To acquire a deeper understanding of surface chemistry of fly ash along with thermal activation, the states of mineral phases, water and -OH groups on silica are studied in fly ash at different calcination temperatures by DR/FTIR spectroscopic technique. DR/FTIR spectroscopy allows differentiation of various types of bonds in a material on a molecular level. The spectroscopic results are also supported by XRF, XRD and SEM analysis. Studied fly ash was collected from Jamshedpur Thermal Power Station as an extremely fine ash, formed from the inorganic components of the coal, mainly silica and alumina which remain after combustion of the carbonaceous part of the coal. Distinguish changes were observed in fly ash IR bands regarding absorbed water, -OH group and Si-O-Si group with thermal activation. This investigation reveals that as the temperature increases, the physically adsorbed water begins to remove first, then silanol groups on surface is dehydrated. Increased temperature causes formation of different crystalline phases like quartz, mullite and hematite etc. and increased the crystallinity of the calcined samples.

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Potentially active and eco-friendly solid acid catalysts have been synthesized by loading different weight percentages (10, 15, and 50) of nickel oxide on thermally activated Turkish perlite through the deposition-precipitation method. Structural features of prepared catalysts were analyzed using BET surface area analysis, X-ray diffraction, SEM, SEM-EDX, TEM, FT-IR, pyridine adsorbed FT-IR, UV-Vis DRS, and TGA techniques. Pyridine adsorbed FT-IR analysis confirmed the presence of the optimum amount of Bronsted acidic sites in a catalyst having 15 wt. % loading of nickel oxide which was tested for catalyzing a series of Claisen-Schmidt condensation of cyclohexanone and aromatic aldehydes to produce good isolated yield (90-93%) of 2,6bis(substituted benzylidene)cyclohexanones, significantly used in anti-tumor and cytotoxic activities. The high catalytic efficiency of the chosen catalyst remains almost 2 intact up to six reaction cycles. On higher wt. % loading of nickel oxide, crystallite size increases along with agglomeration of larger nickel oxide particles on catalyst surface resulting in pore blockage and poor catalytic activity. Loading of NiO on the surface of thermally activated Turkish perlite was confirmed by SEM-EDX analysis and TEM observations show that the particle size of the preferred catalyst was less than 50 nm.Based on results drawn from XRD, FT-IR, pyridine adsorbed FT-IR, UV-Vis DRS studies, model structures were proposed for Turkish perlite and all prepared catalysts.During this work, the catalytic potential of the preferred catalyst was compared with other previously reported catalysts and it showed appreciable results. The formed products were further confirmed by their melting point and 1 H-NMR analysis.