1 Background of the Invention

1.1 Field of the Invention

[0001] The present invention relates to methods for converting carbohydrates into hydrocarbons and heterocyclic compounds, especially oxo hydrocarbons and furans, with reduced formation of char. The methods of the invention include reacting a carbohydrate with reactant having a strong chemical affinity for carbon dioxide. The present invention has applications in the fields of organic chemistry, petroleum chemistry, and bio-chemicals.

1.2 The Related Art

[0002] Carbohydrates, also known as saccharides, are the dominant chemical constituents of the most abundant and dominant biomasses on earth, which comprise more than 60 % of the total known plant mass. Common carbohydrates include sugars, starches, cellulose and hemicelluloses, and their various chemical derivatives. Carbohydrates have the general chemical formula C _m (H ₂ 0) _n , where m and n can be equal or not, and the hydrogen and oxygen are in a ratio of 2:1 as for water (whence the name "hydrate of carbon" , since the constituents of water, hydrogen (H) and hydroxyl (OH), are bound to each carbon atom). Carbohydrates are neither chemical hydrates nor fatty acids; instead, they are polyhydroxyl-, aldehyde-, and ketone-containing compounds.

[0003] The carbohydrates are divided into four chemical families: monosaccharides, disaccharides, oligosaccharides, and polysaccharides. In general, the monosaccharides and disaccharides are commonly referred to as "sugars" . A common example of a monosaccharide is glucose; common examples of disaccharides are sucrose and lactose. Oligosaccharides are chains of fewer than ten saccharides; polysaccharides are chains longer than ten saccharides. Biologically, polysaccharides store chemical energy (e.g., starch and glycogen) and provide structural support (e.g., cellulose and hemicellulose in plants and chitin in arthropods) .

[0004] Cellulose has the chemical formula (C ₆ H ₁₀ O ₅ ) _n ; it is a polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1 — > 4)-linked D-glucose units. Cellulose is the primary structural component of the cell wall of green plants and in many forms of algae and the oomycetes. Cellulose also is both abundant and renewable: About one-third of the mass of all plant matter is cellulose (the percentage may be higher in some plants, such as 90% in cotton and 40-50% in trees). Another major carbohydrate is hemicellulose. Hemicellulose is a polysaccharide consisting of various sugars. About 20% of all plant biomass is hemicellulose. As such, hemicellulose too is both abundant and renewable.

[0005] Historically, harnessing this vast chemical resource has been done biologically, e.g., by using microbes and other organisms to convert carbohydrates into other useful chemicals. In particular, the decarbonation of carbohydrates to make alcohol is traditionally accomplished by fermentation as known in the wine making and brewing arts. New technologies have emerged over the last several decades to convert carbohydrates or general biomass into other useful chemicals, especially hydrocarbons and related compounds, including liquid biodiesel, bioethanol, and bio-oils, using fermentation; dehydration, pyrolysis (including flash pyrolysis; see Bridgewater, "Principles and practice of biomass fast pyrolysis processes for liquids" , J. Anal. Appl. Phys. 51, 3-22 (1999) and Bartek (US Patent 8,236, 173)) ; and gasification into to syngas (i.e., synthetic gas) by partial oxidation, followed by a Fischer Tropsch process to make hydrocarbons (see, e.g., Chronet, U.S. Patent No. 8,137,655) .

[0006] Hydrocarbons, so named because they formally correspond to "hydrogenated carbon" (C _m H _2n ) , and oxygen-containing derivatives ( "oxo hydrocarbons" ) , are also derived from carbohydrates by a variety of geological processes, operating over "geological" time scales, that are still not well understood. The utility of hydrocarbons, however, is well understood. Nevertheless, many scientists fear that global hydro- carbon production will soon peak, and may already peaked, thus leaving the world with the prospect of dwindling supplies of hydrocarbon fuel stocks and feedstocks for nearly all of the most important chemical building blocks.

[0007] Technology to derive hydrocarbons and oxo hydrocarbons from carbohydrates could provide an important source of useful chemical building blocks and fuels from renewable sources, especially during a time when the supply of geological hydrocarbons is increasingly uncertain. Nevertheless, despite all the advances with these traditional technologies, the production of hydrocarbons and oxygenated hydrocarbons from carbohydrate feedstocks is not efficient. Fermentation is a slow, sometimes inefficient process. Dehydration, pyrolysis, and gasification into a Fischer Tropsch process or bio-oils creates a large amount of char and other waste products (and thus wastes feedstock), and is energy intensive. As such, all of the techniques known to those having ordinary skill in the art are unacceptable for mass production.

