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The paper reports preparation, surface, and textural characterization of Cu and Ni modified MCM-41 and its application for hydrodehalogenation of chlorobenzene. A series of Cu/Ni modified MCM-41 samples were synthesized by the co-condensation method by varying the amount of Ni and further characterized by various physicochemical methods. The incorporation of metals in the framework of mesoporous silica matrix was confirmed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) studies showed the formation of uniform spherical particles on the support surface. The catalytic activity of the samples was evaluated toward the hydrodehalogenation reaction of chlorobenzene at room temperature. Samples containing Si/(Cu + Ni) = 10 showed the highest chlorobenzene (98%) conversion with 100% selectivity for benzene. Among the various solvents studied for the reaction, isopropyl alcohol gave the best results at 2 h of reaction time. The effect of various halogen substituent and different electron donating and withdrawing groups on chlorobenzene is also studied to optimize the reaction conditions. [ABSTRACT FROM AUTHOR]

A series of Cu salts of heteropoly acid (CuxH3−2xPW12O40) supported MCM-41 catalysts (CuxH3−2xPW12O40/MCM-41) was synthesized by wet impregnation method and thoroughly characterized by using various analytical techniques, viz., X-ray diffraction, UV−vis diffused reflectance spectroscopy (UV−vis DRS), nitrogen adsorption desorption, temperature-programmed reduction (TPR), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). From XRD and FT-IR studies, we confirmed that the Keggin structure of heteropoly acid (HPA) is retained in Cu salt of HPA. Heck vinylation was performed to examine the catalytic properties of the catalysts. The 50 wt % CuxH3−2xPW12O40/MCM-41 showed remarkable catalytic performance of phenyl iodide (98% conversion) to cinnamic acid in aqueous medium compared with MCM-41 and other catalytic systems. [ABSTRACT FROM AUTHOR]