Biofuel Composition and Method of Producing a Biofuel

Abstract

An emulsified biofuel composition comprising: (A) a continuous phase comprising about 50-95 wt % of at least one liquid oil of vegetable or animal origin or mixtures thereof; (B) a water-containing dispersed phase comprising about 1-50 wt % water; (C) about 1-25 wt % of hydroxyl-containing organic compound selected from the group consisting of mono-, di-, tri- and polyhydric alcohols, provided that when a monohydric alcohol is used there is also present at least one of tert-butyl alcohol, at least one C2-C4 alkylene glycol or a mixture of both; (D) about 0.05-10 wt % of at least one emulsifier; wherein the dispersed water-containing droplets have an average particle size of less than about 20 microns. The biofuel is prepared from these components by mixing under high shear conditions, preferably with ultrasonic energy. The emulsifier(s) preferably exhibit a hydrophilic-lipophilic balance of about 8.5 to about 18 and the biofuel includes a cetane enhancer and mixture of an alcohol and mono- or poly-alkylene glycol.

1 . A biofuel composition comprising an aqueous emulsion having:
 (A) a continuous phase comprising about 50 wt % to about 95 wt % of at least one liquid oil of vegetable or animal origin or mixtures thereof;   (B) a water-containing dispersed phase comprising about 1 wt % to about 50 wt % of water;   (C) about 1 wt % to about 25 wt % of a hydroxyl-containing organic compound selected from the group consisting of monohydric, dihydric, trihydric and polyhydric alcohols, provided that when a monohydric alcohol is present there is also present at least one of tert-butyl alcohol, at least one C2-C4 alkylene glycol or a mixture of both;   (D) about 0.05 wt % to about 10 wt % of at least one emulsifier;   
     wherein the dispersed phase comprises water-containing droplets having an average particle size of less than about 20 microns and wherein all amounts are expressed based on the total weight of the composition. 
   
   
       2 . The biofuel of  claim 1  wherein the at least one emulsifier exhibits a hydrophilic-lipophilic balance, HLB, of about 8.5 to about 18. 
   
   
       3 . The biofuel of  claim 2  wherein the at least one emulsifier is selected from the group consisting of polyethylene glycol-polypropylene glycol block copolymers, sorbitan monooleate, sorbitan monostearate, sorbitan monopalmitate, sorbitan monolaurate, polyoxyethylene (20) sorbitan trioleate, polyethylene (20) sorbitan monooleate, polyethylene (20) sorbitan monolaurate, and mixtures thereof. 
   
   
       4 . The biofuel of  claim 1  further comprising an effective amount of an additive to increase the cetane number of the biofuel composition. 
   
   
       5 . The biofuel of  claim 4  wherein the cetane additive is selected from the group consisting of peroxides, nitrates, nitrites, nitrocarbamates, and mixtures thereof. 
   
   
       6 . The biofuel of  claim 5  wherein the cetane additive is selected from the group consisting of substituted or unsubstituted, linear, branched or mixed linear or branched, alkyl or cycloalkyl nitrates having up to about 10 carbon atoms, and mixtures thereof. 
   
   
       7 . The biofuel of  claim 5  wherein the cetane additive is selected from the group consisting of dialkyl peroxides of the formula R1OOR2 wherein R1 and R2 are the same or different alkyl groups having 1 to about 10 carbon atoms, and mixtures thereof. 
   
   
       8 . The biofuel of  claim 5  wherein the cetane additive is selected from the group consisting of 2-ethylhexyl nitrate, di-tertiary-butyl peroxide and mixtures thereof. 
   
   
       9 . The biofuel of  claim 1  wherein the hydroxyl-containing organic compound includes at least one member selected from the group consisting of C1 to C4 straight and branched chain monoalcohols, C2 to C4 mono- and poly-alkylene glycols, derivatives of C2 to C4 mono- and poly-alkylene glycols provided that the molecular weights of such polyalkylene glycols are suitable for use in the fuel compositions, and mixtures thereof. 
   