[0008] An important advance in the effort to find efficient methods and materials to convert carbohydrates into oxo hydrocarbons is described in the above-referenced and incorporated '958 and '725 patent applications. These application describe the formation of a mixture of various oxo hydrocarbons, including alcohols, aldehydes, ketones, furans, and oxo furans from sugars such as sucrose and cellulose by heating the starting materials in the presence of a carbon dioxide-scavenging agent including magnesium oxide (MgO) and Calcium oxide (CaO). Although this work is an important advance in the search for efficient routes to convert carbohydrates into oxo hydrocarbons, it would desirable to simplify the product mixture.

[0009] Therefore, it would be advantageous to develop new methods to produce hydrocarbons and oxygenated hydrocarbons from carbohydrates, such as sugars, cellulose and hemicellulose, without creating large amounts of char or other waste products or using large amounts of energy. Due to their high abundance and renewability, using carbohydrates as a feedstock could create a "green" solution to the world's energy and chemical needs. But there are a few problems associated with trying to use carbohydrates as precursors to fuels and chemicals. The present invention meets these and other needs.

2 Summary of Embodiments of the Invention

[0010] The present invention provides methods and materials for the efficient conversion of carbohydrates into various oxo hydrocarbons and furans. In particular, the present invention provides methods for converting sucrose into acetone, acetol, furfural alcohol, and 2,5-bis(hydroxymethyl)furan.

[0011] In a first aspect, the present invention provides methods for converting carbohydrates into oxo hydrocarbons and furans. In one embodiment, the methods provided by the present invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or furan with an exothermicty of less than about 100 kcal mol ^-1 . In a more specific embodiments, the carbohydrate includes at least one saccharide, and more specifically one selected from the group consisting of mono-, di-, and tri-saccharides. Still more specific embodiments are those for which the carbohydrate is a mono- or di-saccharide. Two particular embodiments are those for which the carbohydrate is a di-saccharide, and those for which the carbohydrate is a mono-saccharide. Of the latter, yet more specific embodiments are those for which the carbohydrate is selected from the group consisting of sucrose, glucose, and fructose.

[0012] Other embodiments of the invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or furan with an exothermicty of less than about 100 kcal mol ^-1 , as described above, and further wherein the conditions effective to cause the production of at least one oxo hydrocarbon include heating the combination. In more specific embodiments, the reactants are combined at a temperature less than about 300 °C. In still more specific embodiments, the combination is heated to a temperature less than about 250 °C. In yet more specific embodiments, the combination is heated to a temperature less than about 200 °C. And in still more specific embodiments, the combination is heated to a temperature between about 150 °C and about 200 °C.

[0013] Other embodiments of the invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or furan with an exother- micty of less than about lOO kcal mol ^-1 , as described above, and further wherein the carbon dioxide-scavenging agent is selected from the group consisting of magnesium oxide, calcium formate, calcium acetate, calcium oxalate, calcium hydroxide, calcium glycolate, and l-butyl-3-methylimidazole. In a more specific embodiment, the carbon dioxide-scavenging agent is selected from the group consisting of calcium formate, calcium acetate, calcium oxalate, calcium hydroxide, calcium glycolate.

[0014] Other embodiments of the invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or furan with an exothermicty of less than about lOO kcal mol ^-1 , as described above.

[0015] In still more specific embodiments, the exothermicty is less than about 50 kcal mol more specifically less than about 25 kcal mol ^-1 , still more specifically less than about 10 kcal mol ^-1 , and still more specifically less than about 5 kcal mol ^-1 .

3 Detailed Description of Some Embodiments of the Invention

3.1 Definitions

[0016] The following terms are used herein as defined below unless specifically stated otherwise:

Oxo Hydrocarbon As used herein, "oxo hydrocarbon" and its synonym "oxygenated hydrocarbon" refer to hydrocarbon compounds containing at least one oxygen atom having double bond to a carbon atom (R(C=0)R'), such as, for example, a carbonyl, aldehyde, or carboxyl moiety. Oxo hydrocarbons can in- elude additional substituents, such as hydroxyl ( OH) .

Char As used herein, "char" refers to a charcoal-like material produced by cooking organic matter in a low-oxygen environment. Char is produced commercially by pyrolysis reactions in amounts ranging from 15%-50% of the initial feedstock. Char contains varying amounts of carbon, hydrogen, and oxygen as well as ash and other impurities that, together with the structure, determine the properties.

