Development of Chromium-Impregnated Sulfated Silica as a Mesoporous Catalyst in the Production of Biogasoline from Used Cooking Oil via a Hydrocracking Process

Abstract

Abstract The production of biofuels as an alternative to fossil fuels has been a significant challenge until recently. The present work focuses on hydrocracking used cooking oil (UCO) into biogasoline over chromium impregnated on a sulfated mesoporous silica catalyst. The effects of varying sulfuric acid concentration, calcination temperature, and impregnated chromium content (wt%) were systematically studied in the synthesis process employing TEOS and NaHCO3 by sol-gel method. A sulfuric acid concentration of 2 M and calcination temperature of 600 ˚C produced an SO4-SiO2 catalyst with the best acidity of 8.46 mmol g-1. Variation of chromium content (wt%) of 1% had Cr/SO4-SiO2 catalyst with the best acidity of 8.57 mmol g-1. SiO2, SS 2-600, and Cr-SS 1 catalyst were tested for their performance in the hydrocracking of UCO into biogasoline at an optimum temperature of 450 °C, H2 gas flow rate of 20 mL min-1, and catalyst-to-feed ratio (wt%) of 1:100. Hydrocracking using Cr-SS 1 catalyst produced the most liquid product of 37.14% with the highest gasoline fraction selectivity of 29.38%.