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Information × Registration Number 0219U000816, 0114U002198 , R & D reports Title Development of catalytic processes of the glycerin (biodiesel waste product) and its derivatives transformations into perspective products of the fine organic synthesis. popup.stage_title Head Kamalov G. L., Registration Date 27-02-2019 Organization A.V. Bogatsky, Physico-Chemical Institute of the National Academy of Sciences of Ukraine popup.description2 Influence of glycerol (GL) reaction conditions with acetone (Ac), benzaldehyde (BA) and physicochemical properties of H-modified samples of natural clinoptilolite (H-CLI), bentonite (H-Bent) and trepel (H-Tr) on their catalytic activity in comparison with sulphocathionite KU-2 was investigated. Research methods: experiment planning, potentiometry, spectrophotometry, volumetry, thin-layer (TLC) and gas-liquid (GLC) chromatography, IR, UV and NMR spectroscopy. It was found, that grinding time of H-Bent samples in mechanical agate mortar does not affect on their catalytic properties, but this factor is very important for H-CLI and H-Tr samples - the initial reaction rate increases in two fold, and GL conversion on 19% and 7%, respectively. With increase of Ac excess from 1,3 to 25, reaction rate passes over maximum, regardless of catalyst amount. For initial rates of this reaction: H-Bent> KU-2> H-CLI> H-Tr. The optimal conditions for obtaining H-CLI, H-Bent and H-Tr samples, affecting on their catalytic activity in GL reaction with BA, have been established. In other equal conditions, H-Bent samples are generally more active than H-CLI, H-Tr, and KU-2. At increase of catalyst amount to 10%, the following range of initial rates is observed: H-Bent> KU-2?H-CLI?H-Tr. The kinetics of GL reaction with FA in the presence of KU-2 and H-CLI, H-Bent and H-Tr samples was investigated. With increase of KU-2 amount, at GL excess, values of FA conversion are almost same. But initial rates of FA concentration decrease are less at ratio 10:1. At FA excess and simultaneous distillation of water azeotrope with benzene, a practically equimolar mixture of five (1) and six-membered (2) formals is formed with yield up to 80%. At FA double excess, yield of isomeric mixture 1 and 2 decreases, GL reacts exhaustively and mixture of bis-formals 1OCH2O1, 1OCH2O2 and 2OCH2O2 dominates. With increase of catalyst amount, FA conversion in the presence of H-CLI and H-Bent increases and reaches a constant value. In the case of Н-Тr, this dependence passes through maximum. H-Bent samples are more active than H-CLI and H-Tr, and the concentration reaction order according to FА in the presence of the first is equal to one. The kinetics of studied reactions are satisfactorily described by Michaelis-Menten model. Reaction mechanisms schemes are proposed. Product Description popup.authors Давтян Аракся Сейранівна Камалов Герберт Леонович Левченко Ольга Олександрівна Чіхічін Дмитро Герасимович Яволовський Аркадій Олександрович popup.nrat_date 2020-04-02 Close