title: Facile preparation of hierarchically porous diatomite/MFI-type zeolite composites and their performance of benzene adsorption: the effects of NaOH etching pretreatment.
abstract: Hierarchically porous diatomite/MFI-type zeolite (Dt/Z) composites with excellent benzene adsorption performance were prepared. The hierarchical porosity was generated from the microporous zeolite coated at the surface of diatom frustules and from the macroporous diatomite support. A facile NaOH etching method was employed for the first time to treat the frustule support, followed by hydrothermal growth of MFI-type zeolite at the surface of frustules previously seeded with nanocrystalline silicalite-1 (Sil-1). NaOH etching enlarged the pores on diatom frustules and further increased the coated zeolite contents (W(z)). The central macropore size of the diatom frustules increased from approximately 200-500 nm to 400-1000 nm after NaOH etching. The W(z) could reach 61.2%, while the macroporosity of the composites was largely preserved due to more voids for zeolite coating being formed by NaOH etching. The Dt/Z composites exhibited higher benzene adsorption capacity per unit mass of zeolite and less mass transfer resistance than Sil-1, evaluated via a method of breakthrough curves. These results demonstrate that etching of a diatomite support is a facile but crucial process for the preparation of Dt/Z composites, enabling the resulting composites to become promising candidates for uses in volatile organic compounds emission control.
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Yu
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China. Electronic address: yuanpeng@gig.ac.cn.
authors.forename: Peng
authors.initials: P
authors.lastname: Yuan
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Liu
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Liangliang
authors.initials: L
authors.lastname: Deng
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Yuan
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Tao
authors.affiliation: State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China.
authors.forename: Hefa
authors.initials: H
authors.lastname: Cheng
authors.affiliation: CAS Key Laboratory of Mineralogy and Metallogeny, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Wushan, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of Mineral Physics and Materials, Wushan, Guangzhou 510640, China.
authors.forename: Fanrong
authors.initials: F
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D000393:Air Pollutants / Q000737:chemistry*; D001554:Benzene / Q000737:chemistry*; D007692:Diatomaceous Earth / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D012972:Sodium Hydroxide / Q000737:chemistry*; D014961:X-Ray Diffraction; D017641:Zeolites / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D017641:Zeolites; D012972:Sodium Hydroxide; D007692:Diatomaceous Earth; C033787:diatomite; D001554:Benzene
keywords: Benzene adsorption; Composites; Diatomite; MFI-type zeolite; NaOH etching