Extending the Duration of Inter-Washing Cycles of a Multi-Tube Reactor for Linear Alkylbenzenes Sulfonation.

In this work, we analyze the influence of the linear alkylbenzenes consumption of in a multitube film sulfonation reactor on the formation of viscous by-products, tetralins and sulfones, using the method of mathematical modeling. It was found that an increase in the consumption of raw materials from 3500 to 4500 kg/hour at a constant molar ratio of SO3/LAB equal to 1.08 makes it possible to achieve a decrease in the contact time of linear alkylbenzene with a sulfonating agent from 30.1 to 25.4 seconds and an increase in the duration of inter-flushing cycles due to a decrease in the viscosity of the organic liquid film and the normalization of the hydrodynamic regime of the flow of raw materials. It was also determined that the duration of inter-flushing cycles is influenced by the content of light aromatic hydrocarbons in the sulphonated raw material. An increase in the content of aromatic hydrocarbons leads to a decrease in the duration of the inter-flush cycles. This is due to the fact that light aromatic hydrocarbons are the source of the formation of viscous by-products - tetralins, which have a negative effect on the hydrodynamic regime of the liquid film flow. Calculations using a mathematical model showed that with an aromatic hydrocarbon content in the feed of 2 %wt. the duration of the inter-washing cycle at a standard flow rate of 3500 kg/hour is 15 days, and at 6 % wt. - 10 days. At the same time, an increase in consumption up to 4500 kg/hour makes it possible to achieve a cycle time at 2% wt. up to 17 days, and at 6% wt. up to 16 days. [ABSTRACT FROM AUTHOR]