02179nas a2200265   4500008004100000022001400041245014500055210006900200260007400269300000900343490000800352520117700360653001501537653001801552653001901570653002101589653002801610100002201638700002101660700002801681700002501709700002601734700002401760856012901784       2013                        eng d  a0049-697900aEnhanced dual-effect of adsorption and photodegradation of SiO2 embedded TiO2 hybrid catalyst for improved decolourization of methylene blue0 aEnhanced dualeffect of adsorption and photodegradation of SiO2 e  aVAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDSbSPRINGERcSEP  a17260 v2243 a<p>Dual-effects of adsorption and photodegradation over titania, silica embedded titania, silica and commercial Degussa P-25 samples were studied for the decolourization of methylene blue in aqueous medium. Silica embedded titania and silica were prepared using inexpensive polymeric version of ethyl silicate as a source of silica. Catalysts were characterized by X-ray diffraction, scanning electron microscopy, UV-Vis spectroscopy and low temperature (77 K) nitrogen adsorption measurements. Among all the catalysts, silica embedded titania has exhibited faster decolourization of methylene blue solution on account of the enhancement of adsorption followed by degradation. An amount of the catalyst and the initial dye concentration of MB solution were found to influence the decolourization activity. Compared to titania catalyst, silica embedded titania and Degussa P-25 have shown the red shift in their UV-Vis spectrum. The experimental data of the reaction fitted well to the pseudo first order kinetic model. In present studies, the adsorption mechanism for the decolourization of MB solution was found to be applicable for an intra particle diffusion model.</p>10aAdsorption10akinetic model10aMethylene blue10aPhotodegradation10aSilica embedded titania1 aSonar, Shilpa, K.1 aWagh, Reshma, V.1 aNiphadkar, Prashant, S.1 aJoshi, Praphulla, N.1 aDeshpande, Shilpa, S.1 aAwate, Shobhana, V.  uhttps://library.ncl.res.in/content/enhanced-dual-effect-adsorption-and-photodegradation-sio2-embedded-tio2-hybrid-catalyst-002418nas a2200229   4500008004100000022001400041245013700055210006900192260006700261300001400328490000700342520151900349653002401868653001901892653002101911653001901932100002901951700002801980700002602008700002202034856013202056       2014                        eng d  a0268-257500aEsterification of renewable levulinic acid to ethyl levulinate biodiesel catalyzed by highly active and reusable desilicated H-ZSM-50 aEsterification of renewable levulinic acid to ethyl levulinate b  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcOCT  a1507-15150 v893 a<p>BACKGROUNDIn the near future, fossil fuel will have limitations in terms of availability and also great concerns over its environmental impact. New routes and related technologies based on renewable feedstocks can overcome most of these problems associated with fossil fuel. Among current biodiesel sources, ethyl levulinate (EL) biodiesel obtained from catalytic esterification of renewable levulinic acid (LA) with ethanol has received a great deal of attention. The use of desilicated H-ZSM-5 (DH-ZSM-5) as heterogeneous acid catalyst for EL biodiesel production in a closed system (under autogeneous pressure) was studied. RESULTSThe effect of reaction parameters such as ethanol to LA molar ratio (4:1 to 10:1), catalyst to LA ratio (0.10-0.25), speed of agitation (100-400rpm), particle size (53-355 mu m), reaction temperature (363-403K) and reaction time (7h) was investigated to maximize LA conversion. CONCLUSIONLevulinic acid conversion reached 95% over DH-ZSM-5 and the catalyst was reusable for up to six cycles. This LA conversion and the catalyst reusability values are higher than others reported in the literature. A pseudo-homogeneous (P-H) kinetic model indicated that reaction rate constants increased with increasing molar ratio, catalyst to LA ratio and reaction temperature. The activation energy decreased from 73.14 to 21.08 kJ mol(-1) when increasing the catalyst to LA ratio from 0.10 to 0.25, which implies a kinetically controlled reaction. (c) 2013 Society of Chemical Industry</p>10adesilicated H-ZSM-510aEsterification10aethyl levulinate10alevulinic acid1 aNandiwale, Kakasaheb, Y.1 aNiphadkar, Prashant, S.1 aDeshpande, Shilpa, S.1 aBokade, Vijay, V.  uhttps://library.ncl.res.in/content/esterification-renewable-levulinic-acid-ethyl-levulinate-biodiesel-catalyzed-highly-active-0