Carbon Dioxide-Scavenging Agent As used herein, "carbon dioxide-scavenging agent" , "scavenger" , and "C0 ₂ -scavenging Agent" refers to a material that has a high affinity to bind with, or otherwise sequesters or scavenges, C0 ₂ , and does not chemically or otherwise interfere with the conversion of carbohydrate to or- ganics, in particular oxo hydrocarbons. As described herein, examples of suitable C0 ₂ scavenging agents include: (i) a metal oxide or metal hydroxide of the alkaline, alkaline earth, or rare alkaline earth metals, which is basic with a strong chemical affinity for carbon dioxide; (ii) a nitrogen-containing-heterocyclic- containing compound, such as imidazole, pyrazole, pyrrole, pyrazine, pyridazine, pyrimidine, pyridine, and their derivatives and ionic salts; (iii) basic chemicals of NaA10 ₂ , Na ₂ Si0 ₃ ; and (iv) any combination thereof.

Furan and Furans As used herein, the terms "furan" and "furans" include both the specific heterocyclic compound furan (C ₄ H ₄ 0) derivatives thereof, either individually or in combination, unless specifically referring to the compound furan per se.

3.2 Methods for Making Oxo Hydrocarbons and Furans

[0017] The present invention provides methods and materials for the efficient conversion of carbohydrates into various oxo hydrocarbons and furans.

[0018] In a first aspect, the present invention provides methods for converting carbohydrates into oxo hydrocarbons and furans. In one embodiment, the methods provided by the present invention comprise combining a carbohydrate with a carbon dioxide- scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or at least one furan, or combination thereof, with an exothermicty of less than about lOO kcal mol ^-1 .

[0019] In a more specific embodiment, the carbohydrate includes at least one saccharide; in a more specific embodiment, the carbohydrate is selected from the group consisting of mono-, di-, and tri-saccharides. Still more specific embodiments are those for which the carbohydrate is a mono- or di-saccharide. Two particular embodiments are those for which the carbohydrate is a di-saccharide, and those for which the carbohydrate is a mono-saccharide. Of the latter, yet more specific embodiments are those for which the carbohydrate is selected from the group consisting of sucrose, glucose, and fructose.

[0020] Other embodiments of the invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or at least one furan, or combintion thereof, with an exothermicty of less than about lOO kcal mol ^-1 , as described above, and further wherein the conditions include heating the combination.

[0021] In more specific embodiments, the combination is heated to a temperature less than about 300 °C. In still more specific embodiments, the combination is heated to a temperature less than about 250 °C. In yet more specific embodiments, the combination is heated to a temperature less than about 200 °C. And in still more specific embodiments, the combination is heated to a temperature between about 150 °C and about 200 °C.

[0022] Other embodiments of the invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or at least one furan, or combination thereof, with an exothermicty of less than about lOO kcal mol ^-1 , as described above, and further wherein the carbon dioxide-scavenging agent is selected from the group consisting of magnesium oxide, calcium formate, calcium acetate, cal- cium oxalate, calcium hydroxide, calcium glycolate, and l-butyl-3-methylimidazole. In a more specific embodiment, the carbon dioxide-scavenging agent is selected from the group consisting of calcium formate, calcium acetate, calcium oxalate, calcium hydroxide, calcium glycolate, and l-butyl-3-methylimidazole.

[0023] Other embodiments of the invention comprise combining a carbohydrate with a carbon dioxide-scavenging agent, and heating the combination under conditions effective to cause the production of at least one oxo hydrocarbon or at least one furan, or combination thereof, with an exothermicty of less than about 100 kcal mol ^-1 , as described above, and further wherein the at least one oxo hydrocarbon or at least one furan, or combination thereof, is selected from the group consisting of acetone, acetol, furfuryl alcohol, 2,5-bis(hydroxymethyl)furan and combinations thereof.

[0024] In more specific embodiments of the more general embodiment just described, the at least one oxo hydrocarbon or at least one furan, or combination thereof, is a mixture of acetone, acetol, and furfuryl alcohol.

[0025] In still more specific embodiments, the exothermicty is less than about 50 kcal mol and more specifically less than about 25 kcal mol ^-1 , and still more specifically less than about 10 kcal mol ^-1 , and still more specifically less than about 5 kcal mol ^-1 .

[0026] In additional embodiments, the reaction conditions for the chemical reactions described herein are substantially non-aqueous. In still other embodiments, the reaction conditions for the chemical ractions described herein are without any significant amount of solvent. In still more specific embodiments, the reaction conditions for the chemical reactions described herein are substantially solid-state reaction conditions.

