Preparation of CYCU‐3/MCM‐41 Composites and Adsorption Properties for n‐Hexane

Abstract

Adsorption method is one of the effective technologies for treating VOCs. Compared with activated carbon, silicon‐based materials have well‐ordered pore structure, good thermal stability and non‐flammability. In this paper, CYCU‐3/MCM‐41 composites were prepared by hydrothermal method through mixing MCM‐41 powder in situ. The nitrogen adsorption isotherms, saturation adsorption and cyclic adsorption/desorption curves of n‐hexane on CYCU‐3/MCM‐41 composites were experimentally measured. The results displayed that the CYCU‐3/MCM‐41 (3) exhibited the largest BET specific surface area (1631 m2/g). And its n‐hexane adsorption capacity was 776 mg/g, which was 19.4 % higher than that of MCM‐41, 1.42 times that of activated carbon, and 2.64 times that of molecular sieve. The kinetic fitting results showed that the pseudo‐first order kinetic model can more precisely embody the n‐hexane adsorption process on CYCU‐3/MCM‐41 composites, and the W‐M intraparticle diffusion model confirmed that intraparticle diffusion was not the only control step for the adsorption rate of n‐hexane on CYCU‐3/MCM‐41 composites. In addition, the regenerative rate of CYCU‐3/MCM‐41 (3) was over 98.9 % after ten adsorption and desorption cycles of n‐hexane, showing good desorption performance and excellent structural stability, and proving its broad application prospect in the field of VOCs treatment.