PRODUCING A HYDROCARBON COMPOSITION

FIELD OF THE INVENTION

The present disclosure relates to a hydrocarbon composition and to a method for producing a hydrocarbon composition.

BACKGROUND

Isomerization refers to a chemical process by which a compound is transformed into one or more of its isomeric forms, i.e. forms having the same chemical composition but a different structure or configuration and possibly dif- ferent physical and chemical properties. For example, branched-chain hydrocarbons are better motor fuels than their straight-chain isomers. The isomerization of straight-chain hydrocarbons to their corresponding branched-chain isomers represents an example of isomerization reactions of great industrial importance.

Isomerized hydrocarbon compositions with a lowered aromatic content are commercially available in a chain length of C7-C14. The dearomatization method used for obtaining these highly isomerized hydrocarbon compositions is hydrogenation. In these compositions the aromatic content is 1 ppm.

A method for obtaining isomerized hydrocarbon fractions is disclosed in a patent application WO2015/101837, including a chain length of C14-C15. SUMMARY

An object is to provide a hydrocarbon composition with extremely low aromatics content. The objects are achieved by a method, composition, and use thereof, which are characterized by what is stated in the independent claims. Preferred embodiments of the invention are disclosed in the dependent claims.

An exemplary method is based on conducting hydrodeoxygenation and optionally isomerization of raw material, wherein the method further comprises one or more solvent extraction steps and optionally hydrogenation to remove aromatic and/or naphthenic hydrocarbons from the material. The original aromatic and/or naphthenic content of the raw material is less than 2 vol-%. In the method, the aromatic and/or naphthenic content is reduced by more than 45%, preferably by more than 60%. An exemplary composition contains hydrocarbons produced by said method, wherein the total aromatic and/or naphthenic hydrocarbon content of the composition is less than a predefined low value, and C15-C20 i-paraffins are the main fraction of the hydrocarbon content of the composition, weight basis. DETAILED DESCRIPTION OF EMBODIMENTS

The following embodiments are exemplary. Although the specification may refer to "an", "one", or "some" embodiment(s) in several locations, this does not necessarily mean that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. Furthermore, words "comprising", "containing" and "including" should be understood as not limiting the described embodiments to consist of only those features that have been mentioned and such embodiments may contain also features/structures that have not been specifically mentioned.

An embodiment discloses a method for dearomatization and/or denaphthenization of raw material to produce a hydrocarbon product. The method is based on the use of hydrodeoxygenation and solvent extraction, and optionally isomerization and hydrogenation, in combination. This means that the method comprises the consecutive method steps of hydrodeoxygenation and solvent extraction, and possibly isomerization and hydrogenation. The method may further comprise a step of separating different hydrocarbon fractions by fractionation. The method steps may be carried out in one or multiple reactors.

The order of said method steps may differ from the one given above. For example, 1 ^st step may be solvent extraction, 2 ^nd step may be hydrogenation, and 3 ^rd step may be solvent extraction, or 1 ^st step may be hydrogenation, and 2 ^nd step may be solvent extraction.

In an embodiment, one or more of said method steps may be performed simultaneously.

A highly isomerized hydrocarbon product with very low aromatic (or naphthenic) content may be produced with a process combining hydrodeoxygenation, isomerization and solvent extraction (and optionally hydrogenation and/or fractionation).

The method may be carried out in one or multiple reactors.

The feedstock/raw material for the process may be paraffinic hydrocarbon, isoparaffinic hydrocarbon, natural gas, biogas, coal, diesel and/or naphtha or it may be of renewable and/or biological origin, such as vegetable oil, hydrotreated vegetable oil, animal fat, fish fat, microbial oil, algae oil and/or any other suitable natural or biological oil, such as natural waste oil or natural residue oil. Solvent extraction provides an effective and inexpensive method for ar- omatics and/or naphthenics removal. The method enables further removal of aro- matics and/or naphthenics from a raw material having a low aromatics and/or naphthenics content.

Paraffins arranged in straight chains may be referred to as normal paraffins i.e. n-paraffins, and paraffins arranged in branched chains may be referred to as isoparaffins i.e i-paraffins. A composition produced by the method may contain n- and i-paraffins in different ratios depending on the processing parameters.

