Surfactant-assisted direct biodiesel production from wet Nannochloropsis occulata by in situ transesterification/reactive extraction

Document Type: Research Paper

Authors

School of Chemical Engineering and Advanced Materials (CEAM), Newcastle University, NE1 7RU, United Kingdom

Abstract

This article reports an in situ transesterification/reactive extraction of Nannochloropsis occulata for fatty acid methyl ester (FAME) production using H2SO4, sodium dodecyl sulphate (SDS) plus H2SO4 and zirconium dodecyl sulphate (ZDS). A maximum 67 % FAME yield was produced by ZDS. Effect of inclusion of sodium dodecyl sulphate (SDS) in H2SO4 for FAME enhancement and water tolerance was also studied by hydrating the algae with 10 % - 30 % distilled water (w/w) dry algae. Treatment with SDS in H2SO4 increases the FAME production rate and water tolerance of the process. Inclusion of SDS in H2SO4 produced a maximum 98.3 % FAME yield at 20 % moisture in the algae. The FAME concentration began to diminish only at 30 % moisture in the algae. Furthermore, the presence of a small amount of water in the biomass or methanol increased the lipid extraction efficiency, improving the FAME yield, rather than inhibiting the reaction. 

Graphical Abstract

Surfactant-assisted direct biodiesel production from wet Nannochloropsis occulata by in situ transesterification/reactive extraction

Highlights

  • Surfactant assisted in situ transesterification of wet algae was studied.

  • A surfactant catalyst (“ZDS”) produced high yields in Nannochloropsis occulata.

  • Inclusion of SDS in H2SO4 increased FAME production in the wet algae.

  • The process was not adversely affected by water in the algae up to 20%. 

Keywords


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[9] Standard UNE-EN 14103, 2003. Determination of ester and linolenic acid methyl ester contents. Issued by Asociación Española de Normalización y Certificación, Madrid.