[0027] A particular embodiment of the method of the invention, described in the Examples below comprises combining a carbohydrate selected from the group consisting of sucrose, glucose, and fructose with a carbon dioxide-scavenging agent selected from the group consisting of magnesium oxide, calcium formate, calcium acetate, calcium oxalate, calcium hydroxide, calcium glycolate, and l-butyl-3-methylimidazole, and heating the combination at a temperature of between about 130 °C and about 220 °C. In a more specific embodiment, the carbon dioxide-scavenging agent is selected from the group consisting of calcium formate, calcium acetate, calcium oxalate, calcium hydroxide, calcium glycolate, and l-butyl-3-methylimidazole, and the combination with the carbohydrate listed above is heated at a temperature of between about 130 °C and about 220 °C.

[0028] The methods and materials used in the invention will be familiar to those having ordinary skill in the art. Generally, a starting material suitable for making a C0 ₂ scavenging material is made. Typical starting materials include calcium oxide (CaO) and limestone powder, which can be purchased from commercial sources as indicated below. In the case of CaO, the starting material is mixed with water to first make calcium hydroxide (Ca(OH) ₂ ), which is then rigorously dried. In the case of limestone powder, the powder is first calcined and then mixed with water. Still other materials and methods for making suitable scavengers will be apparent to those having ordinary skill in the art. Examples of other suitable scavengers include magnesium oxide, calcium formate, calcium acetate, calcium oxalate, calcium hydroxide, calcium glycolate, and l-butyl-3-methylimidazole. The scavenger can be used individually or in combniation. The preparation of these materials to make suitable scavengers will be understood by those having ordinary skill in the art.

[0029] The reactants are heated at a temperature less than about 300 °C, more particularly less than about 250 °C, and still more particularly less than about 200 °C. Still more specific embodiments are those in which the reactants are heated at a temperature between about 130 °C and about 300 °C, more particularly, between about 150 °C and about 250 °C, still more particularly between about 150 °C and about 220 °C, and yet still more particularly between about 150 °C and about 200 °C.

[0030] The heating of the reactants is heating of reactants can be achieved in various ways that will be familiar to those having ordinary skill in the art. By way of example and not limitation, heating can be direct or indirect means. Non-limiting examples of direct heating include using a pre-heated carrier gas such as N ₂ or product components such as acetone vapor, or a combination thereof, passing through the reactants. Non- limiting examples of indirect heating include contact heating by placing reactants in contact with a surface of retaining walls heated by a heat source such as resistance electric heating, high pressure steam, a preheated media such as oils, or by radiation (solar, artificial lighting, etc.) The heating can also be provided by microwave, direct radiations, dielectric at high frequency electric field. The determination of heating rates will be familiar to those having ordinary skill in the art.

3.3 Examples

3.3.1 Example 1: Sucrose With Scavenger Made From Calcium Oxide

3.3.1.1 Step 1: Preparation of Scavenger

[0031] 19.66 g of CaO powder, chemical reagent grade, purchased from Sigma- Aldrich was placed in a 100 mL A1 ₂ 0 ₃ crucible, and 16.11 g of deionized ( "D.I." ) water was added to to the crucible.

[0032] After the hot steam subsided, the crucible was placed in a tubular furnace (Carbolite, six-inch diameter) and was heated to 360 °C while held for 30 min. The sample was then cooled down to room temperature in a desiccator.

3.3.1.2 Step 2: preparation of carbohydrate di-saccharide sucrose:

[0033] 20 g of Domino Granulated sugar, a cane sugar from Domino Foods, was ground in pestle and mortar to fine powder. Alternatively and interchangeably beet sugar was used.

3.3.1.3 Step 3: Preparation of the Scavenger and Sucrose:

[0034] In a 250 mL plastic bottle jar, 23.030 g of powdered C0 ₂ scavenger and 16.301 g of sugar powder were added along with an adequate amount of the milling media (Zr ₂ 0 balls). The jar with the mixture and the milling media was placed on a roller mill and milled for 3 d at a pre-set speed. This stock thus prepared was ready for uses. 3.3.1.4 Step 4: Liquid-Phase Solid-State Reactor

[0035] A modified tubular furnace (Carbolite, 6-inch in diameter) was used as the heating mantel. It was set up horizontally and electrically heated.

[0036] A 100 niL round bottom modified Schlenk reactor from LaBoy was used as the liquid-phase solid-state reactor.

