Synthesis of Aromatic Dibenzyl Disulfideusing H2S and Solid Reusable Resin as Catalys

Abstract

During hydro desulfurization or hydrotreatment of crude oil in petroleum refineries, one or more gaseous by products are produced with hydrogen sulfide (H2S) infused into it. Since the presence of H2S, corrodes the process equipment and is highly toxic, it is eliminated from the gas stream and transformed into harmless forms. H2S from gas stream is removed using amine treating unit and is treated in the Claus unit for the production of elemental sulfur. But in Claus process valuable hydrogen energy is lost and requires exact process control over ratio of oxygen to hydrogen sulfide feed. Therefore, an alternative process i.e. Phase Transfer Catalysis which could transform H2S to valuable chemicals is greatly welcome in the process industry. The valuable chemical such as Dibenzyl disulfide (DBDS) find their application in manufacturing corrosion inhibitors, fragrance compounds, high pressure lubricant additives and other organic compounds. This work was carried out to study the synthesis of fine chemicals like Dibenzyl Disulfide (DBDS) and using H2S-rich monoethanolamine (MEA) and benzyl chloride (BC) under Liquid-Liquid-Solid phase transfer catalysis with a tri-phase catalyst. Owing to its solid state, availability, cost and reusability, Amberlite IR 400 is selected as a PTC. A parametric study was carried out which emphasized upon the impact of catalyst loading as one of the process variables on the conversion of benzyl chloride and selectivity of DBDS and parametric study with these substances revealed 100 % selectivity for desired product at ambient condition. The effects are utilized to establish a suitable mechanism of the reaction to explain the course of the reaction. The overall objective of this study is to maximize conversion of reactant BC and selectivity of DBDS.