF, or a mixture thereof. For the fluorination treatment according to the invention, the ammonium fluoride or NH4F is much preferred. The fluorination treatment takes place at a temperature comprised between about 5°C and about 180°C, preferably at a temperature comprised between about 10°C and about 90°C depending on the compound to be fluorinated, more preferably at a temperature comprised between 20°C and 90°C, for example at a temperature of about 20°C. The fluorination treatment takes place at a pressure of about 1 atm. Preferably the fluorination treatment is done in an aqueous solvent. Preferably, the proportion of starting material: fluorination agent: water is comprised between about 1:4:10 and about 1:1:3. For example, the proportion of starting material: fluorination agent: water is of about 1:4:10 or of about 1:4:8 or of about 1:1:3. Preferably the fluorination agent is present in the aqueous solution at a concentration comprised between about 0.01 and about 1 g/ml, preferably at a concentration comprised between about 0.1 and about 0.5 g/ml, and more preferably at a concentration of about 0.33 g/ml. Preferably the duration of the fluorination treatment is comprised between about 2 h and 12 h, more preferably between about 4 h and about 8 h, even more preferably the duration of the fluorination treatment is of about 6h. During the fluorination treatment, all the inorganic compounds except noble metals, heavy metals, and rare earth metals will be fluorinated. With NH4F as the fluorination agent, the fluorination will take place according to the following general equation:

ROH + n NH ₄ F ->RF _n + H ₂ 0 + n NH ₃ wherein ROH is an oxide inorganic compound, and n a positive integer comprised between 1 and 10, preferably between 1 and 5.

In a preferred embodiment, a cavitation is applied to the material during the fluorination treatment. As used herein, the term "cavitation" or "ultrasonic cavitation" are equivalent and can be used one for another, they refer to the use of ultrasonic cavitation devices to generate high intensity and low frequency ultrasounds in order to enhance various chemical and physical processes such as reaction initiation and mixing, in a liquid medium. Preferably, the cavitation is applied during the all duration of the fluorination treatment. The cavitation can be performed at a frequency of 20,000 Hertz with a cavitation device having an emitting area of 8 to 10 m ² per liter of water.

After a fluorination treatment and before a hydrochloric acid treatment, the fluorinated material, can be filtered and/or washed. Preferably, the fluorinated material is filtered and washed. For instance, the fluorinated material can be filtered, for example with a vacuum filter, then washed one or two times, for example with distilled water, and then filtered again.

Some fluorinated compounds can be directly converted into oxides by hydrolysis in water. In that case no hydrochloric acid treatment is needed for these compounds. It is for example the case of silicon fluoride, aluminum and iron fluorides.

As used herein, the terms "hydrochloric acid treatment" or "HCI treatment" or "Chlorination" are equivalent and can be used one for another, they refer to the addition of hydrochloric acid to the fluorinated material. The HCI treatment takes place at a temperature comprised between about 5°C and about 180°C, preferably at a temperature comprised between about 10°C and about 90°C, more preferably at a temperature comprised between 15°C and 30°C, even more preferably at a temperature of about 20°C. The HCI treatment takes place at a pressure of about 1 atm. Preferably the HCI treatment is done in an aqueous solvent. Preferably the HCI is present in the aqueous solution at a concentration comprised between about 5% and about 35%, preferably at a concentration comprised between about 10% and about 25%, and more preferably at a concentration of about 20%. Preferably the duration of the HCI treatment is comprised between about 6 h and about 48 h, more preferably between about 12 h and about 36 h, even more preferably the duration of the fluorination treatment is of about 24 h. During the HCI treatment, all the inorganic compounds except noble metals, heavy metals, and rare earth metals will be modified according to the following general reaction:

RF _n + n HCI ->RCIn + n HF wherein R is an inorganic compound, and n a positive integer comprised between 1 and

10, preferably between 1 and 5.

In a preferred embodiment, a cavitation is applied to the material during the hydrochloric acid treatment. The cavitation is as described above for the fluorination treatment. Preferably, the cavitation is applied during the all duration of the HCI treatment.

