Prof. FANG Zhen and his team of Xishuangbanna Tropical Botanical Garden (XTBG) conducted a study aiming to directly produce biodiesel from oils with high acid value without any pretreatment using activated nanosized Mg-Al hydrotalcite (HT-Ca). With 5 wt% HT-Ca, 160 oC, 30/1 methanol/oil molar ratio and 4 h, 93.4% Jatropha biodiesel yield was obtained with an acid value (AV) of 6.3 mg KOH/g with 4 cycles (biodiesel yield > 86%). Soybean biodiesel yield reached 92.9% even from oil with high AV of 12.1 mg KOH/g.
CAS news release, June 25, 2015