[0037] An air cooled condenser with a sample receiver was used for collecting condensates.

[0038] The reactor system was set up to allow little or no reflux or no condensate flowing back into the reactor during the reaction.

[0039] A second thermal couple ( "TC" ) was inserted inside the reactant mixture to monitor the reaction temperature during the reaction.

3.3.1.5 Step 5: Reaction and the Products

[0040] 32.319 g of the reactant mixture which contained 18.929 g of C0 ₂ scavenger and 13.39 g of sucrose was charged into the reactor. The heating mantel, the condenser, the collector, and the reaction temperature monitor were then installed in a hood.

[0041] The heating mantel was set to 250 °C at the maximum heating rate possible. The reaction temperature was monitored by a second thermal couple inserted inside of the reactant mixture. Substantial difference in temperature readings between the heating mantel and the monitor was observed. It only took 9 min for the heating mantel to reach the pre-set temperature of 250 °C, while at the same time the reactant mixture (second TC) was merely at 68.4 °C. When the temperature inside the reactant mixture reached 155.3 °C, a colorless condensate was formed.

[0042] As the reactant temperature was further increased to 209 °C, more condensate was collected. Its color had changed to a faint greenish and then to slight yellow tint. The heating mantel was then manually and incrementally set to 300 °C, 320 °C, 340 °C, and 360 °C at the maximum heating rate. Once the reactant temperature reached 300 °C, the reaction was manually stopped. [0043] The total amount of volatile and condensate formed during the reaction was weighed to be 5.04 g per 13.39 g sucrose charged, giving a yield of 37.0 % based on sugar charged.

[0044] Only three primary organic components of furfuryl alcohol, acetol and acetone were identified by GC/MASS in the condensates, and their molar ratio was found to be near 1: 1: 1 by a separate GC analysis.

3.3.2 Example 2: Sucrose, Scavenger Made From Lime Stone Powder 3.3.2.1 Step 1: preparation of Scavenger:

[0045] Lime stone powder was purchased from online kelp41ess.com which contained 98% calcium carbonate. The powder was a low cost grade lime with green hue and its main use was for balancing pH and supplementing calcium for soil. 1000 g of the powder was added to a ceramic crucible (A1 ₂ 0 ₃ ) which was further placed in a box furnace (Vulcan model 3-550) for calcination. Alternatively a Carbolite tube furnace with six-inch diameter was used for calcination of samples less than 300 g.

[0046] The lime powder was heated to 1050 °C and held for two hours. The calcined sample was cooled down to ambient temperature inside the box furnace with its door closed. Alternatively for samples less than 300 g they were transferred to and cooled down in a desiccator.

[0047] For 1000 g of lime stone powder, after calcination, 595 g of the calcined powder was obtained.

[0048] 500 g of the calcined powder in a 2000 mL Pyrex beaker, was added with 317 g of tap water. After the hot steam subsided, the beaker was placed in a box furnace (Vulcan Model 3-550) and heated to 360 °C for 4 h. The sample was cooled down to room temperature in the furnace with the door closed. About 660 g of the sample was obtained and it was ready for later use as the C0 ₂ scavenger. 3.3.2.2 Step 2: Preparation of Carbohydrate Di-Saccharide Sucrose:

[0049] 500 g of Domino Granulated sugar, a cane sugar from Domino Foods, was ground in pestle and mortar to fine powder. Alternatively and interchangeably beets sugar was used.

3.3.2.3 Step 3: Preparation of the Scavenger and Sucrose

[0050] In a 250 mL plastic bottle jar, 111 g of powdered C0 ₂ scavenger and lOO g of sugar powder were added along with an adequate amount of the milling media (Zr ₂ 0 balls). The jar with the samples and the milling media was placed on a roller mill and milled for 3 d at pre-set speeds.

[0051] More mixtures were prepared by repeating the same procedure.

3.3.2.4 Step 4: Liquid-Phase Solid-State Reactor System

[0052] A customer made heating mantel with an inside dimension of 7.5 inch x 7.5 inch x 7.5 inch, equipped with electrical heating capable of heating rates from 2 °C to 200 °C per hour, was used for providing the heating.

[0053] A 2 L, one-neck Pyrex flask was used as the liquid-phase solid-state reactor.

[0054] A water cooled condenser with a three-way cow-type receiver was used for collecting condensates.

[0055] Nitrogen gas (99.99 %) was installed to flush or to purge the reactor before, during and after reaction.

[0056] The reactor and product collection was set up to allow little or no reflux or no condensate flowing back into the reactor during the reaction.