Optionally, the HCI treatment can be done in presence of ammonia (NH3), preferably at about 25% of concentration, hydrazine hydrate (N2H4), preferably of grade "h", soda ash (NazCOs), preferably of technical grade, potassium hydroxide (KOH), preferably of technical grade, magnesium oxide (MgO), preferably of technical grade, calcium oxide (CaO), preferably of technical grade, hydrofluoric acid (HF), preferably at about 50%, oxalic acid (C2H2O4), preferably at 0.03 %, or a mixture thereof.

The HCI treatment can be coupled with the reduction of hydroxydes.

For other compounds a hydrochloric acid treatment is needed. In rare cases, a sulfuric acid treatment will be preferred, for example to take ca re of CaF2 according to the following formula:

CaF2 + H2SO4 = CaSO4 + 2HF

Prior to another cycle of fluorination/hydrochloric acid treatment, the material resulting from the previous cycle can be filtered and/or washed. Preferably, the material is filtered and washed. For instance, the material can be filtered, for example with a vacuum filter, then washed one or two times, for example with distilled water, and then filtered again.

After the last cycle of fluorination/hydrochloric acid treatments, the different materials resulting from the last cycle can be subjected to a post-treatment. As used herein, the term "posttreatment" refers to any treatment of materials resulting from the last cycle of fluorination/hydrochloric acid treatment and prior to an optional sorption treatment.

A post-treatment may comprise a filtration and/or a washing treatment. Preferably, the material resulting from the last cycle of fluorination/hydrochloric acid treatments is filtered and washed. For instance, the material can be filtered, for example with a vacuum filter, then washed one or two times, for example with distilled water, and then filtered again.

After the last filtration, the obtained solid precipitate, can be dried, for example at a temperature of about 100°C for about 2 hours. According to the composition of the solid precipitate, other temperature can be applied, such as room temperature (about 20°C). Eventually, stirring the solid precipitate can accelerate the drying.

In a preferred embodiment, the reagents used during the cycles of fluorination/HCI treatments, i.e. preferably NF F and HCI, are completely regenerated avoiding potential emissions of toxic compounds into the sewage system and the atmosphere. By "completely regenerated", it is intended that at least about 80%, preferably at least about 90%, more preferably at least about 95%, still more preferably at least about 99%, yet more preferably at least about 99.9%, and even more preferably at least about 99.99% of the solvent NF F and HCI are recovered.

The recovered solvent can be reused for further cycles of fluorination/HCI treatments, thereby importantly reducing the cost of the method of the invention.

To regenerate NH4F, the gaseous NH3 and the HF produced during the cycles of fluorination/HCI treatments are collected and put together allowing the following reaction to take place: NH ₃ + HF -> NH ₄ F.

To regenerate HCI, the solution comprising the chlorides of inorganic compounds is heated in order to separate the Cl- from the inorganic compounds and to regenerate HCI according to the following formula: R-CI2 + H2O ->2 HCI + R-O.

In a preferred embodiment, the hydroxides of inorganic compounds obtained when regenerating HCI are converted either to oxides, either to pure chemical elements. After purification of each inorganic compound, the inorganic compound can be washed and/or filtered. The inorganic compound can also be dried before packaging.

After the last filtration and optionally the drying, the resulting material can be subjected to a nanogrinding treatment prior to sorbent treatment(s). The nanogrinding treatment is as described above.

In a preferred embodiment, the method comprises, after the last cycle of fluorination/hydrochloric acid treatment, and optionally a post treatment of the resulting material, at least one sorption treatment of the resulting material.

As used herein, the term "sorption treatment" refers to the use of a sorbent to attach a sorbate from the material submitted to the sorption treatment. Said sorbate is therefore isolated from the rest of the material submitted to the sorption process and can be purified. The sorption treatment takes place at a temperature comprised between about 5°C and about 180°C, preferably at a temperature comprised between about 10°C and about 100°C, more preferably at a temperature comprised between 15°C and 30°C, even more preferably at a temperature of about 20°C. The sorption treatment takes place at a pressure of about 1 atm. Preferably the sorption treatment is done in an aqueous solvent.

