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Although free hydroxyl radical (·OH) generated on OMS-2-based catalysts during the catalytic ozonation process have been shown as important reactive oxygen species (ROSs) for toluene degradation, improvement of surface ·OH formation ability remains challenging. Here, Na, K, Rb, and Cs-OMS-2-SO 4 2-/ZSM-5 catalysts were prepared, characterized and evaluated for catalytic ozonation of toluene. Both characterizations and DFT calculations showed that the appropriate alkali metal introduction made the catalyst possess with appropriate crystalline, reducibility, and acidity, which was favorable for catalytic ozonation of toluene. Characterizations also showed that alkali metal introduction resulted in water molecule adsorption on Brönsted acid sites of the catalysts, which made water molecule activation by ozone to form ·OH more easily. The introduction of K+ content of ∼ 5.9 wt% yielded K-OMS-2-SO 4 2-/ZSM-5 catalyst with the highest Brönsted acid sites and thus formed the most ·OH among the five prepared catalysts. As a result, the catalyst exhibited excellent toluene conversion and CO x selectivity for catalytic ozonation of toluene at room temperature and ambient humidity. Furthermore, the catalytic activity of deactivated K-OMS-2-SO 4 2-/ZSM-5 catalyst was recovered after regeneration by a combination of water washing and heat treatment. Finally, a complete mechanism for toluene catalytic ozonation, catalyst deactivation, and regeneration was proposed. [Display omitted] • The alkali metal introduction promoted ·OH formation in OMS-2-SO 4 2-/ZSM-5 catalyst. • The increased ·OH facilitated toluene conversion over OMS-2-SO 4 2-/ZSM-5 catalyst. • A complete mechanism for toluene catalytic ozonation and deactivation was proposed. • A strategy for efficient regeneration of K-OMS-2-SO 4 2-/Z catalyst was developed. [ABSTRACT FROM AUTHOR]

Adsorptive removal of gas phase low concentration macromolecular organic component, represented by naphthalene, from the enclosed space using ordered mesoporous carbon (OMC) has been studied by molecular simulation and experimental investigation. The simulation results indicated that both adsorption capacity and adsorption stability of the OMCs for naphthalene decreased with the increase of pore sizes from 2 nm to 8 nm. Characterizations showed that the prepared OMCs had the pore structure similar to the simulated OMCs except for the rough surface. In particular, the adsorption performance of the prepared OMCs was significantly lower than that of the simulated OMCs when pore size was 2 nm and 3 nm, which was attributed to the rough inner surface of these adsorbents, blocking the narrow pore channels and significantly reducing the pore volume. OMC with pore size of 4 nm had the highest adsorption amount for naphthalene. The co-adsorption experiments in the presence of both naphthalene and toluene, acetone or water showed the adsorption performance of OMCs for naphthalene were almost unaffected by the presence of low concentration toluene and acetone, as well as high relative humidity. [Display omitted] • Adsorption of naphthalene by OMCs were investigated by simulation and experiment. • Realistic molecular models for OMCs were constructed by "delete atom" method. • The impact of pore structure on the adsorption of naphthalene was revealed. • OMC with pore size of 4 nm has the highest adsorption capacity for naphthalene. • OMCs show excellent adsorption selectivity and good moisture resistance. [ABSTRACT FROM AUTHOR]