Utilization of Ficus carica leaves as a heterogeneous catalyst for production of biodiesel from waste cooking oil

• Published in: Environmental science and pollution research international Vol. 26; no. 32; pp. 32804 - 32814
• Main Authors: Kamel, Dena A., Farag, Hassan A., Amin, Nevin K., Zatout, Ahmed A., Fouad, Yasmine O.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2019; Springer Nature B.V
• Subjects: Activated carbon; Alcohol; Alcohols; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Biodiesel fuels; Biofuels; Biofuels - analysis; Calcium carbonate; Catalysis; Catalysts; Conversion; Cooking; Cooking oils; Diesel; Earth and Environmental Science; Ecotoxicology; Electron microscopes; Environment; Environmental Chemistry; Environmental Health; Environmental science; Esterification; Ficus; Flash point; Fossil fuels; Fourier transforms; Infrared spectroscopy; Leaves; Oil wastes; Plant Leaves - chemistry; Plant Oils - chemistry; Potassium carbonate; Reaction time; Research Article; Scanning electron microscopy; Spectroscopy, Fourier Transform Infrared; Stirring; Viscosity; Waste Water Technology; Water Management; Water Pollution Control; X-Ray Diffraction; Renewable energy sources; Solid catalysts; Agricultural wastes; Non-edible oils; Alkali activation
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-019-06424-z

Biodiesel appears to be a possible substitute for non-renewable fossil fuels; however, its production requires the presence of a catalyst to accelerate the reaction. Serving the purpose of finding effective, cheap and environmentally safe, heterogeneous catalysts, this research used the fig leaves in three different forms, calcined, activated by KOH, and activated by both K 2 CO 3 and CaCO 3 . Their efficiency in biodiesel synthesis, from spent cooking oil, was examined and compared with that of activated carbon which has been previously investigated. The properties of different catalyst forms were specified using X-ray diffraction, scanning electron microscope and Fourier transform infrared spectroscopy. Operating parameters studied for the three catalysts were reaction time (from 30 to 180 min), alcohol-to-oil molar ratio (from 4:1 to 10:1), catalyst loading (from 0.5 to 5% by wt.), and stirring speed (from 100 to 400 rpm). The increase in reaction time, molar ratio, and catalyst loading proved to have a favorable effect on % conversion to biodiesel but to a certain degree; increasing the stirring speed augmented the conversion. At optimum conditions (2 h of heating, 6:1 alcohol-to-oil molar ratio, 1% by wt. catalyst loading, and 400 rpm stirring), fig leaves activated by KOH provided the highest conversion to biodiesel (92.73%). The measured properties of the produced biodiesel (density, viscosity, flash point, cloud point, and pour point) yielded encouraging results. Graphical Abstract