Method and apparatus for treatment of biomass substrates

Abstract

A system and method for the treatment of biomass comprising mixing a biomass with an ionic liquid (IL) to swell the biomass and electromagnetic (EM) heating, preferably radiofrequency (RF) heating, said biomass. Additionally, a method of acidolysis of biomass comprising mixing biomass in an ionic liquid (IL) to swell the biomass; adding an acid, to lower the pH of the biomass below pH 7; applying radio frequency (RF) heating to the biomass to heat to a target temperature range; applying ultrasonic heating, electromagnetic (EM) heating, convective heating, conductive heating, or combinations thereof, to the biomass to maintain the biomass at a target temperature range; washing the treated biomass; and recovering sugars and released lignin.

We claim: 
     
         1 . A method for the treatment of biomass comprising mixing a biomass with an ionic liquid (IL) to swell said biomass and electromagnetic (EM) heating, preferably radiofrequency (RF) heating, said swelled biomass. 
     
     
         2 . The method of  claim 1 , wherein said biomass is agricultural residues, optionally corn stover, wheat straw, bagasse, rice hulls, or rice straw; wood and forest residues, optionally pine, poplar, douglas fir, oak, saw dust, paper/pulp waste, or wood fiber; algae; kudzu; coal; cellulose, lignin, herbaceous energy crops, optionally switchgrass, reed canary grass, or miscanthus; lingocellulosic biomass, optionally comprising lignin, cellulose, and hemicellulose; plant biomass; or mixtures thereof. 
     
     
         3 . The method of  claim 1 , wherein heating comprises at least two phases, a first phase comprising application of electromagnetic (EM) heating, optionally a variable frequency in the electromagnetic spectrum, variable frequency heating, radiofrequency (RF) heating, or a combination thereof, and a second phase comprising application of ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof. 
     
     
         4 . The method of  claim 3 , wherein said application of radiofrequency heating is for about at least 5-10 seconds, 1-30 minutes, 5-30 minutes, or 20-240 minutes. 
     
     
         5 . The method of  claim 3 , wherein said application of ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof, is for about at least 3-30 minutes, 5-30 minutes, or 3-4 hours. 
     
     
         6 . The method of  claim 1 , wherein said electromagnetic energy is applied at a power of 100-1000 W, 1 KW-10 KW, or 5 KW-1 MW. 
     
     
         7 . The method of  claim 1 , wherein said radiofrequency comprises a frequency between about 1-900 MHz, 300 kHz-3 MHz, 3-30 MHz, 30-300 MHz, 13, 13.56, 27, 27.12, 40, or 40.68 MHz. 
     
     
         8 . The method of  claim 1 , wherein said radiofrequency penetrates the biomass to about 0.001 to 2.0 meters thickness. 
     
     
         9 . The method of any one of  claims 1 - 8 , wherein said biomass is heated to a temperature of at least about 1-300° C., 50° C.-100° C., 60° C.-130° C., 80° C.-175° C., or 100° C.-240° C. 
     
     
         10 . The method of  claim 1 , wherein said biomass is treated with radiofrequency for at least about 1 minute to 100 hours, 1-60 minutes, 1-24 hours, 5-10 minutes, 5-30 minutes, 10-50 minutes, 5 minutes to 3 hours, 1-3 hours, 2-4 hours, 3-6 hours, or 4-8 hours. 
     
     
         11 . The method of any one of  claims 1 - 10 , wherein said method further comprises washing the treated biomass. 
     
     
         12 . The method of  claim 11 , wherein said washing comprises washing the biomass with a liquid non-solvent for cellulose that is miscible with water and the ionic liquid (IL). 
     
     
         13 . The method of  claim 12 , wherein the liquid non-solvent used for washing is water, an alcohol, acetonitrile or a solvent which dissolves the IL and thereby extracts the IL from the biomass. 
     
     
         14 . The method of  claim 13 , wherein the alcohol is ethanol, methanol, butanol, propanol, or mixtures thereof. 
     
     
         15 . The method of  claim 13 , wherein said ionic liquid is recovered from the liquid non-solvent by a method selected from one or more of activated charcoal treatment, distillation, membrane separation, electro-chemical separation techniques, sold-phase extraction liquid-liquid extraction, or a combination thereof. 
     
     
         16 . The method of  claim 13 , wherein said ionic liquid is recovered from the liquid non-solvent by application of electromagnetic heating, optionally radiofrequency heating, that dehydrates the ionic liquid. 
     