The number of sorption cycles to be performed rely on the amounts of sorbates and the purity requirements for the final products as well as on the number of different sorbates to be purified. Preferably, one sorbate is purified per cycle. In a preferred embodiment, the method of the invention comprises between 1 and about 20 cycles of sorption treatments, preferably between 1 and about 15 cycles of sorption treatments, more preferably between 1 and about 10 cycles of sorption treatments. For example, the method of the invention comprises 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10 cycles of sorption treatments.

In a preferred embodiment, a cavitation is applied to the material during the sorption treatments. The cavitation is as described above for the fluorination treatment. Preferably, the cavitation is applied during the all duration of the sorption treatments.

Sorption treatments can be used to purify, among others, noble metals, heavy metals, and rare earth metals.

To purify noble metals, is it possible to use polydithiopropane and derivatives. The use of polydithiopropane for the sorption of noble metals is disclosed in the patent RU2134307. All the sorbent and sorption methods described in RU2134307 are herein incorporated by reference.

Ion exchange resins can also be used to perform sorption treatments, especially for sorption of heavy metals and rare earth metals. Such ion exchange resins are described on the website of Axionit (https://axion-rnm.com/en/production), the content of which being incorporated herein by reference. For example, chelating ion exchange resins can be used to extract scandium, ruthenium, silver, indium, antimony, mercury, lead, and bismuth; strong base ion exchange resins can be used to extract thorium, and uranium; medium basic ion exchange resins can be used to extract copper; low basic ion exchange resins can be used to extract rhodium, palladium, tungsten, rhenium, and iodine; ion exchange resins for the extraction of rare earth metals can be used to extract the sum of heavy REM, for the separation of REM and to extract molybdenum, cadmium, cesium, lanthanum, americium, cerium, praseodymium, neodymium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium; ion exchange resins for precious metal recovery can be used to recover silver, platinum, palladium, gold, ruthenium, rhodium, iridium; Ion exchange resins and sorbents for the recovery of other metals such as lithium extraction ion exchange resin, vanadium extraction ion exchange resin, cobalt extraction ion exchange resin, nickel extraction ion exchange resin, zinc extraction ion exchange resin, gallium extraction ion exchange resin, germanium extraction ion exchange resin, arsenic extraction ion exchange resin, strontium extraction ion exchange resin, yttrium extraction ion exchange resin, molybdenum extraction ion exchange resin, cadmium extraction ion exchange resin, cesium extraction ion exchange resin, lanthanum extraction ion exchange resin, and americium extraction ion exchange resin.

During sorption treatments, fluorine, hydrochloric acid and other acids such as hydrofluoric acid or oxalic acid can also be added to the sorbents to facilitate the sorption processes.

Between each cycle of sorption treatment, the material resulting from the previous cycle can be filtered and/or washed. Preferably, the material is filtered and washed. For instance, the material can be filtered, for example with a vacuum filter, then washed one or two times, for example with distilled water, and then filtered again.

After purification of each inorganic compound, the inorganic compound can be washed and/or filtered. The inorganic compound can also be dried before packaging.

After the last cycle of sorption treatment, the material resulting from the last cycle can be subjected to a post-sorption treatment. As used herein, the term "post-sorption treatment" refers to any treatment of the material resulting from the last cycle of sorption treatment.

A post-sorption treatment may comprise a filtration and/or a washing treatment. Preferably, the material resulting from the last cycle of sorption is filtered and washed. For instance, the material can be filtered, for example with a vacuum filter, then washed one or two times, for example with distilled water, and then filtered again. After the last filtration, the obtained material can be dried and then packaged. This material resulting from the sorption treatments is neither hazardous nor valuable. It can be used as additives in building materials or for backfilling.