   
       10 . The biofuel of  claim 9  wherein the alcohol is selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, and mixtures thereof. 
   
   
       11 . The biofuel of  claim 1  further comprising a supplementary low viscosity, low density combustible liquid selected from the group consisting of hydrocarbon solvents, paint thinner, turpentine, mineral spirits and mixtures thereof. 
   
   
       12 . A method of preparing an emulsified fuel composition comprising:
 (A) providing the following components in the amounts based on the total weight of the composition:
 (1) about 50 wt % to about 95 wt % of at least one liquid oil of vegetable or animal origin or mixtures thereof; 
 (2) water in an amount sufficient to produce a water-containing dispersed phase comprising about 1 wt % to about 50 wt % of water; 
 (3) about 1 wt % to about 25 wt % of a hydroxyl-containing organic compound selected from the group consisting of monohydric, dihydric, trihydric and polyhydric alcohols, provided that when a monohydric alcohol is present there is also present at least one of tert-butyl alcohol, at least one C2-C4 alkylene glycol or a mixture of both; and 
 (4) about 0.05 wt % to about 10 wt % of at least one emulsifier; 
   (B) mixing components (A)(1)-(A)(4) with one another under conditions of high shear, thus producing a dispersed phase comprising water-containing droplets having an average particle size of less than about 20 microns.   
   
   
       13 . The method of  claim 12  wherein said dispersed phase comprises water-containing droplets having an average particle size of about 0.1 to about 10 microns. 
   
   
       14 . The method of  claim 13  wherein the at least one emulsifier exhibits a hydrophilic-lipophilic balance, HLB, of about 8.5 to about 18. 
   
   
       15 . The method of  claim 14  wherein the at least one emulsifier is selected from the group consisting of polyethylene glycol-polypropylene glycol block copolymers, sorbitan monooleate, sorbitan monostearate, sorbitan monopalmitate, sorbitan monolaurate, polyoxyethylene (20) sorbitan trioleate, polyethylene (20) sorbitan monooleate, polyethylene (20) sorbitan monolaurate, and mixtures thereof. 
   
   
       16 . The method of  claim 13  including further providing an effective amount of an additive to increase the cetane number of the biofuel composition. 
   
   
       17 . The method of  claim 14  wherein the cetane additive is selected from the group consisting of peroxides, nitrates, nitrites, nitrocarbamates, and mixtures thereof. 
   
   
       18 . The method of  claim 12  wherein the hydroxyl-containing organic compound includes at least one member selected from the group consisting of C1 to C4 straight and branched chain monoalcohols, C2 to C4 mono- and poly-alkylene glycols, derivatives of C2 to C4 mono- and poly-alkylene glycols provided that the molecular weights of such polyalkylene glycols are suitable for use in the fuel compositions, and mixtures thereof. 
   
   
       19 . The method of  claim 12  wherein the components are provided and mixed substantially simultaneously. 
   
   
       20 . The method of  claim 16  wherein the water is premixed with the components other than the vegetable oil to produce an aqueous mixture and the aqueous mixture is thereafter mixed with the vegetable oil. 
   
   
       21 . The method of  claim 13  using high shear generating mixing equipment. 
   
   
       22 . The method of  claim 21  wherein high shear is generated using mixing equipment capable of generating and introducing ultrasonic energy into the mixture. 
   
   
       23 . The method of  claim 22  wherein the amount of emulsifier is from about 20% to about 90% of the amount emulsifier required to obtain the dispersed particle size in the absence of the use of ultrasonic energy. 
   
   
       24 . Emulsified fuel according to  claim 1  wherein the average droplet particle size is selected from the group consisting of about 0.01 to about 15 microns; 0.1 to about 10 microns; 0.5 to about 5 microns, and mixtures thereof. 
   
