The noncatalytic transformation of the crude lipid of Chlorella vulgaris (C vulgaris) into fatty acid methyl ester (FAME) via a thermo-chemical process was mainly investigated in this work. The crude lipid of C vulgaris was recovered by means of solvent extraction from C vulgaris cultivated in a raceway pond. The conventional catalyzed transesterification of crude lipid of C vulgaris is notably inhibited by the impurities contained in the crude lipid of C vulgaris. These impurities are inevitably derived from the solvent extraction process for C vulgaris. However, this work presents the noncatalytic transesterification of microalgal lipid into FAME, Which could be an alternative option. For example, the noncatalytic transformation of microalgal lipid into FAME provides evidence that the esterification of free fatty acids (FFAs) and the transesterification of triglycerides can be combined into a single step less susceptible to the impurities and with a high conversion efficiency (similar to 97%). (C) 2012 Elsevier Ltd. All rights reserved.