Experimental investigation on supercritical water partial oxidation of ethanol: Explore the way to complete gasification of ethanol

Supercritical water partial oxidation (SCWPO) is a green method of resource utilization of organic waste, and ethanol is one typical model compound of organic waste. At present, the detailed experimental study and mechanism of SCWPO of ethanol are still unknown. In this paper, SCWPO experiments of ethanol were investigated systematically in quartz batch reactors. The results showed that the increasing temperature and decrease in feed concentration promoted the gas yield and carbon gasification efficiency (CE) significantly. CE and gas yield significantly increased with reaction time before 60 s and stabilized between 120 s and 180 s. In particular, CE was close to 100% when the temperature was 700 °C at the reaction time of 180 s. The increasing oxidant equivalent ratio (ER) could improve CE while the gas yield reached the maximum value at ER = 0.1. Although ethanol was almost gasified completely, the thermodynamic equilibrium was still not reached within the researched reaction time (180 s). Finally, a detailed SCWPO mechanism of ethanol was proposed.