Heterogeneous catalyst for transesterification and method of preparing same

Abstract

A transesterification catalyst that is heterogeneous and a method for preparing said transesterification catalyst are provided. The catalyst can be used in a variety of transesterification reactor configurations including CSTR (continuous stirred tank reactors), ebullated (or ebullating) beds or any other fluidized bed reactors, and PFR (plug flow, fixed bed reactors). The catalyst can be used for manufacturing commercial grade biodiesel, biolubricants and glycerin.

What is claimed is: 
     
       1. A method of preparing alkyl ester using a transesterification catalyst, the method comprising:
 providing a transesterification catalyst having the formula Z x Q y (PO 4 ) n H 2 O, wherein:   Z is selected from the group consisting of sodium and lithium,   Q is selected from the group consisting of calcium and barium,   x is a rational number in the range from 0.5 to 4,   y is a rational integer in the range from 2 to 8, and   n is a rational integer in the range from 4 to 8; and wherein the transesterification catalyst having the formula Z x Q y (PO 4 ) n H 2 O is supported on a ceramic substrate; and   reacting one or more triglycerides and an alcohol in the presence of the catalyst and converting the triglycerides and alcohol to alkyl ester and glycerin.   
     
     
       2. The method of  claim 1 , wherein the triglycerides comprise triglyceride-containing fats and/or oils. 
     
     
       3. The method of  claim 1 , wherein the converting of triglycerides comprises producing essentially complete conversion of the triglycerides to alkyl ester and glycerin. 
     
     
       4. The method of  claim 1 , further comprising:
 separating the glycerin from the alkyl ester and catalyst;   iltering the alkyl ester to recover the catalyst; and   distilling the unreacted alcohol from the alkyl ester and the glycerin.   
     
     
       5. The method of  claim 1 , wherein the method is at least partially performed in a continuous stirred tank reactor. 
     
     
       6. The method of  claim 1 , wherein the method is at least partially performed in a fixed bed reactor. 
     
     
       7. The method of  claim 1 , wherein the method is at least partially performed in a fluidized bed reactor. 
     
     
       8. The method of  claim 1 , wherein the alkyl ester is capable of being used as biodiesel fuel. 
     
     
       9. The method of  claim 1 , wherein the alkyl ester is capable of being used as biodiesel additive to conventional diesel fuel. 
     
     
       10. The method of  claim 1 , wherein the alkyl ester is capable of being used as a biolubricant additive to other lubricants. 
     
     
       11. The method of  claim 1 , wherein the alkyl ester is capable of being used as a biolubricant. 
     
     
       12. A method of facilitating a transesterification reaction comprising:
 using a reusable transesterification catalyst in the transesterification reaction,   wherein the reusable transesterification catalyst is recovered from a transesterification product comprising an alkyl ester,   and wherein the reusable transesterification catalyst is supported on a ceramic substrate,   and wherein the reusable transesterification catalyst comprises a double metal salt having the formula Z x Q y (PO 4 ) n H 2 O, wherein:
 Z consists of potassium, 
 Q consists of calcium, 
 x is a rational number in the range from 0.5 to 4, 
 y is a rational integer in the range from 2 to 8, and 
 n is a rational integer in the range from 4 to 8.