Cerium incorporated into a mesoporous molecular sieve (MCM-41)

Abstract

The synthesis and characterization of a mesoporous molecular sieve (MCM-41) was studied due to its high surface area and large pore volume and to target potential applications in adsorption and catalysis. Rare earth elements have special chemical properties and are efficient promoters for supports. In this study, a mesoporous molecular sieve that incorporates the transition metal cerium (Ce-MCM-41) was synthesized using the hydrothermal method with the goal of improving the structural properties for adsorption. The molar composition of the obtained gel was 1CTMABr: 4SiO2: 1Na2O: 0.2Ce2O3: 200H2O. The pure mesoporous molecular sieve MCM-41 was also synthesized using the same method. The materials were characterized by the following techniques: XRD, BET/BJH, SEM/EDS, TG and FT-IR. A preliminary test to evaluate the materials as adsorbents to remove naphthenic acids present in jet fuel was performed. The results of the characterization showed that the incorporation of the metal cerium did not affect the MCM-41 structure and that mesporous materials were formed. Ce-MCM-41 exhibited good thermal stability, high specific surface area and large pore volume, which are characteristics of a good adsorbent. From the preliminary test, the adsorptive capacity increased by 60% with the incorporation of cerium in the MCM-41 structure.