Transesterification using isopropanol as a co-solvent for the production of green biodiesel fuel

Previously, we have conducted the transesterification using isopropanol (IPA) as a co-solvent for biodiesel fuel (BDF) production in the homogeneous condition (a single fatty acid methyl ester [FAME] phase). In this report, we investigated the transesterification kinetics by varying IPA amount and the optimum conditions for BDF production with 10 wt% IPA. In the IPA amount of 5 to 25 wt%, the transesterification proceeded in a heterogeneous condition (FAME and glycerol [GL] phases) as the GL phase was formed and separated from the FAME phase. The transesterification rate increased with the increase of IPA amount, and the correlation coefficient (r) between the rate constant and IPA amount was 0.97 (P < 0.05). The optimal conditions of transesterification for biodiesel production from canola oil with 10 wt% IPA were as follows: 1.0 wt% KOH, MeOH/oil molar ratio of 6:1, and a reaction temperature of 30 degrees C. The quality of biodiesel satisfied the JIS K2390 and EN 14214 standards. Transesterification using 10 wt% IPA co-solvent could facilitate the phase separation after the reaction, and the amount of waste was reduced. The recovery of IPA from FAME phase was >96%, hence IPA could be reused. These results indicated that IPA was a superior co-solvent for the BDF production from plant oil feedstocks. Novelty statement Isopropanol as a co-solvent for biodiesel production from canola oil was examined. Kinetic parameter of reaction rate was estimated. The transesterification proceeded rapidly with increase of isopropanol. The transesterification conditions were optimized for biodiesel production with 10 wt% of isopropanol.

Automated summary

In this study, isopropanol was used as a co-solvent for biodiesel production, showing an increase in transesterification rate with higher amounts of isopropanol. The optimal conditions for transesterification were found to enhance the reaction efficiency.