АКТИВНОСТЬ НИКЕЛЬ-МОЛИБДЕНОВОГО КАТАЛИЗАТОРА, РЕГЕНЕРИРОВАННОГО МЕТОДОМ СВЕРХКРИТИЧЕСКОЙ ФЛЮИДНОЙ ЭКСТРАКЦИИ

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The activity of selective hydrogenation catalyst samples after supercritical fluid extraction regeneration at a temperature of 473 K and a pressure of 20 MPa with pure supercritical carbon dioxide and modified with hexane and ethanol was evaluated. The selectivity and chemical activity of the nickel-molybdenum catalyst LD-145 was determined on a model substance by the rate of the chemical reaction of hydrodesulfurization of the substance with the formation of dibenzotifene and the hydrogenation reaction of the substance with the formation of naphthalene in a flow-through experimental setup. The qualitative composition of the hydronisate was determined by gas-liquid chromatography on a Kristall-2000 chromatograph. The activity in the target reaction of naphthalene hydrogenation of the deactivated catalyst was 41.3%; catalyst regenerated with pure supercritical carbon dioxide - 43.4%; sample regenerated with a mixture of supercritical carbon dioxide + ethanol - 45.5%; and the sample regenerated with a mixture of supercritical carbon dioxide + hexane - 57%. Thus, the highest hydrogenation capacity was achieved on the sample regenerated with modified supercritical carbon dioxide hexane. Thus, the test results indicate an increase in the catalytic activity of catalyst samples that were regenerated by the supercritical fluid extraction method. It has been established that both the hydrogenating and hydrodesulfurizing functions of the catalyst can be restored. The level of recovery of the target hydrogenating activity of the catalyst achieved in this work is 57%. The level of recovery of catalytic activity of the spent catalyst samples can be improved by optimizing the conditions of supercritical fluid extraction process, more successful selection of the physical and chemical nature of the extractant and possibly earlier abandonment of the method of oxidative regeneration of the investigated catalyst during its operation.