[0057] A second thermal couple was inserted inside the reactant mixture to monitor the reaction temperature.

3.3.2.5 Step 5: Reaction and the Products

[0058] 697.6 g of the reactant mixture which contained 367g of C0 ₂ scavenger and 330.6 g of sucrose was charged into the reactor. The heating mantel, the condenser, the collector, the nitrogen gas line, and the reaction temperature monitor were then installed in a hood.

[0059] Nitrogen gas at a flow rate of 200 rriL min ^-1 was used to flush the reactor for 30 min before the heating, then reduced to 100 rriL min ^-1 during heating and further reduced to lO mL min ^-1 during the peak of the reaction.

[0060] The reactor was heated at a preset rate of 40 °C per hour till 230 °C. The reaction temperature was monitored by a second thermal couple inserted about 2 cm beneath the surface of the reactant mixture. Substantial difference of temperature readings between the heating mantel and the monitor was observed. When the heating mantel temperature reached 202 °C, the second TC monitor inside the reactant mixture only read 151.9 °C— at which noticeable condensates were formed with faint greenish tint.

[0061] When the heating mantel reached the preset temperature of 230 °C, the heating was manually stopped at this moment the second monitor TC read the reactant temperature at 159.5 °C. It was the start of peaking of reaction that a heavy flow of condensates was collected. Within 10 min, the flow of condensate was ceased while the reactor temperature continued to rise. The reaction was completed promptly.

[0062] The total amount of volatiles and condensates formed during the reaction was weighed to be 131.6 g per 330.6 g sucrose charged, giving a yield of 39.7 % based on sugar charged.

[0063] Only three primary organic components of furfuryl alcohol, acetol and acetone were identified by GC/MASS in the condensates, and their molar ratio was found to be near 1: 1: 1 by a separate GC analysis when compensated for the expected losses.

3.3.3 Example 3: Sugar cane, Scavenger Made From Lime Stone Powder and a 20-cm Long Tubular Reactor

3.3.3.1 Step 1: Preparation of Scavenger:

[0064] Lime stone powder was purchased from online kelp41ess.com which contained 98% calcium carbonate. The powder was a low cost grade lime with green hue and its main use was for balancing pH and supplementing calcium for soil. 1000 g of the powder was added to a ceramic crucible (A1 ₂ 0 ₃ ) which was further placed in a box furnace (Vulcan model 3-550) for calcination. Alternatively a Carbolite tube furnace with 6-inch diameter was used for calcination of samples less than 300 g.

[0065] The lime powder was heated to 1050 °C and held for two hours. The calcined sample was cooled down to ambient temperature inside the box furnace with its door closed. Alternatively for samples less than 300 g they were transferred to and cooled down in a desiccator.

[0066] For 1000 g of lime stone powder, after calcination, 595 g of the calcined powder was obtained.

[0067] 500 g of the calcined powder in a 2000 mL Pyrex beaker, was added with 317 g of tap water. After the hot steam subsided, the beaker was placed in a box furnace (Vulcan Model 3-550) and heated to 360 °C for 4 h. The sample was cooled down to room temperature in the furnace with the door closed. About 660 g of the sample was obtained and it was ready for later use as the C0 ₂ scavenger.

3.3.3.2 Step 2: Preparation of Sugar Cane Dust:

[0068] Two kilograms of raw sugar cane purchased in an unspecified Downtown Boston Supermarket, was stored and naturally de-hydrated in a dark and slightly ventilated storage cabinet for one year. The dried feedstock had substantially shrunk in size. It had visibly been covered by many mold spots on its skin and the inner cane had also turned to black and brown.

[0069] The aged cane as it is was mechanically cut into pieces less than 1 cm long and was further crushed into fine dust (like saw dust) in a 16-speed kitchen food blender made by Oster at the highest setting.

[0070] The sugar cane dust was then measured for its water content, its sugar content, and its bagasse (fiber) content and they were estimated to be 14.8 wt.-%, 29.7 wt.- %, and 55.5 wt.-% respectively. The water content was estimated by its weight loss after drying the cane dust at 150 °C for 24 h till no measurable weight changes. The sugar content was estimated by its weight loss after repeated de-ionized water washings, vacuum nitrations and subsequent dryings at 150 °C till no measurable weight changes.

3.3.3.3 Step 3: Preparation of the Reactant Mixture and Sugar Cane Dust

[0071] Equal weight of C0 ₂ scavenger powder and cane dust was prepared by mechanical mixing and grinding in pestle and mortar. A stock of the reactant mixture thus made consisted of 20.47g of C0 ₂ scavenger and 20.76 g of the cane dust.