An embodiment discloses a hydrocarbon composition A and a method for producing the hydrocarbon composition A. The hydrocarbon composition A contains mainly C5-C10 i- and/or n-paraffins. In the method for producing the hydrocarbon composition A, the steps of hydrodeoxygenation, isomerization and solvent extraction are combined with a fractionation step where i- and n-paraffins are separated. The end product obtained contains over 90 wt-% C5-C10 i- and/or n- paraffins.

Another embodiment discloses a hydrocarbon composition B and a method for producing the hydrocarbon composition B. The hydrocarbon composition B contains over 80 wt-% C10-C20 i-paraffins and less than 20 wt-% n-paraffins. In the method for producing the hydrocarbon composition B, the steps of hy- drodeoxygenation, isomerization and solvent extraction may be combined with a fractionation step. End products with a variable content of C14-C20 paraffins (over 80 wt-% of i-paraffins) are obtained. The fractionated end products may be, for example, mainly C10-C15 paraffins, mainly C14-C16 paraffins, mainly C15-C18 paraffins and/or mainly C17-C18 paraffins.

In an embodiment, a composition is disclosed containing highly isomer- ized hydrocarbons, wherein the total aromatic and/or naphthenic hydrocarbon content of the composition is less than a predefined low value, and i-paraffins are the main fraction of the hydrocarbon content of the composition.

In an embodiment, the total aromatic and/or naphthenic hydrocarbon content of the composition is less than 10 000 ppm, preferably 4000 ppm or less, more preferably 2000 ppm or less, yet more preferably 1600 ppm or less, yet more preferably 1200 ppm or less, yet more preferably 1000 ppm or less, yet more preferably 500 ppm or less, yet more preferably 100 ppm or less, yet more preferably 50 ppm or less, yet more preferably 30 ppm or less, most preferably about 20 ppm, volume basis. In an embodiment, the hydrocarbon composition is produced from renewable and/or biological raw material. The renewable and/or biological raw material comprises at least one of vegetable oil, animal fat, fish fat, microbial oil, algae oil, natural waste oil, and or natural residue oil.

The hydrocarbons may be C15-C20 hydrocarbons or C5-C10 hydrocarbons.

In an embodiment, the composition comprises 80 wt-% C10-C20 i-par- affins or more, preferably about 93 wt-%, based on the total weight of the composition, and 20 wt-% C10-C20 n-paraffins or less, based on the total weight of the composition. C14-C20 paraffins, C10-C15 paraffins, C14-C16 paraffins, C15-C18 paraffins or C17-C18 paraffins are the main fraction of the hydrocarbon content of the composition. The total i-paraffinic content of the composition is more than 80 wt-%, based on the total weight of the composition. The total n-paraffinic content of the composition is less than 20 wt-%, based on the total weight of the composi- tion.

In an embodiment, the composition comprises about 90 wt-% C5-C10 i- and/or n-paraffins, based on the total weight of the composition.

In an embodiment, the hydrocarbon composition is produced by a process comprising hydrodeoxygenation and optionally isomerization of raw material, comprising at least one step of solvent extraction, and optional steps of hydrogena- tion and/or fractionation. The original aromatic/naphthenic content of the raw material/feedstock is less than 2 vol-%. In the method, the original aromatic/naphthenic content is reduced by more than 45%, preferably by more than 60%.

In an embodiment, the composition is suitable for use as a solvent or a solvent component.

In an embodiment, the composition is in liquid form.

In an embodiment, the composition is an emulsion.

In an embodiment, the composition may be used in a coating, paint, lacquer, varnish, polish, ink, adhesive, sealant, resin, plastic, catalyst, cleaning compo- sition, peroxide desensitizer, pigment dispersion, carrier fluid for an active ingredient, antioxidant, biocide, insecticide, air freshener, crop protection composition, detergent, grease removal composition, dry cleaning composition, cosmetic, personal care composition, pharmaceutical, extender in a dental impression material, vaccine, food ingredient, flavour composition, fragrance, natural oil extraction, oil field chemical, drilling mud composition, extraction process composition, plasti- cizer for elastomer, paper processing chemical, lubricant, functional fluid, transformer oil, metal working composition, rolling or cutting fluid, water treatment composition, wood treatment composition, construction chemical, mould release material, explosive, mining chemical, solvent extraction composition, fuel compo- nent, heating oil, lamp oil, or a combination thereof.