In a second aspect, the invention also relates to the products obtained by the method as described in the first aspect. Further aspects of the invention will be disclosed in the following applications of the method of the invention to different starting materials, which should be regarded as illustrative and not limiting the scope of this patent application. Reactions that are common in different applications are not detailed in each application.

I - Processing of coal ashes

The world has accumulated a lot of ash and slag wastes. In Russia only, 3.5 billion of tons have been accumulated. Hundreds of millions of tons are emitted as well by coal-fired power plants. This is one of the reasons for their widespread closure.

The chemical compositions of coal ashes vary greatly. In the example below (cf. Table I), the ash has a high content of Germanium (Ge). The method allows to extract any substance of interest from the coal ash.

The main interest of processing coal ashes is the chemical destruction of the aluminosilicate matrix and the extraction of amorphous forms AlzCh and SiO ₂ , that have high value on the market.

Environmentally friendly ammonium fluoride and hydrofluoride are used as a fluorine agent [NH3HF and NH3(HF) ₂ ], It should be noted that the fluorination process takes place at temperatures not exceeding 190°C, and the decomposition of the fluorine agent (starting at a temperature of 238°C) leading to the formation of hazardous hydrogen fluorides are absolutely excluded. The technical process is carried out in several stages:

1. Fluorination of aluminosilicates and other impurities. The process is described by the following exemplary chemical reactions:

AI2O3 + 6NH ₃ (HF) ₂ -> 2(NH ₄ )3AIF ₆ + 3H ₂ O

SiO ₂ + 3NH ₃ (HF) ₂ -> (NH ₄ )2SiF ₆ + 2H ₂ O + NH ₃

Fe ₂ O ₃ +6HF -> 2FeF ₂ + 3H ₂ O

GeO + NH ₃ (HF) ₂ -> GeF ₂ + H ₂ O + NH ₃

2. Ammonia released in the process of fluorination is removed to the absorption unit and is used further for the regeneration of the fluorine agent (up to 99%).

3. Dissolution of ammonium hexafluorosilicate (N H ₄ )2Si Fe with water.

4. Isolation of silicon hydroxide SiO2*mH2O by ammonia hydrolysis:

(NH ₄ )2SiFe + 4NH ₄ OH -> SiO ₂ *2H ₂ O + 6NH3HF and regeneration of the fluorine agent. 5. Calcining at + 500°C of silicon hydroxide to obtain commercial amorphous silicon dioxide.

6. Dissolution of ammonium hexafluoroaluminate (NH4)3AIFe with water.

7. Isolation of aluminum hydroxide AI(OH)s by ammonia hydrolysis (NH4)3AIFe and regeneration of the fluorine agent:

(NH ₄ )3AIF ₆ + 3NH ₄ OH -> AI(OH) ₃ + 6NH3HF

8. Calcining at 500°C of aluminum hydroxide to obtain a commercial amorphous gamma-aluminum oxide. Table I: Overview of the processing of coal ashes with the method of the invention

An ultrasonic cavitation is performed during the fluorination and HCI treatment steps. II - Purification of carbon black after pyrolysis of used tires

Carbon black is a valuable raw material that can be used as filler in rubber products and plastics. The cost of production of carbon black by pyrolysis of used tires is significantly lower than with the traditional method that relies on burning natural gas. However, carbon black obtained by the pyrolysis method contains many impurities, i.e. inorganic compounds (cf. table X), usually these inorganic elements represent from about 10% to about 15% by weight of the carbon black. Unfortunately, this high percentage of impurities, makes it impossible to use it as a raw material in the production of rubber, pigments and in high-tech products as well. Indeed, according to the requirements of international standard ASTM D1765, the carbon black must contain at least 96% of carbon and no more than about 1.2% of sulfur.