3.3.3.4 Step 4: Horizontally Oriented Liquid-Phase Solid-State Reactor System

[0072] A Carbolite tube furnace as the heating mantel was set horizontally. A 20 cm- long tubular Pyrex reactor was inserted half way into the hot zone of the furnace with the opening end tilted downward preventing condensates from flowing back into the hot zone of the reactor during reaction. An air cooled elbow and a 5-ml collection flask was used to collect the liquid product. No nitrogen blank gas was used.

3.3.3.5 Step 5: Reaction and the Products

[0073] 4.076 g of the reactant mixture which contained 2.024 g of C0 ₂ scavenger and 2.052 g of the sugar cane dust was charged into and at the closed end of the tubular reactor. The reactor was then inserted half way into the hot zone of the heating mantel. The reactor was installed in a vented area.

[0074] The reactor was first heated at the fastest possible heating rate till 150 °C (less than 5 min from the start). It was then manually and incrementally raised by 10 °C at every 5 min to 300 °C. At 160 °C colorless condensate was formed on the cold side of walls of the reactor and the elbow. At 210 °C to 220 °C the liquid collected appeared to show a faint greenish tint, and soon after a pleasant and sweet aroma resembling food processing such as cooking of Jasmin rice appeared. The heating was manually stopped when it reached 290 °C and the reactor was immediately cooled down.

[0075] The charged reactant mixture contained 2.052 g of the cane dust that was estimated to be 0.303 g of water, 0.609 g of sugar and 1.139 g of bagasse (fiber). The total amount of volatile formed during reaction plus water from the cane dust (about 0.303 g) was measured at 0.701 g. Minus water from the cane dust, it derived the reaction products weighing 0.398 g (0.701— 0.303 = 0.398), giving a yield of 57.7 wt.-% based on the sugar charged.

[0076] Only three primary organic components of furfuryl alcohol, acetol and acetone were identified in the condensates, and their molar ratio was found to be near 1: 1:1 by a GC analysis.

3.3.4 Example 4— Fructose, Scavenger Made From Lime Stone Powder 3.3.4.1 Step 1: Preparation of Scavenger

[0077] Lime stone powder was purchased from online kelp41ess.com which contained 98 % calcium carbonate. The powder was a low cost grade lime with green hue and its main use was for balancing pH and supplementing calcium for soil. 1000 g of the powder was added to a ceramic crucible (A1 ₂ 0 ₃ ) which was further placed in a box furnace (Vulcan model 3-550) for calcination. Alternatively a Carbolite tube furnace with 6 inch diameter was used for calcination of samples less than 300 grams.

[0078] The lime powder was heated to 1050 °C and held for two hours. The calcined sample was cooled down to ambient temperature inside the box furnace with its door closed. Alternatively for samples less than 300 g they were transferred to and cooled down in a desiccator. For 1000 g of lime stone powder, after calcination, 595 g of the calcined powder was obtained.

[0079] 500 g of the calcined powder in a 2000 mL Pyrex beaker, was added with 317 g of tap water. After the hot steam subsided, the beaker was placed in a box furnace (Vulcan Model 3-550) and heated to 360 °C for 4 h. The sample was cooled down to room temperature in the furnace with the door closed. About 660 g of the sample was obtained and it was ready for later use as the C0 ₂ scavenger.

3.3.4.2 Step 2: Preparation of Carbohydrate Mono-Saccharide Fructose

[0080] 10 g of Fructose, a food grade purchased from Denver Spice, was ground in pestle and mortar to fine powder.

3.3.4.3 Step 3: Preparation of the Reactant Mixture and Fructose:

[0081] 1.629 g of powdered C0 ₂ scavenger and 1.067g of fructose powder were milled and mixed in pestle and mortar.

3.3.4.4 Step 4: Liquid-Phase Solid-State Reactor

[0082] A tubular furnace (Carbolite one-inch in diameter) was used as the heating mantel and it was placed horizontally.

[0083] A 10 rriL tubular reactor from Ace was used as the liquid-phase solid-state reactor.

[0084] An elbow and a 5 mL flask were used for collecting condensates.

[0085] The reactor and the collector were set up horizontally to allow little or no reflux or no condensate flowing back into the reactor during the reaction.

3.3.4.5 Step 5: Reaction and the Products

[0086] 2.521 g of the reactant mixture which contained 1.523 g of C0 ₂ scavenger and 0.998 g of fructose was charged into the reactor. The heating mantel, the elbow and the 5 rriL flask were then installed in a hood.

