汽油纤维液膜脱硫醇工艺中硫化物氧化反应的研究

采用连续抽提-氧化过程模拟汽油纤维液膜脱硫醇工艺,研究了汽油纤维液膜脱硫醇过程中硫化氢中的硫离子(S2-)和硫醇中的硫醇离子(C3H7S-)的转化率规律及S2-氧化产物的分布情况;通过汽油铜片腐蚀实验考察了催化剂碱液氧化再生过程中生成的单质S对汽油腐蚀性能的影响,并对S2-深度氧化条件进行了探讨。实验结果表明,S2-的转化率随抽提-氧化次数的增加和汽油中C3H7S-含量的增加而降低,C3H7S-的转化率随抽提-氧化次数的增加而降低;在四磺化酞菁钴含量为100μg/g、w(NaOH)=10%、抽提温度30℃、抽提时间20m in、氧化温度30℃、氧化时间20m in、搅拌转速1 200r/m in、空气流量56mL/m in的条件下,S2-的主要氧化产物为单质S和S2O32-;催化剂碱液中的部分单质S会溶解在汽油中,造成汽油的铜片腐蚀程度加剧;在抽提-氧化过程中,升高氧化温度、延长氧化时间,有利于S2-深度氧化为S2O32-。

Sulfide Oxidation in Fiber-Liquid Membrane Demercaptanizing Process for Gasoline

Successive extraction-oxidation was adopted to simulate fiber-liquid membrane demercaptanizing process of gasoline for studying conversion of S2-in hydrogen sulfide and C3H7S-in mercaptan in the process.The distribution of S2-oxidation products in the process was also investigated.Effect of sulfur produced by oxidation of catalyst caustic solution on corrosive property of gasoline was investigated by gasoline copper corrosion test.The deep oxidation conditions of S2-were discussed.S2-conversion lowers either with increase of extraction-oxidation cycles or with increase of mercaptan content in gasoline.Conversion of C3H7S-also lowers with increase of extraction-oxidation cycles.When cobalt tetrasulfonate phthalocyanine content 100 μg/g,w(NaOH) 10%,extraction temperature 30 ℃,extraction time 20 min,oxidation temperature 30 ℃,oxidation time 20 min,stir speed 1 200 r/min,air flow rate 56 mL/min,main products of S2-oxidation are sulfur and S2O2-3,and content of the latter is less than the former.Sulfur in catalyst caustic solution then dissolves in gasoline drawn for next extraction,which aggravates copper corrosion level of gasoline.Higher oxidation temperature and longer oxidation time are favorable to oxidation process of S2-into S2O2-3.