Patent ID: 8288574

Claim:
A method for producing C 3 H 5 (OH) 3 and at least one of fatty acid methyl ester (FAME) and fatty acid ethyl ester (FAEE) from at least one of vegetable oils and animal fats by base-catalyzed transesterification of triglycerides with at least one of CH 3 OH and C 2 H 5 OH, the method comprising: mixing the at least one of vegetable oils and animal fats, the at least one of CH 3 OH and C 2 H 5 OH and at least one first catalyst in a first mixer so as to transesterify a portion of the triglycerides and provide a first mixture; separating in a first settler downstream of the first mixer, the first mixture into a first light phase containing at least one of FAME and FAEE and a first heavy phase containing C 3 H 5 (OH) 3 ; withdrawing the first light phase from the first settler and feeding the first light phase into a downstream second mixer; mixing the first light phase with at least one second catalyst in the second mixer so as to transesterify a further portion of the triglycerides and provide a second mixture; separating, in a second settler downstream of the second mixer, the second mixture into a second light phase containing at least one of FAME and FAEE and into a second heavy phase containing C 3 H 5 (OH) 3 ; withdrawing the second light phase from the second settler and mixing the second light phase with soapless C 3 H 5 (OH) 3 so as to provide a dispersion; separating the dispersion by density difference into a phase containing at least one of raw FAME and raw FAEE having an acid number of â‰¦0.5 and into a phase containing dissolved soaps and a catalyst and at least one of C 3 H 5 (OH) 3 , CH 3 OH and C 2 H 5 OH; mixing the at least one of raw FAME and raw FAEE with an aqueous acid so as to provide a third mixture; washing the third mixture in counterflow with water so as to provide a washed third mixture and a first aqueous phase containing at least one of CH 3 OH, C 2 H 5 OH, C 3 H 5 (OH) 3 and salts; expelling water contained in the washed third mixture so as to provide at least one of FAME and FAEE product; recirculating the second heavy phase from the second settler to the first mixer; combining the first heavy phase from the first settler with the first aqueous phase so as to obtain a first heavy phase mixture; separating the first heavy phase mixture into a first phase containing at least one of CH 3 OH and C 2 H 5 OH and into a second aqueous phase containing at least one of C 3 H 5 (OH) 3 and salts; recirculating the first phase into the first mixer; and evaporating water from the second aqueous phase and discharging raw C 3 H 5 (OH) 3 .