[0087] The heating mantel was set to 250 °C at a heating rate of 3.33 °C min ^-1 . Condensate on the walls of the elbow and the collector flask was observed when the temperature reached 135 °C and the reaction was stopped when it reached 250 °C. [0088] The total amount of volatiles and condensates formed during the reaction was weighed to be 0.498 gram per 0.998 g fructose charged, giving a yield of 49.9 weight-% of based on sugar charged.

[0089] The colorless liquid solidified at— 10 °C and only three primary organic components of furfuryl alcohol, acetol and acetone were identified, and their molar ratio was found to be near 1: 1:3 by a GC analysis.

3.3.5 Example 5— Glucose and Scavenger Made From Lime Stone Powder 3.3.5.1 Step 1: Preparation of Scavenger

[0090] Lime stone powder was purchased from online kelp41ess.com which contained 98 % calcium carbonate. The powder was a low cost grade lime with green hue and its main use was for balancing pH and supplementing calcium for soil. 1000 g of the powder was added to a ceramic crucible (A1 ₂ 0 ₃ ) which was further placed in a box furnace (Vulcan model 3-550) for calcination. Alternatively a Carbolite tube furnace with 6 inch diameter was used for calcination of samples less than 300 g.

[0091] The lime powder was heated to 1050 °C and held for two hours. The calcined sample was cooled down to ambient temperature inside the box furnace with its door closed. Alternatively for samples less than 300 g they were transferred to and cooled down in a desiccator.

[0092] For 1000 g of lime stone powder, after calcination, 595 g of the calcined powder was obtained.

[0093] 500 g of the calcined powder in a 2000 mL Pyrex beaker, was added with 317 g of tap water. After the hot steam subsided, the beaker was placed in a box furnace (Vulcan Model 3-550) and heated to 360 °C for 4 h. The sample was cooled down to room temperature in the furnace with the door closed. About 660 g of the sample was obtained and it was ready for later use as the C0 ₂ scavenger. 3.3.5.2 Step 2: Preparation of Carbohydrate Mono-Saccharide Glucose

[0094] 10 g of glucose, food grade purchased on Amazon.com, was ground in pestle and mortar to fine powder.

3.3.5.3 Step 3: Preparation of the Reactant Scavenger and Glucose

[0095] 1.449 g of powdered C0 ₂ scavenger and 1.299 g of glucose powder were milled and mixed in pestle and mortar.

3.3.5.4 Step 4: Liquid-Phase Solid-State Reactor

[0096] A tubular furnace (Carbolite one- inch in diameter) was used as the heating mantel and it was placed horizontally.

[0097] A 10 rriL tubular reactor from Ace was used as the liquid-phase solid-state reactor.

[0098] An elbow and a 5 mL flask were used for collecting condensates.

[0099] The reactor and the collector were set up horizontally to allow little or no reflux or no condensate flowing back into the reactor during the reaction.

3.3.5.5 Step 5: Reaction and the Products

[0100] 2.332 g of the reactant mixture which contained 1.230 g of C0 ₂ scavenger and 1.102 g of glucose was charged into the reactor. The heating mantel, the elbow and the 5 rriL flask were then installed in a hood.

[0101] The heating mantel was set to 250 °C at a heating rate of 3.33 °C min ^_1 . Condensate on the walls of the elbow and the collector flask was observed when the temperature reached 135 °C and the reaction was manually stopped when it reached 250 °C.

[0102] The total amount of volatiles and condensates formed during the reaction was weighed to be 0.392 g per 1.102 g glucose charged, giving a yield of 35.6 wt.-% based on sugar charged. [0103] Only three primary organic components of furfuryl alcohol, acetol and acetone were identified in the colorless liquid, and their molar ratio was found to be near 0.5:2:3 by a GC analysis.

4 Conclusion

[0104] The above description of the embodiments, alternative embodiments, and specific examples, are given by way of illustration and should not be viewed as limiting. Further, many changes and modifications within the scope of the present embodiments may be made without departing from the spirit thereof, and the present invention includes such changes and modifications.

[0105] It will be apparent to those of ordinary skill in the art that the present invention provides an important advance in the production of hydrocarbons from plants, more particularly, the production of important oxo hydrocarbons and furans from carbohydrates. The materials and methods described herein can be further extended by the use of different scavengers, starting materials, and reaction conditions without departing from the scope and spirit of the present disclosure and claims.