     
         17 . The method of any one of  claims 1 - 16 , the method may further comprise reusing the recovered IL for treating more biomass, optionally wherein at least 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the IL is recovered. 
     
     
         18 . The method of  claim 1 , wherein the ionic liquid has a water content not exceeding about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25%. 
     
     
         19 . The method of any one of  claims 1 - 18 , wherein said method comprises incubating the biomass in a sufficient amount of an ionic liquid (IL) for a sufficient time to swell the biomass. 
     
     
         20 . The method of any one of  claims 1 - 19 , wherein the biomass is subjected to additional heating with agitation, ultrasonics heating, electromagnetic (EM) heating, convective heating, conductive heating, microwave irradiation, or a combination thereof, optionally with intermittent agitation during heating. 
     
     
         21 . The method of any one of  claims 1 - 20 , wherein the ionic liquid is molten at a temperature ranging from about 10° C. to 160° C. and comprises cations or anions. 
     
     
         22 . The method of  claim 1 , wherein the ionic liquid comprises a cation structure that includes ammonium, sulfonium, phosphonium, lithium, imidazolium, pyridinium, picolinium, pyrrolidinium, thiazolium, triazolium, oxazolium, or combinations thereof. 
     
     
         23 . The method of  claim 22 , wherein the ionic liquid comprises a cation selected from imidazolium, pyrrolidinium, pyridinium, phosphonium, ammonium, or a combination thereof. 
     
     
         24 . The method of  claim 1 , wherein the ionic liquid (IL) is 1-n-butyl-3-methylimidazolium chloride, 1-allyl-3-methyl imidazolium chloride, 3-methyl-N-butylpyridinium chloride, 1-ethyl-3-methyl imidazolium acetate, 1-ethyl-3-methyl imidazolium propionatem, or combinations thereof. 
     
     
         25 . The method of any one of  claims 1 - 24 , wherein said method is a continuous process. 
     
     
         26 . The method of any one of  claims 1 - 24 , wherein said method is a batch process. 
     
     
         27 . The method of any one of  claims 1 - 26 , wherein the conditions of said biomass undergoing radiofrequency (RF) heating is monitored by means of sensors, optionally a liquid flow rate sensor, thermocouple sensor, temperature sensor, salinity sensor, or combinations thereof. 
     
     
         28 . The method of any one of  claims 1 - 27 , wherein said method comprise adjusting the amount of ionic liquid, the time of incubation, or the temperature of the biomass. 
     
     
         29 . The method of any one of  claims 1 - 28 , wherein the biomass is not dissolved in the ionic liquid. 
     
     
         30 . The method of any one of  claims 1 - 28 , wherein the biomass is dissolved in the ionic liquid. 
     
     
         31 . The method of  claim 30 , wherein said dissolved biomass, optionally cellulose or hemicellulose, is regenerated by the use of anti-solvents. 
     
     
         32 . The method of  claim 31 , where said anti-solvent is water, methanol, ethanol, acetate, or mixtures thereof. 
     
     
         33 . The method of any one of  claims 1 - 32 , wherein said method further comprises treating said treated biomass with biochemical reagents, optionally an enzyme, to convert the cellulose and hemicellulose to sugars, optionally hexose and pentose sugars. 
     
     
         34 . The method of  claim 33 , wherein the biochemical reagent used to convert the cellulose and hemicellulose is an enzyme, optionally an enzyme mixture of hemicellulases, cellulases, endo-glucanases, exo-glucanases, and 1-β-glucosidases. 
     
     
         35 . The method of  claim 34 , wherein said cellulase is cellobiohydrolase, endocellulase, exocellulase, cellobiase, endo-beta-1,4-glucanase, beta-1,4-glucanase, or mixtures thereof. 
     
     
         36 . The method of  claim 34 , wherein said hemicellulase is laminarinase, lichenase, xylanase, or mixtures thereof. 
     
     
         37 . The method of  claim 34 , wherein said enzyme mixture further comprises xylanases, arabinases, or mixtures thereof. 
     
     
         38 . The method of  claim 33 , wherein said biochemical reagents are thermophilic enzymes, optionally enzymes that are active up to about 70° C. 
     
     
         39 . The method of  claim 33 , wherein said biomass is heated to at least about 50-100° C., 40° C., 55° C., or 70° C. 
     
     
         40 . The method of  claim 33 , wherein said sugars are converted to renewable fuels, chemicals and materials, optionally ethanol, butanol, lactic acid, gasoline, biodiesel, methane, hydrogen, electricity, plastics, composites, protein, drugs, fertilizers or other components thereof. 
     