The method of the invention allows to obtain a carbon black having a carbon purity of at least about 96%, preferably of at least about 98%, more preferably of at least about 99%, even more preferably of at least about 99.5% and with a sulfur content of no more than about 1%, preferably of no more than about 0.5%, more preferably of no more than about 0.3%, and even more preferably of no more than about 0.1%. In a particular embodiment, the sulfur content is of 0% with the method of the invention. The method of the invention makes it possible to commercialize pyrolysis carbon black.

To achieve this goal, the method of the invention can be applied as following:

1) A pretreatment is first applied to the carbon black in order to degrease it and to remove the organic film that is covering the granules of carbon black. This pretreatment can be done with acetone, for example acetone with a mass ratio of about 1:3 to carbon black, at a temperature ranging from about 20°C to about 25°C. The duration of this pretreatment may be of about 24 hours.

2) Filtration, washing with distilled water and filtration.

3) A first cycle of fluorination/HCI treatment: a) Addition of a solution of a solution of ammonium fluoride NH4F with a mass ratio of CARBON BLACK:AMMONIUM FLUORIDE: WATER of about 1:1:3 and at a temperature ranging from about 80°C to about 90° C for a duration ranging from about 5 to about 7 hours. The goal of this step is to fluorinate the inorganic compounds present in the carbon black. During the treatment, the reaction medium is subjected to an ultrasonic cavitation with a specific emitter area of about 8 to about 10 m ² . b) Filtration, washing with distilled water and filtration. c) Addition to the filtrate of an aqueous solution of about 20% of hydrochloric acid with a mass ratio CARBON BLACK: HCL SOLUTION of about 1:3 and at a temperature ranging from about 20°Cto about 25°C for a duration ranging from about 20 hours to about 28 hours. The goal of this step is to convert the fluorides of inorganic compounds into soluble chlorides of inorganic compounds. During this treatment, the reaction medium is subjected to an ultrasonic cavitation as described above.

4) Filtration, washing with distilled water and filtration.

5) Additional cycles of fluorination/HCI treatments can be performed until the desire carbon purity is reached. Preferably, 1 to 5 cycles are performed, more preferably about 3 cycles are needed.

6) Filtration, washing with distilled water and filtration.

7) Drying at a temperature of about 100°C for about 2 hours.

8) Complete regeneration of all the solvent used, eliminating potential emissions into the sewage system and atmosphere. a) after acetone treatment, the solution contaminated with acetone is distillated in order to recover the acetone. The recovered acetone can be reused for another cycle of carbon black degreasing. The pyrolysis oil that has been removed by acetone from carbon black can enter the combustion chamber of the power plant. b) the gaseous NH3 and the HF produced during the cycles of fluorination/HCI treatments are collected, NH4F is regenerated, and can be reused in another cycle of fluorination treatment. c) the solution comprising the chlorides of inorganic compounds is heated at a temperature comprised between about 75°C and about 100°C, preferably at a temperature of about 100°C, in order to separate the Cl- from the inorganic compounds and to regenerate HCI. HCI can be reused in another cycle of HCI treatment.

9) The hydroxides of inorganic compounds obtained at the previous step are converted either to oxides, either to pure chemical elements. These valuable elements can then be put on the market. Table II: Overview of the processing of pyrolysis carbon black with the method of the invention III - Processing of oil shale ashes

Over 100 years of oil shale energy, a country like Estonia has accumulated over 700 million tons of oil shale ash. It pollutes rivers and water bodies.

The processing of oil shale ashes is similar as described above for coal ashes processing (cf. Application I). However, the extraction of some additional compounds of strategical importance is added, such as extraction of CaO (lime), that can be used for the decarbonization of exhaust gases (cf. Application XIII below). In nature, pure lime cannot be found, it is usually produced by calcining chalk, and a large amount of CO ₂ is emitted into the atmosphere.

The extraction of CaO is according to the following chemical reaction:

CaO + NH ₃ (HF) ₂ -> CaF ₂ + H ₂ O + NH ₃ Table III: Overview of the processing of oil shale ashes with the method of the invention IV - Processing of pyrite cinders

By now, the world has accumulated hundreds of millions of tons of pyrite cinders. Pyrite cinders are the product of burning pyrite concentrates for the production of sulfuric acid and chemical fertilizers.

