沸石分子筛用于VOCs吸附脱除的应用研究进展

挥发性有机化合物（volatile organic compounds，VOCs）作为空气中有机污染物的主要成分，对环境与人类健康造成了严重的危害。吸附法可有效富集低浓度VOCs气体，成本低、易操作，是末端治理去除VOCs的主要技术。沸石分子筛具有高度有序、孔径可调的微孔孔道，可实现VOCs分子的选择性吸附，且热稳定性极佳，易于脱附再生，是一种优良的VOCs气体吸附剂。本文分别从沸石分子筛的结构性质、复合型分子筛吸附剂以及整体式分子筛吸附剂三方面详细介绍了沸石分子筛用于VOCs吸附脱除的研究进展。结果表明，变换骨架拓扑结构以及补偿阳离子类型，可实现对VOCs分子进行选择性吸附；提高结构疏水性可有效降低高湿度条件下水分子对VOCs的竞争吸附，增强分子筛吸附剂的环境适应性；通过孔道多级化或与其他介/大孔构建复合型吸附剂，可提高分子筛吸附剂的比表面积和孔容，增大对VOCs的吸附容量；沸石分子筛可构建为整体式吸附剂，相较于颗粒型吸附剂，其机械强度更高，应用性更强。文章还指出，作为整体式分子筛吸附剂的典型代表，分子筛转轮吸附技术在高通量、高压降等吸附工况条件下均表现出极佳的VOCs吸附脱除效率，已广泛应用于工业排放VOCs的有效治理。

Review of adsorptive removal of volatile organic compounds by zeolite

As the major pollutants in air, volatile organic compounds (VOCs) have caused serious damage to the environment and human health. Due to its low cost and easy operation, the adsorption technology has been considered as one of the effective solutions for the enrichment of low concentration of VOCs in air. Zeolites have showed unique selective adsorption ability in molecular scale due to their highly ordered micropores with adjustable pore sizes and excellent thermostability, which allows them to be high-performance adsorbent candidates for VOCs. Besides, the selective adsorption behavior of the micropore zeolites was mainly decided by the types of framework topology and balanced cation. The enhancement in structural hydrophobicity of zeolites could effectively reduce the competitive adsorption between VOCs and water molecules under high humidity. By introducing macro-/mesopores into zeolite crystals or constructing hybrid adsorbents with macro-/mesopores materials, the obtained hierarchical porous adsorbents possessed much larger specific surface areas and total pore volumes, resulting in an increased adsorption capacity of VOCs. Zeolites were easy to process by extrusion or coating on shaped substrates, and the obtained monolithic adsorbents revealed higher mechanical strength and better abrasive resistance than the original powders. As a representative, zeolite adsorbent rotor, which was constructed by cellular zeolite monoliths, was successfully used for the effective removal of VOCs from industrial emissions.