Abstract
The effect of coexistence of elemental sulfur, elemental sulfur/iron oxide and H2S was studied concerning with the formation of pentane, 2-pentene, polymerized compounds and sulfur-containing compounds in the hydrotreatment of 1-pentene. The hydrogenation of 1-pentene was promoted with H2S but suppressed with elemental sulfur. The isomerization was promoted with H2S and elemental sulfur. The formation of polymerized compounds was promoted with elemental sulfur but suppressed with H2S.
The sulfur-containing products consisted of three types of thiol (pentane-1-thiol, pentane-2-thiol and pentane-3-thiol) and four types of sulfide one of which was assigned dipentyl sulfide. In the reaction of 1-pentene with the existence of elemental sulfur, sulfides were the major products and thiols were rather minor products. With the raise of reaction temperature, the yields of sulfides decreased and the yields of thiols increased. In this reaction system, sulfides were considered to be the primary products and thiols were considered to be formed by cracking of sulfides.
In the reaction of 1-pentene with the existence of H2S, thiols were produced preferably to sulfides and both yields of thiols and sulfides increased with the raise of reaction temperature. In this reaction system, thiols were considered to be the primary products and sulfide were considered to be formed by further addition of 1-pentene to thiols.
In the reaction of 1-pentene with the existence of elemental sulfur/iron oxide, the yields of thiols increased with the amount of iron oxide, whereas the yields of sulfides decreased at 250°C but increased at 350°C with the amount of iron oxide. In the reaction at 350°C, H2S formed by the catalysis of iron oxide was considered to contribute to the production of sulfides.
