Efficient photocatalytic esterification of waste cooking oil over empty fruit bunches ash-supported TiO2

• Published in: IRANIAN JOURNAL OF CATALYSIS
• Main Authors: Ibrahim, Siti Fadhilah; Shohaimi, Norshahidatul Akmar Mohd; Hir, Zul Adlan Mohd; Mastuli, Mohd Sufri; Hin, Taufiq Yap Yun; Ibrahim, Mohd Lokman
• Format: Article
• Language: English
• Published: OICC Press 2024
• Subjects: Chemistry
• Online Access: https://www-webofscience-com.uitm.idm.oclc.org/wos/woscc/full-record/WOS:001310537400009
• ISSN: 2252-0236; 2345-4865
• DOI: 10.57647/j.ijc.2024.1403.25

Biodiesel production from waste cooking oil (WCO) holds promise as a renewable and sustainable energy source. However, high levels of free fatty acids (FFAs) in WCO require efficient pretreatment before transesterification. Utilizing solar energy for heterogeneous catalytic reactions offers an alternative to thermal-driven processes. TiO(2)EFBA, synthesized via the wet impregnation method, exhibits distinctive physicochemical properties confirming the successful incorporation of titanium dioxide (TiO2) onto the metal oxides of empty fruit bunches ash (EFBA), thereby enhancing the catalyst's performance and stability. Results showed that TiO(2)EFBA exhibits superior FFA conversion compared to TiO2 alone. Under optimized reaction conditions, employing 4 wt% TiO(2)EFBA catalyst, 20:1 methanol to oil molar ratio, and 2 h reaction time at room temperature under Ultra Violet (UV) light, achieves a remarkable 78% conversion rate of FFAs in WCO. Mechanistic investigation reveals the crucial role of electron/hole (e-/h+) species in reducing FFAs by suppressing the e-/h+ mechanism. Notably, TiO(2)EFBA facilitates easy separation and can be reused for 10 cycles, demonstrating its stability as a heterogeneous photocatalyst.