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A sulfonic acid-functionalized mesoporous polymer (MP-SO3H) catalyst was prepared via post-synthetic modification of mesoporous polydivinylbenzene.

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In this work, aromatization of C 5 -rich light naphtha as feedstock obtained from the refinery of Hindustan Petroleum Corporation Ltd. (HPCL) was studied along with n-hexane (model compound for light naphtha) over non-noble metal oxide based catalyst; ZnGa/ZSM-5. Zeolite ZSM-5 was modified with zinc and gallium by co-impregnation method. High aromatic yields were obtained over modified ZSM-5 catalysts due to dissociative chemisorption of alkanes resulting in dehydrogenation/ aromatization. The effect of acid sites on aromatization was studied by varying SiO 2 /Al 2 O 3 ratio (SAR) of ZSM-5 and correlated with the temperature programmed desorption of am-monia (NH 3 -TPD) studies. Optimized catalyst composition was further used for aromatization of n-pentane, n-heptane and light naphtha from a refinery. The Zn-GaÀH-ZSM-5 catalyst produced aromatics in high yields (64.8 % for light naphtha), especially high quantities of toluene with toluene/benzene ratio (T/ B)~2. From the aromatization studies, it could be envisaged that a proper balance of acid sites with dehydrogenation function is required to achieve maximum aromatic yield. Nitrogen was found to be a better carrier gas compared to hydrogen for aromatization of light naphtha.

A novel Zn–Sn composite oxide is reported as a solid bifunctional catalyst for glycerol carbonylation to give glycerol carbonate in high yields. It was prepared by coprecipitation, solid‐state and evaporation methods. Physico‐chemical properties of the catalysts were investigated by XRD, N2 sorption, temperature‐programmed desorption, SEM, and TEM techniques. Coprecipitation was found to be better than the other two methods for carbonylation of glycerol. Higher activity of the catalyst was attributed to a high amount of active sites. A series of Zn–Sn composite oxides with different metal contents and effect of calcination on glycerol carbonate synthesis were also studied. The correlation of activity with total active sites of the catalyst was obtained. Zn–Sn composite catalyst with Zn/Sn molar ratio=2:1 calcined at 600 °C exhibited 96.0 % glycerol conversion with 99.6 % selectivity towards glycerol carbonate under optimized reaction conditions. The catalyst was recycled four times with a marginal decrease in activity.