Abstract: The control index of sulfides content in gasoline additive MTBE was introduced based on the National 5th Stage Motor Vehicle Gasoline Standard. A new algorithm for enrichment coefficient calculation was given based on the analysis of sulfides composition， sources and enrichment effect in MTBE. The results showed that enrichment coefficient was up to 4.44 at ethylene content in LPG between 15%～30% by weight. The analysis of other influencing factors showed that enrichment effect was the most important factor. As the investigation of MTBE desulfurization process by distillation and LPG fine desulfurization process demonstrated that two-column MTBE desulfurization process by distillation was more suitable in new gasoline additive production，considering its relatively low invest cost，energy cost and use of adsorbent，and the sulfides content in MTBE can be controlled under 3mg/kg.

Key words: LPG, MTBE, distillation, enrichment effect, deep desulfurization

摘要： 根据国家第五阶段车用汽油标准对汽油硫含量的要求，提出了满足该标准的汽油添加剂甲基叔丁基醚（MTBE）中硫含量的控制指标。分析了MTBE中硫化物的组成、来源及富集效应产生的原因，提出了富集系数的准确的计算方法。计算结果表明，当原料液化气中异丁烯质量分数为15%～30%时，富集系数最高可达4.44。在比较其他引起MTBE中硫含量升高因素的基础上，认为富集效应是导致其含硫量较原料液化气大幅升高以致超标的重要原因。同时研究了液化石油气精脱硫及MTBE蒸馏脱硫两种深度脱硫工艺，通过全面对比分析，认为MTBE双塔脱硫工艺在设备投资、能耗、吸附剂使用等方面均具有优势，并且可以将MTBE中的硫含量稳定地控制在3mg/kg以下。低于10mg/kg的控制指标要求，更适合于国家第五阶段车用汽油标准的添加剂的生产。

关键词: 液化石油气, 甲基叔丁基醚, 蒸馏, 富集效应, 深度脱硫