Biodiesel production from crude palm oil and evaluation of butanol extraction and fuel properties

Three principal variables, molar ratio of methanol to oil, amount of cataly st, and reaction temperature, affecting the yield of acid-catalyzed product ion of methyl ester (biodiesel) from crude palm oil were investigated. The biodiesel was then used as an extractant in batch and continuous acetone-bu tanol-ethanol fermentation, and its fuel properties and that of the biodies el-ABE product mix extracted from the batch culture analyzed. The optimized variables, 40:1 methanol/oil (mol/mol) with 5% H2SO4 (vol/wt) reacted at 9 5 degreesC for 9 h, gave a maximum ester yield of 97%. Biodiesel preferenti ally extracted butanol, and enhanced its production in the batch culture fr om 10 to 12 g l(-1). The fuel properties of biodiesel and the biodiesel-ABE mix were comparable to that of No.2 diesel, but their cetane numbers and t he boiling points of the 90% fractions were higher. Therefore, they could s erve as efficient No. 2 diesel substitutes, The biodiesel-ABE mixture had t he highest cetane number. (C) 2001 Elsevier Science Ltd. All rights reserve d.