Catalyzed steam gasification of Cistus ladanifer biochar

Abstract

Gasification processes require the use of cheap and sustainable raw materials, as well as the optimization of the process, for a suitable commercial use. Cistus Ladanifer (rockrose) could be a suitable raw material for this purpose, as it grows spontaneously in Mediterranean regions, and might contribute to the economic development of these areas. In this research, a study about catalyzed gasification of Cistus Ladanifer biochar was carried out. The aim was to characterize the gaseous phase and to carry out a kinetic study. The experiments were carried out in a thermobalance connected to a gas chromatograph to quantify the exhaust gas. The operating variables studied were the initial carbon mass, temperature, steam partial pressure, the kind of catalyst (ionic or cationic), catalyst concentration and the method to incorporate the catalyst (impregnation or mixture). As a result, impregnation was the most effective way to mix the raw material and the catalyst, with K+ and CO32− as the most active cations and anions used in this experience, respectively. Temperature and steam partial vapor showed a positive effect on conversion and gas yield. The use of ideal models for gas-solid reactions showed acceptable results for the kinetic study.