Gasification of refinery oily sludge using supercritical water technology: Influence of combination of acetic acid and Pt/Al2O3 catalyst

Abstract

To mitigate the environmental drawbacks associated with fossil fuels, the utilization of supercritical water gasification (SCWG) technology offers a promising approach to produce clean fuel gas, specifically H2-rich gas, from oily sludge. This study incorporates the use of Pt/Al2O3 as a catalyst and acetic acid as a gasification promoter. The impact of various operational factors, namely temperature (ranging from 400° to 600°C), feed concentration (10–30 wt%), catalyst to feed mass ratio (0−1), and acetic acid to feed mass ratio (0–0.40), was explored using Box-Behnken design. The results revealed that acetic acid and Pt/Al2O3 catalyst exert a positive influence on H2 production. Optimal conditions for the typical oily sludge with an initial concentration of 10.80 wt% resulted in the highest H2 yield (1.46 mmol.g-feed−1) at a temperature of 600 °C, an acetic acid to feed mass ratio of 0.19, and a catalyst to feed mass ratio of 0.85.