Study On C5 Desulfurization Technology By Solvent Extraction

C5 is a type of byproduct which comes from oil hydrocarbon pyrolysis in the process of high temperature produces. C5 contains more than 20 kinds of ingredients complex compounds and isoprene is one of them with a high content as an important organic chemical raw materials. The useful chemical raw materials is isolate from carbon five separation process for the application in the downstream products. It has become an important approach to make full use of the petroleum resources and improve economic efficiency of ethylene production. But in the separation process, the product of isoprene contains 30--50 ppm of sulfide, which is mixed by carbon disulfide mainly with 90% of the total sulfur content. The existence of sulfur-containing compounds seriously affect the application of isoprene in the downstream products. Hence, a new effective desulfurization method has become an urgent need.Now, the world oil resources is gradually depleted and heavy crude production is gradually improved, which results in a higher sulfide content in by-product of C5. The traditional hydride sulfurization technology can remove most of sulfide, but it is difficult to reach the deep desulfurization. Due to the shortage of deep hydrogenation desulfurization technology, extraction desulfurization technology has attracted attention from the researchers about technical advantages, research progress, industrial applications and so on.The research of this paper is focused on extraction agents, which can remove sulfide to depart from the isoprene effectively and reach the purpose of deep desulfurization.In the experiment, we investigates the different extraction agents and finds out a cheap extraction agent system, then the conditions of desulfurization process is also optimized.Results show that extraction agent system of using DMF, ethylene glycol or methanol respectively with alkaline solution have the higher desulfurization effect In the reaction conditions of temperature 25℃, reaction time 40 min, the volume ratio 1:2:1 of isoprene,extraction agent and alkali solution, the total sulfur content of isoprene can be decreased to3 ppm from 30-50 ppm.