Upon precipitations and other climate conditions, pyrite cinders can release a large variety of heavy metals, including highly toxic ones. On one hand, pyrite cinders pose a real threat to the environment, water and air pollution. On the other hand, they are a source of valuable compounds such as noble and rare metals.

The extraction of copper is according to the following fluorination reaction:

CuO + 2HF -> CuF2 + H2O

Sorption steps occurs as follows: The remaining material from pyrite cinders is mixed with calcium chloride and subjected to high- temperature processing. As a result, chlorides of noble metals are formed, which sublime and are captured in an absorber irrigated with an aqueous solution. In an aqueous solution, after leaving the absorber, it is sent to a container with a stirrer. The sorbent disclosed in RU 2134307, activated carbon or polyorgs is added to this container, the contents of the container are stirred at a temperature of + 80-85 ° C for 1 hour, then the treated solution is fed to the suction filter. After filtration, the resulting filtrate can be reused in the afford mentioned absorber, and the solid sorbent cake with absorbed noble metals together with the filtering material is removed from the suction filter and burned in a muffle furnace. The resulting material is a concentrate of noble metals with a concentration of at least 90% and can be sent for refining.

Table IV: Overview of the processing of pyrite cinders with the method of the invention V - Processing of phosphorite ores

There are many substandard phosphorite ores in the world. They can all be processed by the method of the invention. Phosphorites ores very often contain rare metals such as gold that can be retrieve by the method of the invention.

The main reaction of processing phosphorite ores is according to the following formula:

Ca ₃ (PO ₄ ) ₂ + 6HF = 3CaF ₂ + 2H ₃ PO ₄

Sorption description:

Phosphorite ore is subjected to fluorination according to claim 1, the resulting residue is treated with hydrochloric acid. As a result, a phosphoric acid solution is formed, in which noble metals are present. For the sorption of noble metals, our sorbent is added to this solution (polyorgs is also possible), the solution is stirred for 1 hour at a temperature of + 50-55 ° C, then the treated solution is fed to the suction filter. After filtration, the resulting filtrate is sent to the production of phosphoric acid or ammophos, and the solid sorbent cake with absorbed noble metals together with the filter material is removed from the filter end and burned in a muffle furnace. The resulting material is a concentration of noble metals with a concentration of at least 90% and can be sent for refining. If the legislation allows us to extract the gold ourselves.

Table V: Overview of the processing of phosphorites ores with the method of the invention

VI - Processing of copper concentrates

Copper concentrates is a starting material with a content of copper of about 20% to about 30%. Copper is usually extracted by metallurgical or electrolysis methods. The first one is associated with a high energy consumption and an important waste, a slag that contains copper and other expensive substances including gold, silver, molybdenum, etc. The latter generate important losses (evaporation), emission of harmful substances into the atmosphere, high energy consumption and the release of valuable products into waste. Application of the method of the invention for processing copper concentrate is a revolution in copper metallurgy.

With the method of the invention, oxides of all substances included in the copper concentrate are extracted by fluorination/HCI treatment and noble metals are extracted with sorption treatments. Copper oxide are then reduced to pure copper using graphite. With this method chemically pure copper (99.99) can be obtained. The remaining waste will be very small and harmless. Energy costs are reduced and there are no toxic emissions into the atmosphere.

The reaction of fluorination of molybdenum is according to the following reaction:

MoO3 + 6HF = MOF ₆ + 3H ₂ O

Table VI: Overview of the processing of copper concentrates with the method of the invention

VII - Extraction of hydrocarbon black from a brown coal with high ashes content

In a similar way as described in I above for the purification of carbon black obtained by pyrolysis of used tires, the inventors discovered that it is possible to obtain a material with very similar properties to carbon black by purification of a brown coal having high ashes content with the method of the invention. They called this product hydrocarbon black (or HCB).

