【作者】 吕宏缨；

【导师】 李灿；

【作者基本信息】 中国科学院研究生院（大连化学物理研究所） ， 物理化学， 2007， 博士

【摘要】 为了减少环境污染,世界各国对燃料油中的硫含量进行了日益严格的法规限制,要求生产和使用更加环境友好的超低硫汽油和柴油。氧化脱硫由于反应条件温和,不使用昂贵的氢源,对油品中具有空间位阻的含硫化合物（如4,6-二甲基二苯并噻吩）有较高的氧化活性等,被认为是很有应用前景的一种脱硫技术,受到学术界和工业界的广泛关注。本论文工作研究了乳液体系中含硫分子的氧化脱硫过程。用过氧化氢为氧源,在温和条件下,利用双亲性催化剂Q₄[H₂NaPW₁₀O₃₆],将催化剂组装在乳液液滴界面,将含硫化合物（包括苯并噻吩,二苯并噻吩及其衍生物）在乳液（水/油）氧化体系中氧化和萃取。该乳液体系由催化剂,模型或真实柴油以及过氧化氢水溶液组成（W/O）。发现催化剂[C₁₈H₃₇N（CH₃）₃]_4-[H₂NaPW₁₀O₃₆]在油包水体系中对于模型柴油和真实油品中的含硫化合物具有极高的催化氧化活性,能以接近化学计量比的过氧化氢（O/S≤3）氧化剂,将含硫化合物几乎全部氧化成相应的砜。实验结果表明,含硫化合物的氧化活性顺序如下: 4,6-二甲基苯并噻吩>二苯并噻吩>5-甲基苯并噻吩>苯并噻吩。生成的砜可以通过萃取从柴油中分离。通过氧化萃取过程,加氢柴油的硫含量从500 ppm降至0.1 ppm,同时,直馏柴油的硫含量从6000 ppm降至30 ppm,优于目前的欧Ⅲ标准。此外,还研究了乳液体系中用氧气为氧源,醛为共氧化剂,在双亲性催化剂[C₁₈H₃₇N（CH₃）₃]₅[PV₂Mo₁₀O₄₀]作用下,二苯并噻吩的氧化过程。研究发现,二苯并噻吩能在温和条件下被氧化为相应的亚砜和砜,为将来空气氧为氧源进行油品的氧化脱硫提供了一个新的思路和可能。更多还原

【Abstract】 In the last decade, much attention has been paid to the deep desulfurization of fuel oils due to more stringent environmental regulations. Oxidative desulfurization（ODS） combined with extraction is considered to be one of the most promising processes and the refractory compounds, such as, 4, 6-dimethyldibenzothiophens can be oxidized relatively easily under mild reaction conditions.The oxidation of sulfur-containing compounds （benzothiophene, dibenzothiophene and their derivatives） in diesel was conducted in emulsion oxidative system （water in oil, W/O） composed of diesel, 30 wt% hydrogen peroxide and an amphiphilic catalyst [C₁₈H₃₇N（CH₃）₃]₄[H₂NaPW₁₀O₃₆] under mild conditions. The catalyst [C₁₈H₃₇N（CH₃）₃]4[H₂NaPW₁₀O₃₆] in the W/O emulsion system demonstrates very high catalytic activity that all sulfur-containing compounds in either model or actual diesel were selectively oxidized into their corresponding sulfones using nearly a stoichiometric amount of hydrogen peroxide as an oxidant. The catalytic oxidation reactivity of sulfur containing compounds was found to be in the following order: 4,6-dimethyldibenzothiophene > dibenzothiophene > 5-mthylbenzothiophene > benzothiophene. Although benzothiophene was relatively difficult to be oxidized, it can be also efficiently oxidized into sulfone in the emulsion system. The oxidized products, sulfones were readily separated from diesel using an extractionprocess. The sulfur level of a pre-hydrotreated diesel was lowered from 500 ppm to 0.1 ppm, while the sulfur level of a straight-run diesel was decreased from 6000 ppm to 30 ppm, using oxidation-extraction in emulsion system.In addition, the oxidation of dibenzothiophene （DBT） with molecular oxygen in the emulsion oxidative system （acetonitrile in decalin, W/O） was conducted by using polyoxometalate anion [C₁₈H₃₈N（CH₃）₃]₅[PV₂Mo₁₀O₄₀ and aldehyde as catalyst and sacrificial material under mild condition. It was found that the dibenzothiophene can be oxidized to corresponding sulfoxide and sulfone in the emulsion system under mild conditions. This possibly opens a new route for ultra-deep desulfurization of diesel using molecular oxygen as the oxidant.更多还原