Solvent free synthesis of Dibenzyl Sulfide using H2S rich Monoethanolamine under two phase transfer catalysis

Abstract

With the depletion of crude oil reserves, oil refineries are being forced to process sour crude which is high in sulfur content. Sulfur, if not removed from the system may corrode the system or may lead to unwanted side reactions which would entail consumption of reactants and energy. Usually the sulfur is removed by absorption in ammonia solution which is further processed in a Claus Unit to produce elemental sulfur which requires a high amount of energy. Also, the supply of elemental sulfur usually outstrips demand thereby eroding the profit margins. With a view to making more sophisticated fine chemicals which have higher usability and better market value, this project was undertaken to study the kinetics of the solvent-free synthesis of dibenzyl sulfide was carried out using H2S-rich monoethanolamine under two phase transfer catalysis with a phase transfer catalyst (PTC), polyethylene glycol (PEG). The effects of different parameters, such as speed of agitation, temperature, monoethanolamine concentration, catalyst concentration, initial sulfide concentration and concentration of benzyl chloride, on the conversion and reaction rate of benzyl chloride were studied to establish the mechanism of the reaction.