Role of ceria in CO2 adsorption on NaZSM-5 synthesized using rice husk ash

Ceria (3, 5, 7, 11, 19 wt%) impregnated NaZSM-5 was synthesized and studied for adsorption of CO₂. They were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), CO₂-temperature programmed desorption (CO₂-TPD) and Brunauer–Emmett–Teller (BET) techniques. The heat of the reaction (ΔH_r) derived from differential scanning calorimetry (DSC) analysis was 490 Btu/lb. XRD analysis showed a decrease in the intensity of patterns with the increase in the ceria loading but crystallization of ceria to larger size was clearly evident for 11 and 19% loading. The surface area decreased for 3 and 5% loading, but increased for 7, 11 and 19% loading illustrating difference in dispersion. The maximum adsorption capacity of CeO₂(5%)/NaZSM-5 was 130 mg/g of sorbent. Extraction of silica from the agricultural waste, rice husk, and its use in the zeolite synthesis was an advantage in this study. Hence, from the study it was concluded that ceria impregnated NaZSM-5 could be treated as a novel material for CO₂ adsorption, as they were regenerable and recyclable. This study can also be applied to all other zeolites.