On the lookout for a biodiesel esterification process that does not need to use methanol and produce a glycerin byproduct. The glycerin can be turned into ethanol, but if this can be avoided entirely it would be less energy and effort.
Greenline Industries, a biodiesel process technology provider, is developing a new process to esterify free fatty acids without using acid catalysts, according to the company’s Senior Process Engineer Gaurav Shah. He couldn’t give details on exactly what approach Greenline Industries’ new esterification process will use, but said in a couple of months, once patent protection is in place, the company will provide more details. Some biodiesel feedstocks, such as yellow grease and brown grease, contain high amounts of FFAs. If a biodiesel refinery’s business plan includes conversion of those FFAs to biodiesel, the conventional approach is to esterify the FFAs into biodiesel using an acid catalyst, such as sulfuric or hydrochloric acid and methanol, then turning the rest of the feedstock – the triglycerides – to methyl esters through conventional base transesterification. “Greenline has always had the philosophy of being a chemical and acid-free facility – besides sodium methylate and methanol,” Shah told Biodiesel Magazine. “The reason for maintaining this philosophy of being green without using unnecessary chemicals or acids is twofold. First, permitting acids is not an easy task in the U.S., especially when environmental laws are getting tougher. Secondly, acids and their toxic disposals counter our green approach.”