     
         41 . The method of  claim 40 , wherein said chemicals are succinic acid, glycerol, 3-hydropropoionic acid, 2,5-dimethylfuran (DMF), 5-hydroxymethyl furfural (HMF), furfural, 2,5-furandicarboxylic acid, itaconic acid, levulinic acid, aldehydes, alcohols, amines, terephthalic acid, hexamethylenediamine, isoprene, polyhydroxyalkanoates, 1,3-propanediol, or mixtures thereof. 
     
     
         42 . The method of any one of  claims 1 - 41 , wherein said method further comprises recovering the enzymes. 
     
     
         43 . The method of any one of  claims 1 - 41 , wherein said treatment produces a solid residue comprising proteins and lignin. 
     
     
         44 . The method of  claim 43 , wherein the lignin is converted to fuels, chemicals, polymers, or mixtures thereof. 
     
     
         45 . The method of any one of  claims 1 - 44 , wherein said method further comprises treating said treated biomass with chemical reagents to convert the cellulose and hemicellulose to sugars, optionally hexose and pentose sugars. 
     
     
         46 . The method of  claim 45 , wherein said sugars are converted to chemicals, optionally succinic acid, glycerol, 3-hydropropoionic acid, 2,5-dimethylfuran (DMF), 5-hydroxymethyl furfural (HMF), furfural, 2,5-furandicarboxylic acid, itaconic acid, levulinic acid, aldehydes, alcohols, amines, terephthalic acid, hexamethylenediamine, isoprene, polyhydroxyalkanoates, 1,3-propanediol, or mixtures thereof. 
     
     
         47 . A method for disruption of the structure of a lignocellulosic biomass comprising incubating a biomass in an ionic liquid (IL) to swell the biomass and applying radiofrequency (RF) heating and ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof. 
     
     
         48 . A method for conversion of the carbohydrates of biomass to sugars comprising:
 (a) mixing biomass in an ionic liquid (IL) to swell said biomass;   (b) applying radio frequency (RF) heating to the biomass to heat to a target temperature range, optionally 50-220° C.;   (c) applying ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof, to the biomass to maintain the biomass at said target temperature range;   (d) washing the treated biomass;   (e) hydrolyzing the treated biomass to yield sugars, optionally pentose and hexose sugars, and release proteins and lignin.   
     
     
         49 . A method for the conversion of cellulose to sugar comprising
 (a) mixing biomass in an ionic liquid (IL) to swell said biomass;   (b) applying radio frequency (RF) heating to the biomass to heat to a target temperature range, optionally 50-220° C.;   (c) applying ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof, to the biomass to maintain the biomass at said target temperature range;   (d) precipitating amorphous cellulose and/or cellulose of reduced crystallinity by admixture with an anti-solvent; and   (e) adding cellulase to the cellulose precipitate under conditions which promote the hydrolysis of cellulose to sugars.   
     
     
         50 . A method for treatment of biomass comprising
 (a) incubating a biomass in a sufficient amount of an ionic liquid (IL) for a sufficient time and temperature to swell the biomass, optionally without dissolution of the biomass in the IL;   (b) applying radio frequency (RF) heating to the biomass to heat to a target temperature range, optionally 50-220° C.;   (c) applying ultrasonic heating to the biomass to maintain the biomass at said target temperature range;   (d) washing the treated biomass with a liquid non-solvent for cellulose that is miscible with water and the IL; and   (e) contacting said washed treated biomass with an aqueous buffer comprising enzymes capable of hydrolyzing cellulose and hemicellulose to produce sugars, optionally hexose and pentose sugars.   
     
     
         51 . The method of any one of  claims 47 - 51 , wherein the liquid non-solvent used for washing is water, an alcohol, acetonitrile or a solvent which dissolves the IL and thereby extracts the IL from the biomass. 
     
     
         52 . The method of  claim 51 , wherein the alcohol is ethanol, methanol, butanol, propanol, or mixtures thereof. 
     
     
         53 . The method of any one of  claims 47 - 51 , wherein the method further comprises recovering the IL from the liquid non-solvent by a method selected from activated charcoal treatment, distillation, membrane separation, electro-chemical separation techniques, sold-phase extraction, liquid-liquid extraction, or a combination thereof. 
     
     
         54 . The method of any one of  claims 47 - 51 , wherein said treatment produces a solid residue comprising proteins and lignin. 
     