   
       25 . Emulsified fuel according to  claim 24  further comprising an effective amount of an additive to increase the cetane number of the biofuel composition. 
   
   
       26 . Emulsified fuel according to  claim 25  wherein the cetane additive is selected from the group consisting of peroxides, nitrates, nitrites, nitrocarbamates, and mixtures thereof. 
   
   
       27 . Emulsified fuel according to  claim 1  further comprising at least one member selected from the group consisting of thermal stabilizers, aging stabilizers, antioxidants, coloring agents, dyes, markers, odor modifying agents, rust inhibitors, inhibitors of gum formation, metal deactivators, upper cylinder lubricants, friction modifiers, detergents, bacteriostatic agents, fungicides, microbiocides and mixtures thereof. 
   
   
       28 . The emulsified fuel according to  claim 25  wherein the emulsifier is selected from the group consisting of polyethylene glycol-polypropylene glycol block copolymers, sorbitan monooleate, sorbitan monostearate, sorbitan monopalmitate, sorbitan monolaurate, polyoxyethylene (20) sorbitan trioleate, polyethylene (20) sorbitan monooleate, polyethylene (20) sorbitan monolaurate, and mixtures thereof and wherein the alcohol is selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, and mixtures thereof. 
   
   
       29 . The emulsified fuel according to  claim 28 , further comprising a supplementary low viscosity, low density combustible liquid selected from the group consisting of hydrocarbon solvents, paint thinner, turpentine, mineral spirits and mixtures thereof. 
   
   
       30 . The biofuel composition of  claim 1  comprising oil obtained from the seeds or fruits of plants or mixtures thereof. 
   
   
       31 . The method of  claim 12  comprising oil obtained from the seeds or fruit of plants or mixtures thereof. 
   
   
       32 . The biofuel of  claim 2  wherein the at least one emulsifier comprises a mixture of at least two emulsifiers wherein at least one of the two emulsifiers exhibits a low HLB value of about 1 to about 6 and at least one of the two emulsifiers exhibits a high HLB value of about 6 to about 20, provided that the low HLB value and the high HLB value are not both equal to 6. 
   
   
       33 . The biofuel of  claim 32  wherein: (I) the sum of (a) the weight of water and (b) the weight of hydroxyl-containing organic compound; divided by (II) the weight of vegetable and animal fat and oil is lower than about 0.25. 
   
   
       34 . The method of  claim 14  wherein the at least one emulsifier comprises a mixture of at least two emulsifiers wherein at least one of the two emulsifiers exhibits a low HLB value of about 1 to about 6 and at least one of the two emulsifiers exhibits a high HLB value of about 6 to about 20, provided that the low HLB value and the high HLB value are not both equal to 6. 
   
   
       35 . The method of  claim 34  wherein: (I) the sum of (a) the weight of water and (b) the weight of hydroxyl-containing organic compound; divided by (II) the weight of vegetable and animal fat and oil is equal to or less than about 0.25. 
   
   
       36 . An emulsified fuel mixture prepared from the following components: (A) 1500 parts vegetable or animal oil or fat; and (B) 900 parts water; and (C) 400 parts denatured ethanol 90 wt % (180 proof); (D) 30 parts of at least one component selected from the group consisting of (1) hydrogenated castor oil; (2) cetyl alcohol; and (3) a mixture of (1) and (2); and optionally further comprising 500 parts of a supplementary combustible liquid. 
   
   
       37 . A method for preparing an emulsified fuel mixture comprising: (I) mixing (A) 400 parts denatured, water-containing ethanol 90 wt % (180 proof); and, (B) 30 parts of at least one component selected from the group consisting of (1) hydrogenated castor oil; (2) cetyl alcohol; and (3) a mixture of (1) and (2) to form an additive; (II) mixing the additive with component (B) 900 parts water, to form a mixture (II); (III) adding mixture (II) with concurrent mixing to (D) 1500 parts vegetable or animal oil or fat to produce a substantially emulsified mixture.