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Spherical periodic mesoporous organosilica (SPMO) supported catalyst bearing covalently tethered Ni(II) α-diimine complex has been successfully prepared in one-pot protocol reducing tedious and sensitive preparation steps. The SPMO-supported catalyst showed high activities (>106 g-PE mol-Ni−1 h−1 bar−1) in the presence of various cocatalysts such as methylaluminoxane and common alkyl aluminums like ethylaluminum sesquichloride, methylaluminum dichloride and diethylaluminum chloride. The thermal stability of the catalyst was enhanced to a great extent by heterogenization and the resulting polyethylenes showed uniform morphology replicating catalyst shape.

The performance of vanadia-doped titania-pillared clay (V/Ti-PILC) in the selective catalytic oxidation of H 2 S was investigated in this study. A series of V/Ti-PILC with various amounts of vanadia were prepared and characterized. XRD analysis revealed the presence of titania anatase peak without any evidence of crystalline vanadia. V/Ti-PILC showed a very good catalytic performance towards H 2 S oxidation at temperatures ranging from 220–300 °C without the considerable emission of SO 2 . At 300 °C, all the catalysts showed high H 2 S conversion of about 85%. The H 2 S conversions over V/Ti-PILC increased with increasing vanadia content and temperature.

Mesoporous Si-MCM-41 and Al-MCM-41 molecular sieves in four Si/Al ratios 25, 50, 75 and 100 were synthesized under hydrothermal condition. 10 wt.%, 15 wt.% and 20 wt.% H 3 PW 12 O 40 (PW) was supported on Si-MCM-41 and characterized using powder X-ray diffraction (XRD), FT-IR, BET and TEM techniques. Geminal diacetates were synthesized from a variety of aromatic aldehydes including those carrying electron donating or withdrawing substituents in good yields. The relatively non-toxic nature of the catalyst, its ease of handling and its easy availability makes the procedure attractive for eco-friendly organic synthesis. 20 wt.% PW/MCM-41 was found to be more active than other catalyst used and have similar activity as that of unsupported heteropoly acids (HPAs).

Tungstophosphoric acids (HPA) act as an efficient heterogeneous catalyst for the simple, and environmentally friendly synthesis of acetals in microwave at shorter reaction time with moderate microwave power superior to liquid phase involving HPA and various other heterogeneous catalysts, where the reactants were refluxed with benzene/toluene solvents for longer duration. While aryl aldehydes acetals are often easily prepared from their respective ketones, many acetals from aryl alkyl and diaryl ketones have been less accessible because of electronic and steric factor. This paper pays a greener alternative route for the direct transformation of such wide range of ketones and aldehydes into their respective acetals in short reaction time with high selectivity and yield, without the need for solvents in contrast to conventional method.