Methods for producing phase stable, reduced acid biomass-derived pyrolysis oils

Abstract

Methods for producing phase stable, reduced acid biomass-derived pyrolysis oils are provided. Biomass-derived pyrolysis oil having a determined water content no greater than about 30% by weight is provided. A base is mixed with the biomass-derived pyrolysis oil to produce reduced acid biomass-derived pyrolysis oil. A base is selected from an inorganic base or a nitrogen-containing base.

1 . A method for producing phase stable, reduced acid biomass-derived pyrolysis oil comprising the steps of:
 providing a biomass-derived pyrolysis oil having a determined water content no greater than about 30% by weight; and   mixing a base with the biomass-derived pyrolysis oil.   
     
     
         2 . The method of  claim 1 , wherein the step of mixing comprises selecting the base comprising an inorganic base selected from the group consisting of a metal oxide, a metal hydroxide, a metal alkoxide, and a metal carbonate of the alkali and alkaline earth metals, alkali and alkaline earth exchanged zeolites, a mixed metal oxide, and combinations thereof. 
     
     
         3 . The method of  claim 2 , wherein the step of mixing comprises selecting the metal oxide from the group consisting of calcium oxide, magnesium oxide, and combinations thereof. 
     
     
         4 . The method of  claim 2 , wherein the step of mixing comprises selecting a metal hydroxide from the group consisting of LiOH, NaOH, KOH, RbOH, CsOH, Mg(OH) 2 , Ca(OH) 2 , Sr(OH) 2 , Ba(OH) 2 , and combinations thereof. 
     
     
         5 . The method of  claim 2 , wherein the step of mixing comprises selecting a metal alkoxide from the group consisting of sodium ethoxide, potassium tert-butoxide, and combinations thereof. 
     
     
         6 . The method of  claim 1 , wherein the step of mixing comprises selecting a nitrogen-containing base comprising an amine, a tetraalkylammonium hydroxide, or combinations thereof. 
     
     
         7 . The method of  claim 6 , wherein the step of mixing comprises selecting the amine from the group comprising a dialkyl amine, a trialkyl amine, or combinations thereof. 
     
     
         8 . The method of  claim 7 , wherein the step of mixing comprises selecting an amine from the group consisting of pyrrolidine, morpholine, piperidine, N-methyl pyrrolidine, and NR 1 R 2 X wherein:
 R 1 , R 2  are selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, sec. butyl, pentyl, hexyl, cyclohexyl, and benzyl; and   X is selected from the group consisting of hydrogen, R 1 , and R 2 .   
     
     
         9 . The method of  claim 6 , wherein the step of mixing comprises selecting the tetraalkylammonium hydroxide from the group consisting of tetraethylammonium hydroxide, tetramethylammonium hydroxide, tetrapropylammonium hydroxide, and combinations thereof. 
     
     
         10 . The method of  claim 1 , further comprising the step of dissolving a solid base in an organic solvent to produce a base solution with the total organic solvent concentration in the base solution comprising about 40 to about 95% by volume, the organic solvent selected from the group consisting of methanol, ethanol, and combinations thereof. 
     
     
         11 . The method of  claim 1 , wherein the step of providing comprises:
 determining the water content of the phase stable, reduced acid biomass-derived pyrolysis oil; and   removing at least a portion of the water from the biomass-derived pyrolysis oil, the base, or both the biomass-derived pyrolysis oil and the base.   
     
     
         12 . The method of  claim 11 , further comprising removing additional water upon phase separation of the reduced acid biomass-derived pyrolysis oil. 
     
     
         13 . A method for producing phase stable, reduced acid biomass-derived pyrolysis oil from water-containing biomass-derived pyrolysis oil, the method comprising the steps of:
 selecting a base comprising either an inorganic base or a nitrogen-containing base;   removing at least a portion of the water from the water-containing biomass-derived pyrolysis oil, the base, or both; and   adding the base to the water-containing biomass-derived pyrolysis oil to produce reduced acid biomass-derived pyrolysis oil.   
     
     
         14 . The method of  claim 13 , wherein the step of selecting a base comprises selecting the inorganic base from the group consisting of metal oxides, metal hydroxides, metal alkoxides, metal carbonates of the alkali and alkaline earth metals, alkali and alkaline earth exchanged zeolites, mixed metal oxides, and combinations thereof. 
     
     
         15 . The method of  claim 14 , wherein the step of selecting a base comprises selecting the metal oxide from the group consisting of calcium oxide, magnesium oxide, and combinations thereof; the metal hydroxide from the group consisting of LiOH, NaOH, KOH, RbOH, CsOH, Mg(OH) 2 , Ca(OH) 2 , Sr(OH) 2 , Ba(OH) 2 , and combinations thereof; and the metal alkoxide from the group consisting of sodium ethoxide, potassium tert-butoxide, and combinations thereof. 
     
     
         16 . The method of  claim 13 , wherein the step of selecting a base comprises selecting the nitrogen-containing base comprising an amine, a tetraalkylammonium hydroxide, or combinations thereof, wherein the amine is selected from the group consisting of a dialkyl amine, a trialkyl amine, and combinations thereof, pyrrolidine, morpholine, piperidine, N-methylpyrrolidine, and NR 1 R 2 X wherein:
 R 1 , R 2  are selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, sec. butyl, pentyl, hexyl, cyclohexyl, and benzyl; and   X is selected from the group consisting of hydrogen, R 1 , and R 2 .   
     
     
         17 . The method of  claim 13 , further comprising removing additional water from the reduced acid biomass-derived pyrolysis oil upon phase separation thereof 
     
     
         18 . A method for producing phase stable, reduced acid biomass-derived pyrolysis oil, the method comprising the steps of:
 providing water-containing biomass-derived pyrolysis oil;   selecting a base adapted to be added to the water-containing biomass-derived pyrolysis oil to produce reduced acid biomass-derived pyrolysis oil;   determining a water content of the reduced acid biomass-derived pyrolysis oil;   wherein if the reduced acid biomass-derived pyrolysis oil is determined to have a water content greater than about 30 wt %, removing at least a portion of the water from the water-containing biomass-derived pyrolysis oil, the base, or both; and   adding the selected base to the water-containing biomass-derived pyrolysis oil.   
     
     
         19 . The method of  claim 18 , wherein the step of selecting a base comprises selecting a solid base, the method further comprising dissolving the solid base in an organic solvent. 
     
     
         20 . The method of  claim 18 , further comprising the step of removing additional water from the reduced acid biomass-derived pyrolysis oil upon phase separation thereof.