Mathematical analysis of physicochemical phenomena in the catalyst during hydrogenating depolymerization of coal extract benzene insoluble fraction

doi:10.1016/j.cjche.2014.08.008

摘要/Abstract

摘要： Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al₂O₃ catalystwere assessed using a mathematical model. The analytical equations of the mathematical modelwere generated based onmaterial balance incorporating the physico-chemical phenomena (reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radii of the catalyst's pores to enable free transport of reactants in the grain interior.

关键词: Coal extract, Benzene insolubles, Catalyst, Depolymerization, Kinetics

Abstract: Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co-Mo/Al₂O₃ catalystwere assessed using a mathematical model. The analytical equations of the mathematical modelwere generated based onmaterial balance incorporating the physico-chemical phenomena (reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radii of the catalyst's pores to enable free transport of reactants in the grain interior.

Key words: Coal extract, Benzene insolubles, Catalyst, Depolymerization, Kinetics

Jerzy Szczygieł, Marek Stolarski. Mathematical analysis of physicochemical phenomena in the catalyst during hydrogenating depolymerization of coal extract benzene insoluble fraction[J]. Chinese Journal of Chemical Engineering, 2015, 23(6): 962-973.

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