The starting material for the production of hydrocarbon black is brown coal, preferably brown coal with an ash content of at least about 10%, more preferably of at least about 15%, even more preferably of at least about 20%. The method of the invention allows to obtain a product having a carbon purity of at least about 98%, preferably of at least about 99 %, more preferably of at least about 99.5%, even more preferably of at least about 99.7 %, alternatively of at least 99.9%. Interestingly, the HCB does not contain any sulfur. The HCB has a number of advantages over classic carbon black:

• It has a lower density than classic carbon black. Indeed, carbon black has a density of about 1.8 g/cm ³ , when the HCB of the invention has a density comprised between about 0.6 g/cm ³ and about 1.4 g/cm ³ , preferably a density of about 0.8 g/cm ³ and about 1,2 g/cm ³ , even more preferably, a density of about 1 g/cm ³ . With a density of 1 g/cm3, the tire would be 24% lighter.

• It has a higher hardness than classic carbon black.

• It does not have any sulfur. Sulfur is the main pollutant of carbon black, so it is a huge advantage.

• The raw material is the cheapest, unclaimed coal, and not natural gas or oil products.

• The cost of production is several times lower than the cost of usual carbon black.

• The manufacturing technology is much simplerthan the one usually used for production of carbon black.

• The energy consumption is several times less than with the usual method of production of carbon black.

To produce HCB, the method of the invention is applied as described in application I and II (cf. above as well as table VII below).

In laboratory conditions, the required purity was achieved with 3 cycles of the method.

Table VII: Overview of the processing of brown coal with the method of the invention

VIII - Extraction of CaO, decarbonization of exhaust gas CO2 with CaO to obtain CaCOs and purification of CaCOs and other valuable inorganic compounds

Greenhouse gas emissions is a major problem in the world nowadays. The European Union is planning to allocate 1 trillion € to find a solution to it. At the same time, when shale is burned, 1.2 kg of CO2 is released per kW of electricity produced, making the oil shale energy use inefficient.

The inventors developed a specific use of the method of the invention that allows to trap the CO2 (decarbonization) present in the plants exhaust gas.

First, the method of the invention can be used to extract CaO from a starting material according to the invention such as oil shale ashes. Oil shale ashes are an interesting starting material for that purpose as they contain about 30% of CaO. However, other starting materials containing CaO could also be used here.

Then, the extracted CaO and CO2 are submitted to several pre-treatment steps that allow to decarbonize the exhaust gases. These pre-treatment steps comprise the leaching (exhaust gases are run under water), stage-by-stage cooling, and slaked lime treatment (i.e. treatment with a mix of lime and water) of the exhaust gases, allowing the following reaction to happen: CaO +CO2 -> CaCO ₃ .

A limestone-like or chalk-like material will thus be obtained. The exhaust gases from a plant, for example a plant using the combustion of oil shale, will also contain inorganic elements, such as noble and rare earth metals, that will get trap together with the CO2 in the limestone-like material.

Then, the method of the invention can be used again to purify CaCO ₃ from the limestonelike material as well as to extract other valuable noble or rare earth metals. Table VIII: Overview of the processing of CO2 with the method of the invention Table IX: Inorganic compounds that can be extracted from different starting materials

Further aspects and advantages of this invention are disclosed in the following

5 experimental section, which should be regarded as illustrative and not limiting the scope of this application.

Examples 0

1) Purification of carbon black obtained by pyrolysis of used tires

Every year, 60 million tons of used tires are leased to special landfills in the world. After grinding, they can be used as additives in asphalt and other building materials. However, the 5 market for such additives is limited by the following factors:

1. Low price;

2. The inability to sell additives away from the place of production due to the logistical load on the price; 3. The supply is in significant excess to the demand.

As a result, the problem of recycling used tires is not solved. Worldwide, the landfills for storing used tires are full, they periodically burn (in Lithuania recently) and they constantly emit about 120 harmful substances. From an oncological point of view, the most dangerous substances are the N-nitrosamines. These gases are heavier than air and therefore do not "fly away" into the high layers of the atmosphere, but accumulate at the surface of the earth, i.e. at the level of the upper respiratory tract.

