Studied on the mechanism of acid-base synergistic pyrolysis of waste cooking oils to superior quality biofuel

This paper proposes the acid-base synergy law in the catalytic cracking of waste cooking oil using acid-base dual-functional SBA-15 as the catalyst. By investigating the influence of different acid and base active components on the catalytic performance, combined with the physical properties of the catalyst itself, the acid-base synergy law was obtained. According to XRD and N 2 adsorption and desorption, the material loaded with acid-base active components has typical mesoporous SBA-15 structural characteristic peaks and Langmuir Ⅳ isotherm. On this basis, the acid-base dual-functional catalyst SBA-15@CaO@Mn was synthesized by the impregnation method, and the rationality of the obtained rule was verified by research the catalytic performance of SBA-15@CaO@Mn on the cracking of waste cooking oil, whose acid value is 16.8 mg KOH·g −1 , H/Ceff is 1.72, calorific value is as high as 43.17 MJ/kg. Through GC-MS analysis of liquid and gas phase products, the carbon coupling mechanism of acid-base cooperative cracking was obtained. This research provides theoretical guidance for effective deoxygenation in the catalytic cracking process of waste cooking oil in the future. • The acid-base dual-function catalyst SBA-15@CaO@Mn was synthesized. • Biofuel was obtained by acid-base synergistic pyrolysis of waste cooking oils. • The influence of acid and base active components was investigated. • Biofuel was of low acid value and oxygen content. • The catalyst has good reuse performance.