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Solubilization of diphenyl diselenide (DPDS) was studied in CTAB, OPE-10 and SDS surfactant solutions at 298 K. Solubility of DPDS increases with increase in the surfactant concentration due to its solubilization in micelles. UV-Vis, H1 NMR and FT-IR spectroscopy was used to study the interaction, location of diphenyl diselenide in the micelle. The change in free energy for solubilization of DPDS in micellar media confirmed the favorable solubilizations in SDS, OPE-10 and CTAB solutions. The DPDS solubility was higher in OPE-10 and CTAB compared to SDS surfactant aqueous solutions. [ABSTRACT FROM AUTHOR]

In the present study, photocatalytic degradation of five different reactive dyes has been carried out using Ag doped TiO2 supported on coal fly ash (CFA) as a photo catalyst system (Ag‐TiO2/CFA). The photocatalysts were synthesized with varying the percentage of Ag and characterized by XRD, SEM and UV‐visible spectrophotometry. The photocatalytic activity of Ag‐TiO2/CFA photocatalysts was studied for the degradation of reactive dyes in presence of both UV and visible light sources. The degradation was monitored by absorbance measurements. It was found that 3 wt % of Ag doping could bring about maximum degradation (85–95 %) at 3–4 h in presence of visible light. The effect of various parameters such as initial concentration of dye, catalyst amount and pH of solution towards the degradation were studied and it was observed that in acidic conditions the degradation was maximum (pH=3.0) for all the dyes studied. Ability to degrade an industrial waste, use of CFA, a thermal power plant waste as support, small quantities of silver required and degradation under visible light are the environmental as well as economic advantages of this developed catalytic system. [ABSTRACT FROM AUTHOR]

Ionic liquids have been found to be suitable alternatives to volatile organic solvents in chemical transformation. Through a proper choice of cations and anions, the properties of an ionic liquid can be tuned so that it resembles an amphiphile. Such specially designed molecules are known as surface‐active ionic liquids (SAIL). Like conventional surfactants, SAIL also form aggregates in an aqueous medium. Studies show that the mixing of SAIL with conventional surfactants leads to synergistic micellization. However, very few reports are available on the application of such systems as reaction media. Present study focuses on the application of mixed micelles of 1‐tetradecyl‐3‐methylimidazol‐1‐ium bromide, ([C14mim]Br) with nonionic surfactant, Octylphenol ethoxylate with 10 moles of ethylene oxide (OPE‐10). Enhanced solubilization and selective catalytic oxidation of toluene using hydrogen peroxide as an oxidant and tungstic acid as a catalyst have been studied in detail using this system. [ABSTRACT FROM AUTHOR]

In the present study, ZnO modified with rare earth oxides GdxMn; M=Mo, V, W) were synthesized by hydrothermal process and their catalytic activity was tested in an oxidative cyclization reaction for the selective synthesis of quinazolinones. The catalysts were characterized by various techniques such as BET surface area analysis, XRD, SEM‐EDX, DSC‐TGA, ICP‐MS and elemental color mapping. 5 wt% Gd2MoO6/ZnO exhibited good catalytic activity and gave 60–91% of Quinazolin‐4(3H) ones in toluene. The catalysts could be reused at least four times without loss of catalytic activity. New protocol was developed for synthesis of Quinazolinones by condensation of anthranilamide with different aldehydes catalysed by rare earth metal oxide namely Gd2MoO6 doped on ZnO. The catalyst was synthesised by hydrothermal method. The catalyst exhibits excellent catalytic activity and was used to synthesis of various quinazoline derivatives. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, we explored novel CeZrO4−δ as a catalyst for Knoevenagel condensation of aldehydes with reactive methylene compounds like malononitrile and ethylcyanoacetate. For the present study, ceria, zirconia and CeZrO4−δ were prepared by gel combustion method and well characterized using XRD, SEM, EDX, BET and TPD analyses, etc. A wide range of aldehydes were effectively condensed over novel CeZrO4−δ with reactive methylene compounds with high yields. In addition, the CeZrO4−δ was effectively reused for five consecutive cycles without significant loss in its activity. To the best of our knowledge, this is the first liquid-phase application of pure CeZrO4−δ.Graphical abstract: [ABSTRACT FROM AUTHOR]