二乙基多硫醚混合硫化剂的合成及反应机理研究

摘要

Diethyl polysulfides as mixed sulfiding agent were synthesized by using industrial sulfur from refining enterprises ,sodium sulfide and bromoethane in the presence of phase transfer catalyst tetrabutylammonium bromide .The influences of reaction conditions on sulfur content were studied and the synthesis reaction mechanisms were discussed .The results showed that the ring‐opening of S8 molecules was the key step of the synthesis reaction and the addition of sodium sulphide greatly re‐duced the activation temperature of S8 .When the molar ratio of S to Na2 S was 4∶1 ,the first step re‐action temperature was 50 ℃ ,the first step reaction time was 25 minutes ,the second step reaction temperature was room temperature ,the second step reaction time was 1 .5 hours and the TBAB molar fraction was 4% ,the mass fraction of sulfur in diethyl polysulfides reached 63 .86% ,the flash point was 83 .5 ℃ and the oil solubility was good .The reaction has advantages of wide raw material sources , simple synthetic route ,mild reaction conditions and environmental friendliness ,w hich has a good de‐velopment and application prospects .%以直接来源于炼油企业的工业硫磺和硫化钠、溴乙烷为原料，在相转移催化剂四丁基溴化铵的作用下合成二乙基多硫醚混合硫化剂，对影响产物硫含量的反应条件进行了研究，并对合成反应机理进行了探讨。结果表明，S8分子的开环是合成反应的关键步骤，硫化钠的加入大大降低了S8的活化温度；在 n（S ）∶ n（N a2 S ）为4∶1、一步反应温度为50℃、一步反应时间为25 m in、二步反应温度为室温、二步反应时间为1．5h、四丁基溴化铵摩尔分数为4％的条件下合成的二乙基多硫醚，硫质量分数达63．86％，闪点为83．5℃，油溶性好。该反应原料来源广泛，合成路线简单，反应条件温和且环境友好，具有良好的开发应用前景。