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Information × Registration Number 0221U000144, 0117U000101 , R & D reports Title Metal/zeolite catalysts of carbonium ion transformation of hydrocarbons. popup.stage_title Head Patrylak Lyubov K., Доктор хімічних наук Registration Date 02-01-2021 Organization V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry of the National Academy of Sciences of Ukraine popup.description2  It was established the advantage of microporous catalysts in n-hexane isomerization, basing on the results of study of Ni and/or Pd-containing bifunctional catalysts based on microporous zeolites HMOR, HMFI and micromesoporous zeolites HBEA, HMFI, HMOR. Adequacy of the n-hexane isomerization mechanism proposed for Pd-catalysts has been confirmed for Ni-containing objects. It is postulated that Ni, in contrast to Pd, significantly increases the acidity of the Bronsted sites of zeolites. This results in a decrease in the temperature of the isomerization reaction. It was found for bimetallic Ni/Pd MFI isomerization catalysts that the role of Ni is to reduce the temperature of the beginning of transformations, while the role of Pd is to intensify them. It was shown that not Ni but Pd-containing nonacid mesoporous carbon is active in the conversion of n-hexane. The course of aromatization was explained by the implementation of the mechanism of direct dehydrocyclization of hexane on palladium agglomerates which are more massive than those for Ni case, and the course of isomerization and cracking reactions – by incomplete reduction of Pd2+ ions on the carbon surface, leading to LAS and BAS generating. Ni-containing HMFI catalyst was obtained with the efficiency close to Pd-containing one (1%wt.), as well as Pd-containing catalyst with half the metal content which maintains at 275-300 °C the yield of isomers of 50%wt at the selectivity > 95%. It was achieved on a bimetallic catalyst with an optimal metal content(0.5%wt of each)at 250°C under micropulse testing conditions the high yield of hexane isomers(42%wt) at selectivity>90%, which exceeds the characteristics of monometallic samples at a given temperature. In the case of Pd-modification of zeolite samples, an extreme dependence of the catalyst activity in the isomerization of n-hexane on the size of metal nanoparticles with a maximum in the region of 10-15 nm was found, regardless of the method of introduction of Pd. Product Description popup.authors Burlachenko Kateryna O. Voloshyna Yuliya G. Zlochevskyi Kostiantyn V. Zubenko Stepan О. Konovalov Serhiy V. Pertko Oleksandra P. Yakovenko Angela V. popup.nrat_date 2021-01-02 Close