In an embodiment, the method for producing the hydrocarbon composition comprises conducting hydrodeoxygenation and optionally isomerization of raw material, wherein the method further comprises a step of solvent extraction and optionally hydrogenation. The method may further comprise conducting sep- aration of the resulting material, wherein the separation may include fractionation or any other suitable separation method. The method may be carried out in one or multiple reactors.

In an embodiment, the solvent used in the solvent extraction includes at least one of N-methyl-2-pyrrolidone (NMP), furfural, dimethyl formamide (DMF), DMSO (dimethylsulphoxide), DMI (dimethyl isosorbide), polar solvent, aromatic solvent, dipolar aprotic solvent, ionic liquid, deep eutectic solvent, sulpholane, glycol, and phenol.

A composition comprising highly isomerized hydrocarbons as used herein refers to a composition where the degree of isomerization is high. For ex- ample, the composition may comprise a high weight percentage of i-paraffins compared to the weight percentage of normal paraffins (n-paraffins), so that the main fraction of the composition comprises i-paraffins. However, it is also possible that the composition comprises an equal or higher weight percentage of n-paraffins compared to the weight percentage of i-paraffins. It is also possible that the com- position comprises a high weight percentage of i-paraffins but no n-paraffins, or vice versa.

According to an exemplary aspect, provided is a method for producing the composition comprising said paraffins. The method can comprise hydrotreat- ing a raw material of renewable/biological origin to obtain a hydrotreated product comprising n-paraffins and isomerizing the hydrotreated product to obtain an isomerized product comprising i-paraffins and separation of said composition by solvent extraction and possibly fractionation.

Example 1

A trace amount of aromatics from the composition B containing approx- imately 90 wt-% i-paraffins and 0,31 vol-% aromatic compounds were extracted with two different solvents, according to a 4-step-working procedure. The chosen solvents were N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF). 10 vol-% distilled water was added in both solvents to increase the efficiency. 100 ml of the composition B was extracted three times with the solvent in a 1:1 composition B to solvent ratio. A mixing time of 2 min was used in each step. A 500 mL glass separation funnel was used. After mixing, the extract was centrifuged to separate the extract. Table 1 illustrates the aromatic contents (in vol-%) of samples extracted in 3-step solvent extraction followed by a washing step with water as analyzed by using a NM77 method (UV spectrophotometric detection method). NMP= N-methyl-2-pyrrolidone, DMF=dimethylformamide.

Table 1

As can be seen from Table 1, both the tested solvents clearly reduced the amount of aromatic residues in the composition B. Already a single step solvent extraction procedure reduced the amount of aromatics in the composition B by 35% in case of NMP, and by 48% in case of DMF. After three solvent extraction steps, NMP showed to be more effective leading to a 61% reduction in the aromatic content of the composition B.

Thus, liquid-liquid extraction (solvent extraction) may be applied for the separation of aromatics and/or naphthenics from the compositions A and/or B. Solvents suitable for the extraction of the aromatic/naphthenic compounds from the compositions A and/or B may include, for example, N-methyl-2-pyrrolidone (NMP), furfural, dimethyl formamide (DMF), DMSO (dimethylsulphoxide), DMI (dimethyl isosorbide), and/or phenol. Water or some other co-solvent, such as alco- hoi, may be used to enhance the separation process of the aromatics from the composition. Also certain ionic liquids and/or deep eutectic solvents, such as choline chloride, may be used to remove aromatics from the composition.

In an embodiment, the method comprises performing the consecutive (and/or simultaneous) steps of hydrodeoxygenation, and optionally isomerization and hydrogenation, and one or more solvent extraction steps until the aromatics and/or naphthenics content of the material is reduced by more than 45%; for example, several consecutive solvent extraction steps may be required until the desired reduction of 45% in the aromatics and/or naphthenics content of the material is achieved and hydrocarbons are produced with an aromatics and/or naphthenics content of less than 10 000 ppm, preferably 4000 ppm or less, more preferably 2000 ppm or less, yet more preferably 1600 ppm or less, yet more preferably 1200 ppm or less, yet more preferably 1000 ppm or less, yet more preferably 500 ppm or less, yet more preferably 100 ppm or less, yet more preferably 50 ppm or less, yet more prefer-ably 30 ppm or less, most preferably about 20 ppm, volume basis

It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.