Patent ID: 8507229

Claim:
An electrochemical method for simultaneously producing a biodiesel mixture comprising fatty acid alkyl esters and glycerol from free fatty acids (FFA) via esterification and from triglycerides via transesterification comprising: providing a electrodeionization catalytic reactor (EDICR) stack having an anode and a cathode and a plurality of alternating electrolyte chambers and esterification chambers positioned between the anode and cathode, wherein each esterification chamber is formed from a porous solid ion exchange resin wafer (IERW) interposed between a bipolar exchange membrane, and an anion exchange membrane, a first bipolar exchange membrane being positioned adjacent the cathode and spaced from the anion exchange membrane of a first esterification chamber to define a first electrolyte chamber between the first bipolar exchange membrane and the first esterification chamber; each subsequent electrolyte chamber in the plurality of electrolyte chambers being defined by a spacing between the bipolar exchange membrane of one esterification chamber and the anion exchange membrane of an adjacent esterification chamber; and wherein the anode is adjacent the bipolar membrane of a last esterification chamber in the plurality of esterification chambers; introducing an ion conducting solution comprising a hydroxide salt into the electrolyte chambers; introducing a feedstock and a lower alcohol in the esterification chambers, wherein the feedstock comprises: free fatty acids (FFA) and triglycerides; establishing an electric potential between the EDICR anode and cathode thereby creating a current across the stack that catalyzes the production of a biodiesel mixture within the esterification chambers via simultaneous esterification and transesterification, the formed biodiesel mixture comprising: fatty acid alkyl esters and glycerol, the current across the stack: promoting the reaction of triglycerides present in the feedstock with the lower alcohol in the presence of the IERW to produce alkyl esters and glycerol via transesterification; promoting the reaction of the FFA present in the feedstock with the lower alcohol in the presence of the IERW to produce fatty acid alkyl esters and water via esterification; causing at least a portion of the water created by the esterification reaction to split into protons and hydroxyl anions via electrodeionization in the presence of the IERW; wherein at least a portion of the formed hydroxyl anions catalyze the transesterification reaction between the lower alcohol and triglycerides to produce alkyl esters and glycerol; and wherein at least a portion of the formed protons catalyze the esterification reaction between the FFA and the lower alcohol to produce fatty acid alkyl esters.