Wavelet method to film-pore diffusion model for methylene blue adsorption onto plant leaf powders

In this paper, we have developed an accurate and efficient Haar wavelet method to solve film-pore diffusion model. Film-pore diffusion model is widely used to determine study the kinetics of adsorption systems. To the best of our knowledge, until now rigorous wavelet solution has been not reported for solving film-pore diffusion model. The use of Haar wavelets is found to be accurate, simple, fast, flexible, convenient, and computationally attractive. The power of the manageable method is confirmed. It is shown that film-pore diffusion model satisfactorily describes the kinetics of methylene blue adsorption onto three low-cost adsorbents, Gauva, teak and gulmohar plant leaf powders, used in this study.     

Green synthesis of carbon solid acid catalysts using methane sulfonic acid and its application in the conversion of cellulose to platform chemicals

Cellulose - Levulinic acid (LA) is an important platform chemical and used for the production of various biofuels and bio-based chemicals. Formic acid (FA) is a major product of biomass conversion...     

Synthesis of SBA-15 from low cost silica precursor obtained from sugarcane leaf ash and its application as a support matrix for lipase in biodiesel production

Ordered mesoporous silica material was synthesized from a low-cost precursor, sugarcane leaf ash, was used as a support matrix for lipase for the production of biodiesel. The mesoporous samples were characterized using Fourier transform infra red spectroscopy. The surface topography and morphology of the mesoporous materials were studied using scanning electron microscope. The pore diameter, pore volume, Brunauer Emmett and Teller surface area of the mesoporous material were determined by N₂ gas adsorption technique. Different pore size Santa Barbara Acid-15 (SBA-15) samples were synthesized and their lipase immobilization capacity and specific enzyme activity of immobilization lipase were determined and compared. Lipase from Candida Antarctica immobilized on SBA-15 (C) had shown maximum percentage immobilization and specific enzyme activity. The immobilized lipase mesoporous matrix was used for biodiesel production from crude non-edible Calophyllum inophyllum oil. The percentage yield of fatty acid methyl ester, 97.6 % was obtained under optimized conditions: 100 mg of lipase immobilized on SBA-15, 6:1 methanol to oil molar ratio, the reaction of 2 g C. inophyllum oil with methanol.     

Enzyme mediated synthesis of Ag–TiO2 photocatalyst for visible light degradation of reactive dye from aqueous solution

The purpose of this study was to develop bio-inspired photocatalyst with solar light activity for textile dye degradation. Three TiO₂ samples namely TiO₂ (TiO₂-A), biotemplated TiO₂ (TiO₂-B), and enzyme mediated Ag–TiO₂ biotemplate (TiO₂-C), were developed. The presence of anatase phase of TiO₂ and silver in synthesized samples were confirmed using X-ray diffraction, field emission scanning electron microscopy, energy-dispersive spectroscopy, and UV–Vis–NIR spectroscopy. Photocatalytic efficiencies of these photocatalysts were evaluated by studying the oxidation of a commercial reactive dye (reactive black) under solar light irradiation in batch reactors. Photocatalytic efficiencies of the sample were compared using statistical tools like one-way ANOVA and Tukey test. The results confirmed that photocatalytic efficiency of TiO₂-C was 40 % higher than that of TiO₂-A under solar light irradiation.