Using the method of the invention would allow to recycle these used tires in 18 million tons of carbon black per year.

At the same time, 20 million tons of carbon black are produced annually in the world from oil and gas that could be spared.

The starting material was pyrolysis carbon black manufactured by Hansa Biodiesel OU Tallinn, Estonia. The carbon black composition was analyzed (cf. Table X below). It shows a wide range of inorganic compounds for a total of 10.7% inorganic compounds. With a purity of carbon of only 89.3%, this carbon black is well below the international ASTM D1765 norm and has therefore a poor commercial value.

The method of the invention was applied to 100 g of this carbon black. First, 100 g of carbon black was put in a polyethylene reactor with a magnetic stirrer and filled with acetone, i.e. 300 g of acetone was added. The reaction was carried on for 24 hours at a temperature of 20°C, under periodic stirring. After 24 h, the reactor suspension was filtered on a laboratory vacuum filter, then washed in 2 liters of distilled water, and then filtered again in the same conditions.

The solid precipitate obtained was then placed in a fluoroplastic reactor equipped with an electric heating system. 100 grams of ammonium fluoride NH4F and 300 ml of distilled water were added to the reactor, followed by stirring and heating to 90°C. The reactor is covered with a lid with a mounted ultrasonic emitter with an active surface area of 4m ² . In the reactor cover, there is also 2 valves for supplying water and taking away ammonia (NH3). The ammonia is further dissolved in a tank of water. The fluorination treatment was under constant ultrasonic cavitation of the suspension. The fluorination was carried on for 6 hours. The amount of water added was of 40 ml. At the end of the fluorination step, the reactor suspension was filtered on a laboratory vacuum filter, then washed in 2 liters of distilled water, and then filtered again. The solid precipitate was then placed in a polyethylene reactor with a magnetic stirrer and mixed with 300 g of 20% hydrochloric acid (HCI)solution. The reactor is equipped with a cap having a valve for the removal of released hydrogen fluoride HF. The HF is then added to the tank that already contains NH3 in solution, thereby allowing to regenerate NH4F. The reaction is carried on for 24 hours at a temperature of 20°C, under periodic stirring. The reactor is covered with a lid with a mounted ultrasonic emitter with an active surface area of 4m ² . The HCI treatment was under constant ultrasonic cavitation of the suspension. At the end of this hydrochloric acid treatment step, the reactor suspension is filtered on a laboratory vacuum filter, washed 2 times in 2 liters of distilled water, and then filtered.

In total, 3 identical cycles of fluorination/HCI treatment were applied to the carbon black.

The obtained solid precipitate is dried at a temperature of 100°C for 2 hours.

The composition of the resulting carbon black was analyzed. Results are shown in Table XI (below). The resulting carbon black comprises only 0.7% of inorganic compounds. With an excellent carbon purity of 99.3%, the composition of the carbon black after treatment by the method of the invention is in accordance with the international ASTM D1765 norm. Not only the percentage of carbon is well above the requested limit (99.3% vs 96%) but the percentage of sulfur is also well below the norm (0.37% vs 1.3%).This carbon black can be used not only as a raw material in the production of rubber, and pigments but also in high-tech products.

These results demonstrate that it is possible, with the method of the invention, to produce highly pure carbon black from low-quality carbon black obtained by pyrolysis of used tires. Ultimately, the method of the invention could allow:

1. to clear the planet of used tires;

2. to save the oil and gas usually used in the production of carbon black;

3. to save the energy usually consumed for the production of carbon black;

4. to bring the tires and some other branches of the rubber industry in line with the requirements of the Rio Declaration on Environment and Development. Table X: Percentages of inorganic compounds present in a carbon black obtained by pyrolysis of used tires

Table XI: Percentage of inorganic compounds in the carbon black after treatment with the method of the invention