Document Type : Original Research Article

Authors

• Ernee Noryana Muhamad ^{1, 2}
• Dian Wahyuni Md Bahrin ¹
• Khairunisa Mokhtara ¹

¹ Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia

² Catalysis Science and Technology Research Centre (PutraCAT), Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia

Abstract

To make the biodiesel competitive with petroleum diesel, cheap and abundant materials can be utilized as a catalyst and waste oils can be used as resources. In this research study, the potential of waste chicken eggshells was used as a catalyst to produce biodiesel from the rendered chicken fats (RCF). The calcium methoxide catalyst was prepared by calcining the waste eggshells at 900 °C in air for 4 h followed by treatment with methanol under reflux condition. The physico-chemical properties of the prepared catalyst were characterized using the X-ray diffraction (XRD) analysis, Brunner-Emmet-Teller (BET), field emission scanning electron microscopy (FE-SEM), and temperature programmed desorption of carbon dioxide (CO₂-TPD). Two-step process including, esterification and transesterification were employed to convert the RCF to fatty acid methyl ester (FAME). Esterification pretreatment with ferric sulfate successfully reduced 75.1% of the FFA content in RCF which enables high biodiesel production. Under the optimal reaction condition, the highest conversion of biodiesel was found to be 90.04% at 1:15 oil to methanol molar ratio, 3 wt% catalyst loading, and 2 h reaction time at 65 °C. The catalyst was successfully used for 4 consecutive cycles with less than 2 mg/kg of Ca was detected in the product.

Graphical Abstract

Keywords

• Rendered chicken fats
• Waste chicken eggshells
• Transesterification