     
         55 . The method of  claim 54 , wherein the lignin is converted to fuels, chemicals, polymers, or mixtures thereof. 
     
     
         56 . The method of any one of  claims 47 - 55 , wherein said wash is recovered and treated with RF heating to dehydrate the ionic liquid. 
     
     
         57 . A method of acidolysis of biomass comprising
 (a) mixing biomass in an ionic liquid (IL) to swell said biomass;   (b) adding an acid, optionally sulfuric acid, hydrochloric acid, nitric acid, or phosphoric acid, optionally lowering the pH of the biomass below pH 7, optionally a pH between 1-6;   (c) applying radio frequency (RF) heating to the biomass to heat to a target temperature range, optionally 50-220° C.;   (d) applying ultrasonic heating, electromagnetic (EM) heating, convective heating, conductive heating, or combinations thereof, to the biomass to maintain the biomass at said target temperature range;   (e) optionally washing the treated biomass; and   (f) recovering sugars, optionally pentose and hexose sugars, and released proteins and lignin.   
     
     
         58 . The method of  claim 57 , wherein said method further comprises addition of a base, optionally NaOH or KOH to neutralize the pH of the biomass. 
     
     
         59 . The method of  claim 57 , wherein said biomass is agricultural residues, optionally corn stover, wheat straw, bagasse, rice hulls, or rice straw; wood and forest residues, optionally pine, poplar, douglas fir, oak, saw dust, paper/pulp waste, or wood fiber; algae; coal; cellulose, lignin, herbaceous energy crops, optionally switchgrass, reed canary grass, or miscanthus; lingocellulosic biomass, optionally comprising lignin, cellulose, and hemicellulose; plant biomass; or mixtures thereof. 
     
     
         60 . The method of  claim 57 , wherein said pH is about 1, 2, 3, 3.5, 4, 4.5, 5, 5.5, 5.8, 6, 6.5, or 6.8, 1-3, 2-4, 3-5, 2-6, 3.5-4.5, or 4-6. 
     
     
         61 . The method of  claim 57 , wherein said temperature is about 120° C., 130° C., 140° C., 150° C., 120° C.-150° C., 130° C.-140° C., or 100° C.-150° C. 
     
     
         62 . The method of any one of  claims 57 - 61 , wherein heating comprises at least two phases, a first phase comprising application of radiofrequency heating, electromagnetic heating, heating by use of a variable frequency in the electromagnetic spectrum, variable frequency heating, or a combination thereof, and a second phase comprising application of ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof. 
     
     
         63 . The method of  claim 62 , wherein said application of radiofrequency is for about at least 5-10 seconds, 1-30 minutes, or 20-240 minutes. 
     
     
         64 . The method of  claim 62 , wherein said application of ultrasonics, electromagnetic (EM), convective, conductive heating, or combinations thereof, is for about at least 3-30 minutes or 3-4 hours. 
     
     
         65 . The method of any one of  claims 57 - 64 , wherein said electromagnetic energy is applied at a power of 100-1000 W, 1 KW-10 KW, or 5 KW-1 MW. 
     
     
         66 . The method of any one of  claims 57 - 64 , wherein said radio frequency comprises a frequency between about 1-900 MHz, 300 kHz-3 MHz, 3-30 MHz, 30-300 MHz, 13, 13.56, 27, 27.12, 40, or 40.68 MHz. 
     
     
         67 . The method of any one of  claims 57 - 64 , wherein said RF penetrates the biomass to about 0.001 to 2.0 meters thickness. 
     
     
         68 . The method of any one of  claims 57 - 64 , wherein said biomass is heated to a temperature of at least about 1-300° C., 50° C.-100° C., 60° C.-130° C., 80° C.-175° C., or 100° C.-240° C. 
     
     
         69 . The method of any one of  claims 57 - 68 , wherein said biomass is treated with RF for at least about 1 minute to 100 hours, 1-60 minutes, 1-24 hours, 5-10 minutes, 10-50 minutes, 5-30 minutes, 5 minutes to 3 hours, 1-3 hours, 2-4 hours, 3-6 hours, or 4-8 hours. 
     
     
         70 . The method of any one of  claims 57 - 69 , wherein said method further comprises washing the treated biomass. 
     
     
         71 . The method of  claim 70 , wherein said washing comprises washing the biomass with a liquid non-solvent for cellulose that is miscible with water and the IL. 
     
