Investigation of solid base catalysts for biodiesel production from fish oil
Abstract
A series of composite CaO-Ca3Al2O6 mixed oxides were investigated as potential catalysts for biodiesel synthesis from waste fish oil. Different Ca/Al ratios, in the range of 1.5 to 6 were studied, alongside pure CaO. The catalysts were characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM) and CO2-Temperature Program Desorption (TPD). The catalytic activity of the materials was studied for the transesterification reaction of cod liver oil with methanol at 65 °C, with 1:12 oil to methanol molar ratio and 10 wt% of catalyst. Over 97% conversion of the triglycerides to methyl esters was achieved for the 6Ca/Al catalyst after 2 h reaction time. This was similar to the performance of CaO. However, 6Ca/Al catalyst was reused successfully for seven consecutive tests, in contrast to CaO that was reused for only five tests, before it deactivated. Therefore, by incorporating the Ca3Al2O6, it was possible to enhance the stability of the catalytically active species and improve the lifetime of the catalyst. Post-test catalyst characterisation showed the formation of an intermediate phase (calcium diglyceroxide) that enhanced the catalyst’s performance and tolerance to air exposure and humidity. Finally, the catalyst deactivation, after seven cycles, took place due to the formation of Ca(OH)2 and CaCO3 species.
Citation
Papargyriou , D , Broumidis , E , de Vere-Tucker , M , Gavrielides , S , Hilditch , P , Irvine , J T S & Bonaccorso , A D 2019 , ' Investigation of solid base catalysts for biodiesel production from fish oil ' , Renewable Energy , vol. 139 , pp. 661-669 . https://doi.org/10.1016/j.renene.2019.02.124
Publication
Renewable Energy
Status
Peer reviewed
ISSN
0960-1481Type
Journal article
Description
The authors would like to acknowledge Innovate UK for funding. Additionally, the authors would like to thank Dr Gavin Peters for the TGA and ICP-OES measurements. Finally, we would like to thank the Engineering and Physical Sciences Research Council, University of St Andrews, and CRITICAT Centre for Doctoral Training for financial support [Ph.D. studentship to M.D.V.T, S.G, and E. B; Grant code: EP/L016419/1].Collections
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