For potential application of zeolite in environmental protection, the instantaneous adsorption of volatile nitrosamines in gas stream by zeolites was studied by a gas chromatography technique. Three volatile nitrosamines, N-nitrosodimethylamine, N-nitrosopyrrolidine, and N-nitrosohexamethyleneimine, were chosen as adsorbates. The influence of adsorption temperature, flow rate of gas stream, and the mixed nitrosamines on the adsorption of zeolites was examined. Furthermore, the adsorption isotherms of nitrosamines were fitted with the Freundlich equation for the first time. Zeolite NaY showed the highest capacity to capture the nitrosamines in the gas stream containing sidestream smoke from cigarettes at ambient temperature, providing an efficient candidate for protection of environment and public health.

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Dispersion of copper oxide via a solvent-free method enables mesoporous silica SBA-15 to become a versatile trap of nitrosamines, exhibiting a high capability to capture volatile nitrosamines and tobacco special nitrosamines (TSNA). 3%CuO/SBA-15 can remove 85% of N-nitrosopyrrolidine (NPYR) in gaseous flow, one fifth more than that by the analogous via one-pot method, while 5%CuO/SBA-15 traps all N-nitrosonornicotine (NNN) in solution with a concentration of 0.6 mmol l 21 , superior to NaY zeolite. The dispersion of the copper guest in SBA-15 is assessed by XRD, H 2 -TPR, NO 2 -TPD and UV-Vis methods.

Aluminum‐containing plugged mesoporous silica has been successfully prepared in an aqueous solution that contains triblock copolymer templates, nitrates, and silica sources but without using mineral acid. The acidity of the solution can be finely tuned from pH 1.4 to 2.8 according to the amount of the introduced aluminum species which ranged from an Al/Si molar ratio of 0.25/1 to 4.0/1. The aluminum nitrate additive in the starting mixture, along with the weak acidity produced by the nitrates, contributes to the formation of plugged hexagonal structures and the introduction of different amounts of aluminum species into the mesostructure. Characterization by X‐ray diffraction, transmission electron microscopy, and N2 sorption measurements show that the Al‐containing plugged silicas possess well‐ordered hexagonal mesostructures with high surface areas (700–860 m2 g–1), large pore volume (0.77–1.05 cm3 g–1) and, more importantly, combined micropores and/or small mesopores in the cylindrical channels. Inductively coupled plasma–atomic emission spectrometry results show that 0.7–3.0 wt % aluminum can be introduced into the final samples. 27Al MAS NMR results display that about 43–60% aluminum species are incorporated into the skeleton of the Al‐containing silicas and the amount of the framework aluminum increases as the initial added nitrates rises. Scanning electron microscopy images reveal that the directly synthesized Al‐containing plugged silica has a similar morphology to that of traditional SBA‐15. Furthermore, the Al‐containing plugged samples have excellent performances in the adsorption and the catalytic decomposition of isopropyl alcohol and nitrosamine. Finally, the direct synthesis method is used to produce plugged mesoporous silicas that contain other metals such as chromium and copper, and the resultant samples also show good catalytic activities.

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