     
         72 . The method of  claim 71 , wherein the liquid non-solvent used for washing is water, an alcohol, acetonitrile or a solvent which dissolves the IL and thereby extracts the IL from the biomass. 
     
     
         73 . The method of  claim 72 , wherein the alcohol is ethanol, methanol, butanol, propanol, or mixtures thereof. 
     
     
         74 . The method of  claim 72 , wherein said ionic liquid is recovered from the liquid non-solvent by a method selected from one or more of activated charcoal treatment, distillation, membrane separation, electro-chemical separation techniques, sold-phase extraction liquid-liquid extraction, or a combination thereof. 
     
     
         75 . The method of  claim 72 , wherein said ionic liquid is recovered from the liquid non-solvent by application of electromagnetic heating, optionally radiofrequency energy, that dehydrates the ionic liquid. 
     
     
         76 . The method of any one of  claims 57 - 75 , comprising the further step of reusing the recovered IL for treating more biomass, optionally wherein at least 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the IL is recovered. 
     
     
         77 . The method of  claim 57 , wherein the ionic liquid has a water content not exceeding about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25%. 
     
     
         78 . The method of  claim 57 , wherein said method comprises incubating the biomass in a sufficient amount of an ionic liquid (IL) for a sufficient time to swell the biomass. 
     
     
         79 . The method of any one of  claims 57 - 78 , wherein the biomass is not dissolved in the ionic liquid. 
     
     
         80 . The method of any one of  claims 57 - 78 , wherein dissolved cellulose is regenerated by the use of anti-solvents. 
     
     
         81 . The method of  claim 57 , wherein the biomass is subjected to additional heating with agitation, ultrasonics heating, electromagnetic (EM) heating, convective heating, conductive heating, microwave irradiation, or a combination thereof, optionally with intermittent agitation during heating. 
     
     
         82 . The method of  claim 57 , wherein the ionic liquid is molten at a temperature ranging from about 10° C. to 160° C. and comprises cations or anions. 
     
     
         83 . The method of  claim 57 , wherein the ionic liquid comprises a cation structure that includes ammonium, sulfonium, phosphonium, lithium, imidazolium, pyridinium, picolinium, pyrrolidinium, thiazolium, triazolium, oxazolium, or combinations thereof. 
     
     
         84 . The method of  claim 83 , wherein the ionic liquid comprises a cation selected from imidazolium, pyrrolidinium, pyridinium, phosphonium, ammonium, or a combination thereof. 
     
     
         85 . The method of  claim 57 , wherein the ionic liquid (IL) is 1-n-butyl-3-methylimidazolium chloride, 1-allyl-3-methyl imidazolium chloride, 3-methyl-N-butylpyridinium chloride, 1-ethyl-3-methyl imidazolium acetate, 1-ethyl-3-methyl imidazolium propionatem, or combinations thereof. 
     
     
         86 . The method of any one of  claims 57 - 85 , wherein said method is a continuous process. 
     
     
         87 . The method of any one of  claims 57 - 85 , wherein said method is a batch process. 
     
     
         88 . The method of  claim 57 , wherein the conditions of said biomass undergoing RF treatment is monitored by means of sensors, optionally a liquid flow rate sensor, thermocouple sensor, temperature sensor, salinity sensor, or combinations thereof. 
     
     
         89 . The method of  claim 57 , wherein said method comprising adjusting the amount of ionic liquid, the time of incubation, the pH of the biomass, and the temperature of the biomass. 
     
     
         90 . A system for treating biomass comprising
 at least one electromagnetic (EM) oven; and   a moving platform comprising at least one conveyor belt, the moving platform configured to receive biomass on a conveyor belt at a first end of the moving platform, to move the biomass through an electromagnetic (EM) oven thereby treating the biomass by radio frequency treatment in combination with ionic liquids, and, optionally, comprising a sensor network coupled to a feedback system.   
     
     
         91 . A system for treating biomass comprising
 a mixing zone, wherein the biomass is admixed with an ionic liquid, coupled to an electromagnetic (EM), optionally radiofrequency, processing zone comprising a variable upper electrode and a fixed lower electrode, wherein the biomass is subjected to electromagnetic (EM), optionally radiofrequency, treatment, coupled to a washing zone, wherein the biomass is washed, and, optionally, comprising a sensor network coupled to a feedback system.   
     
     
         92 . A system for treating biomass comprising a reactor vessel coupled to a sensor network coupled to a feedback means for controlling the time, temperature, pressure, and water content of the interior of the reactor vessel.