Biofuel production using nanozeolite catalyst

Abstract

A method of converting biovapors to biofuel includes directing biovapors derived from decomposition of biomass, said biovapors comprising at least C5 and C6 compounds, into a catalytic reaction chamber; and contacting the biovapors with a catalyst composition comprising a nanozeolite.

1 . A method of converting biovapors to biofuel, comprising:
 directing biovapors derived from decomposition of biomass, said biovapors comprising at least C5 and C6 compounds, into a catalytic reaction chamber separate from the decomposed biomass; and   contacting the biovapors with a catalyst composition comprising a nanozeolite.   
     
     
         2 . The method of  claim 1 , wherein the C5 and C6 compounds are cyclic. 
     
     
         3 . The method of  claim 1 , wherein at least 60% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μm. 
     
     
         4 . The method of  claim 1 , wherein at least 80% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μm. 
     
     
         5 . The method of  claim 1 , wherein at least 90% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 2 μm. 
     
     
         6 . The method of  claim 1 , wherein at least 25% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μm. 
     
     
         7 . The method of  claim 1 , wherein at least 40% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μm. 
     
     
         8 . The method of  claim 1 , wherein at least 50% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μm. 
     
     
         9 . The method of  claim 1 , wherein nanozeolite crystallite has a silica to alumina ratio in the range of 50-250. 
     
     
         10 . The method of  claim 1 , wherein the nanozeolite catalyst comprises ZSM-5. 
     
     
         11 . The method of  claim 1 , wherein the nanozeolite is selected from a group consisting of ZSM-5, beta-zeolite, modernite-zeolite, zeolite-Y and mixtures thereof. 
     
     
         12 . The method of  claim 1 , wherein the catalyst composition further comprises a non-zeolite binder. 
     
     
         13 . The method of  claim 1 , wherein the biovapors are contacted with a catalyst composition heated at a temperature in the range of 350° C.-500° C. 
     
     
         14 . The method of  claim 1 , wherein the biovapors are contacted with a catalyst composition at a weight hourly space velocity of 0.1-1.0 hr −1 . 
     
     
         15 . The method of  claim 1 , wherein contacting the biovapors with a catalyst composition comprises sequentially contacting the biovapors with two or more catalysts compositions. 
     
     
         16 . The method of  claim 15 , wherein the catalyst compositions are different. 
     
     
         17 . The method of  claim 15 , wherein the catalyst compositions are the same. 
     
     
         18 . The method of  claim 15 , wherein the catalyst compositions are subjected to different reaction conditions. 
     
     
         19 . The method of  claim 18 , wherein the temperature of the catalyst conditions are different. 
     
     
         20 . The method of  claim 19 , wherein the temperature of the first catalyst composition is lower than the temperature of the second catalyst composition. 
     
     
         21 . The method of  claim 15 , wherein the second catalyst is a guard catalyst and the biovapors are contacted with the guard catalyst prior to contacting the biovapors with the nanozeolite catalyst composition. 
     
     
         22 . The method of  claim 21 , wherein the guard catalyst is selected from the group consisting of a dehydration catalyst, decarboxylation catalyst, decarbonylation catalyst, and deoxygenation catalyst. 
     
     
         23 . The method of  claim 21 , wherein the guard catalyst is selected from the group consisting of (1) heterogeneous heteropolyacids (HPAs) and their salts, (2) natural clay minerals, such as those containing alumina or silica (including zeolites), (3) cation exchange resins, (4) metal oxides, (5) mixed metal oxides, (6) inorganic acids or metal salts derived from these acids such as metal sulfides, metal sulfates, metal sulfonates, metal nitrates, metal phosphates, metal phosphonates, metal molybdates, metal tungstates, metal borates, and (7) combinations of groups 1 to 6. 
     
     
         24 . The method of  claim 21 , wherein the guard catalyst comprises a nanozeolite. 
     
     
         25 . The method of  claim 21 , wherein the guard catalyst is selected from the group consisting of (1) alkali and alkaline metal or metal oxides or metal hydroxides supported catalysts, where in the alkali metals are Lithium, Sodium, potassium, magnesium, strontium, cesium and Rubidium (2) basic transition metal supported catalysts such as zinc oxide, copper oxides etc., (3) hydrotalcites or layered double hydroxide catalysts such as Mg 6 Al 2 (OH) 16 CO 3 .4H 2 O and (4) solid super basic catalysts such as KF on europium oxide, KF on hydrotalcites. 
     
     
         26 . The method of  claim 1 , wherein the biovapors are obtained from a decomposition process selected from chemical, thermal and biological decomposition processes. 
     
     
         27 . The method of  claim 26 , wherein the thermal process comprises pyrolysis. 
     
     
         28 . The method of  claim 26 , wherein the chemical process comprises acid hydrolysis. 
     
     
         29 . The method of  claim 26 , wherein pyrolysis comprises heating biomass at temperatures of less than 600° C. to generate pyrolysis vapors. 
     
     
         30 . The method of  claim 27 , wherein water or steam is injected into biomass during pyrolysis. 
     
     
         31 . The method of  claim 30 , wherein the ratio of steam to biomass is in the range of 0.5 to 0.9 (wt/wt). 
     
     
         32 . The method of  claim 1 , wherein the fuel yield is greater than 6.5%, or greater than 7.0% or greater than 7.5%, or greater than 8.0% or greater than 8.5% by weight of input biomass, or in the range of 6.5-12% by weight of input biomass. 
     
     
         33 . The method of  claim 1 , wherein the reaction is carried out without addition of a cosolvent, such as methanol, ethanol or dimethyl ether. 
     
     
         34 . The method of  claim 1 , wherein the fuel product contains less than 3 wt % benzene and less than 1 wt % durene. 
     
     
         35 . A catalyst system for conversion of biovapors into biofuel, comprising:
 a catalyst reactor comprising at least two catalyst compositions positioned and arranged for sequential contact with a vapor,   wherein the first catalyst comprises a guard catalyst selected to reduce oxygen content and increase the hydrogen content of an oxygenated C5 and C6 compound-containing biovapor, and   wherein the second catalyst comprises a nanozeolite catalyst wherein at least 90% of the zeolite crystallites have a largest dimension of less than or equal to 200 μm.   
     
     
         36 . The catalyst system of  claim 35 , wherein at least 25% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μm. 
     
     
         37 . The catalyst system of  claim 35 , wherein at least 40% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μm. 
     
     
         38 . The catalyst system of  claim 35 , wherein at least 50% of the crystallites of the nanozeolite catalyst have a largest dimension that is less or equal to 1 μm. 
     
     
         39 . The catalyst system of  claim 35 , wherein nanozeolite crystallite has a silica to alumina ratio in the range of 50-250. 
     
     
         40 . The catalyst system of  claim 35 , wherein the nanozeolite catalyst comprises ZSM-5. 
     
     
         41 . The catalyst system of  claim 35 , wherein the nanozeolite is selected from a group consisting of ZSM-5, beta-zeolite, modernite-zeolite, zeolite-Y and mixtures thereof. 
     
     
         42 . The catalyst system of  claim 35 , wherein the catalyst composition further comprises a non-zeolite binder. 
     
     
         43 . The catalyst system of  claim 35 , wherein the first and second catalyst compositions are different. 
     
     
         44 . The catalyst system of  claim 35 , wherein the first and second catalyst compositions are the same.