The effect of acid leaching time in modifying natural zeolite as catalyst for toluene steam reforming

Abstract

Tar accumulation can result in blockage, corrosion, and poisoning of catalyst. One of the methods applicable for tar removal is by using a catalyst that enhances steam reforming reaction. In this study, natural zeolites were modified for the use as tar steam reforming catalyst. This study also covers characterizing the modified natural zeolite by ion exchange and acid leaching, and measuring its activity as toluene steam reforming catalyst. The XRD pattern showed that natural zeolite contains three crystalline phases, i.e. mordenite, clinoptilolite, and heulandite. The main structure of the mordenite phase was also detected by using FTIR analysis on T-O stretching band with the range of 1045-1075 cm-1. The zeolite modification by ion exchange and acid leaching resulted in decreasing content of impurities, such as Na and K, and the decrease in crystallinity from 68.8% to 61.8%. The surface area increased from 16 m2/g to 31.4 m2/g and 161.8 m2/g for ZMH (after ion exchange), ZM3 (after acid leaching for 3 hour), and ZM6 (after acid leaching for 6 hour) respectively. Theses catalyst gave toluene conversion of 30.5% to 42.6% and 54% respectively.