Modeling the multistage process of the linear alkylbenzene sulfonic acid manufacturing

摘要

Linear alkylbenzene sulfonic acid (ASA) is used to produce industrial and domestic synthetic detergents and is obtained via a multistage technology. Unsteady mathematical models were developed for all technological stages. With use of the developed models we studied how the modes in the dehydrogenation reactor influence the product quality and yield. It was found that increase in the hydrogen/feedstock ratio in the dehydrogenation reactor from 6 to 8 mol/mol decreases the outlet dienes concentration from 0.57 to 0.46%wt. This reduces the amount of heavy aromatic compounds (HAR) formed in the alkylation reactor, as well as the optimal flow rate of alkylation HF catalyst to regeneration from 4.5 to 4.1 m(3)/h. The decrease of the hydrogen/feedstock ratio in the dehydrogenation reactor from 6.5 to 6 mol/mol intensifies the highly viscous component accumulation in the sulfonation reactor, reducing the period between the reactor washings from 13 to 10 days. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.