Biolubricant base stock with improved low temperature performance: Ester complex production using housefly (Musca domestica L.) larval lipid

Lipid generated from housefly (Musca domestica L.) larvae fed by municipal waste is a renewable lipid resource, however, the low unsaturated degree prevents it from producing trimethylolpropane fatty acid triester as lubricant, due to its poor low-temperature performance. A new fatty acid esters complex consisting of trimethylolpropane fatty acid triester and 2-ethylhexyl fatty acid ester was produced from housefly larval lipid. Separated from molecular distillation, the acylglycerols were first trans-esterified into fatty acid methyl ester and then further trans-esterified with trimethylolpropane into trimethylol-propane esters. The purified trimethylolpropane fatty acid triester is with purity of 98.4% and further blended with 30 wt% 2-ethylhexyl fatty acid ester derived from housefly larval free fatty acid. The pour point was substantially lowered from -3 degrees C to -12 degrees C while the lubricity performance is within standard of ISO VG 32, with minor improvement of water separability compared with pure trimethylolpropane fatty acid triester. By blending two type bio-lubricants with different advantages on viscosity and pour point, the ester complex with favorable properties was produced using saturated non-food lipid source rather than unsaturated virginal vegetable oil. This study also offers a cleaner and energy-efficient approach for high value-added product production for non-food lipid industry. (C) 2020 Elsevier Ltd. All rights reserved.