催化氧化去除油品中二苯并噻吩的研究

发布时间：2018-09-02 06:26

【摘要】：氧化脱硫(Oxidative desulfurization ODS)是一种有效的石油脱硫工艺。但是该工艺中所需的催化剂存在制备耗能大,水溶性氧化剂无法与硫化物完全反应的缺点。本研究将采用浸渍法制备新型催化剂,添加溶油性氧化剂,解决了氧化脱硫中的两大缺陷,同时对催化剂制备条件、表征、反应条件、重复使用性、反应动力学、机理等方面进行详细研究。该催化剂能将硫含量从400 mg?kg-1降到3.52mg?kg-1,且能重复使用7次。本研究采用浸渍法将钨负载在丙烯酸系弱酸性阳离子交换树脂D152上,制成了催化剂W/D152。实验研究了浸渍钨溶液p H值、温度、浓度等制备条件对催化氧化去除二苯并噻吩(DBT)活性的影响,并确定了催化剂最佳制备条件。运用红外光谱(FTIR)和环境电镜扫描(SEM)对W/D152的微观面貌进行了观察和分析。结果表明,在p H值为2.5,温度为30℃,质量体积浓度为2.5%的含钨溶液条件下制备的催化剂脱硫效果最佳;初始溶液含硫浓度为400 mg?kg-1,最高去除率达到99.1%,处理后的样品含硫量约3.52 mg?kg-1,达到了总含硫量要求小于10 mg?kg-1的欧五标准。对新制备的催化剂进行表征。采用环境电镜扫描(SEM)和红外。催化剂表征结果表明,钨成功负载在树脂上,并形成一层薄层。以二苯并噻吩为目标处理物,以过氧化环己酮(CYHPO)为氧化剂分别对反应温度、反应时间、氧化剂用量、催化剂用量四个反应因素进行考察,选择最佳催化氧化条件。实验结果表明:在反应温度为100℃、反应时间为40min,模拟油与催化剂的质量比为100,氧化剂与含硫量摩尔比为2.5时,反应条件最佳。在最佳反应条件下,将初始含硫量为400 mg?kg-1减低到含硫量约3.52 mg?kg-1,最高去除率达到99.1%。催化剂的重复使用次数是衡量一种催化剂可靠性的一个重要指标。在相同反应条件下,重复使用该催化剂,实验结果表明:该催化剂循环使用7次后,仍可达到欧五标准,具备良好的重复使用效能。对本实验的反应动力学进行模拟,模拟结果表明:该催化剂催化氧化二苯并噻吩的反应符合一级动力学模型,速率常数为0.1091 min-1,对比没添加催化剂的反应动力学,反应时间达到40 min后,脱硫率只有45.3%。此外,本催化氧化的反应机理也进行了研究。采用真实汽油对新制备的催化剂进行脱硫效果验证。实验结果表明:该催化剂在于模拟实验相同反应条件下,脱硫率为97%,具备一定的工业使用价值。
[Abstract]:Oxidative desulfurization (Oxidative desulfurization ODS) is an effective process for petroleum desulfurization. However, the catalyst needed in this process has the disadvantages of high energy consumption and water soluble oxidants can not completely react with sulfides. In this study, a new type of catalyst was prepared by impregnation, and dissolved oxidant was added to solve the two major defects in oxidative desulfurization. At the same time, the preparation conditions, characterization, reaction conditions, reusability and kinetics of the catalyst were studied. The mechanism is studied in detail. The catalyst can reduce sulfur content from 400 mg?kg-1 to 3.52 mg / kg -1 and can be reused for 7 times. In this paper, W / D 152 catalyst was prepared by impregnating tungsten onto acrylic acid weak acid cation exchange resin D152. The effects of preparation conditions such as pH value, temperature and concentration of impregnated tungsten solution on the catalytic oxidation of dibenzothiophene (DBT) were studied and the optimum preparation conditions were determined. The microstructure of W/D152 was observed and analyzed by infrared (FTIR) and scanning (SEM). The results showed that the desulfurization effect of the catalyst was the best under the conditions of pH 2.5, temperature 30 鈩，

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