[2009年10月31日]

柴油超深度加氢脱硫研究取得新进展

随着全球范围内对于环境保护的持续关注,有关环境治理的课题就成为当今世界的研究热点,燃料油中含硫化合物的脱除问题就是其中之一。继我组首创性的报道了利用乳液催化方法,对柴油进行超深度氧化脱硫之后(李灿,蒋宗轩,高金波,吕宏缨等人,Chem. Eur. J. 2004,10, 2277 – 2280; Journal of Catalysis 239, 2006, 369–375; Chem. Commun., 2007, 150–152; Chem. Commun., 2008, 332–334),近期,我组又在柴油的超深度加氢脱硫领域取得了令人瞩目的进展。王璐等人设计合成了具有特殊结构的多金属本体加氢脱硫催化剂,首创性的将具有层状结构的Ni物种作为载体引入催化剂当中,从而提高了活性金属之间分散以及接触的程度,得到了具有高加氢脱硫活性的复合物种。通过对于模型含硫化合物以及真实柴油的加氢脱硫反应评价之后,发现此种催化剂具有较高的本征加氢脱硫活性,并且表观反应活性达到了商业催化剂活性的7.5倍,在现有的工业操作条件下,可以实现对于柴油的超深度脱硫,具有非常好的工业应用前景。通过对于催化剂的进一步表征工作,作者等人发现了此种催化剂独特的层状结构以及某些复合金属活性相的存在,从而解释了催化剂具有高活性的原因。此项工作的意义不仅在于为我们提供了一种通过多金属化、无载体化改进加氢脱硫催化剂活性的新思路,还在于明确的为我们提出了合成催化剂的机理,此机理对于今后催化剂的设计合成具有理论指导价值。文章做为communication发表在近期出版的Chemistry - A European Journal上(Ultra-Deep Hydrodesulfurization of Diesel Fuels on Trimetallic NiMoW Sulfide Catalysts, Lu Wang, Yongna Zhang, Yuliang Zhang, Zongxuan Jiang*, Can Li*, Published online on October 27, 2009. DOI: 10.1002/chem.200901997

Communication

Ultra-Deep Hydrodesulfurization of Diesel Fuels on Trimetallic NiMoW Sulfide Catalysts

Lu Wang, Yongna Zhang, Yuliang Zhang, Zongxuan Jiang*, Can Li* 

Published online on October 27, 2009.  DOI: 10.1002/chem.200901997 

Keywords: Ultra-deep Hydrodesulfurization 4,6-dimethyldibenzothiophene (4,6-DMDBT) Diesel NiMoW Sulfide Catalyst

Abstract

Developing ultra-deep hydrodesulfurization (HDS) catalysts with super high activity has been one of the most challenging and important subjects because increasingly stringent environmental regulations for the sulfur content in diesel fuels have been enacted throughout the world. A novel tri-metallic NiMoW catalyst was prepared by a surfactant-assisted co-precipitation method using hydrotalcite-like basic nickel carbonate as the nickel source. The NiMoW-3 exhibits much higher overall rate constant than the CoNiMoW/Al2O3 commercial catalysts for the HDS of 4,6-DMDBT and the apparent activation energy correspondingly decreases from 176 kJ•mol-1 to 140 kJ•mol-1. In the HDS of actual diesel, the sulfur content could be lowered from about 1400 ppm to less than 1 ppm. The characterization results show that the NiMoW sulfide catalyst has unique multi-layered structure, in which the Ni7S6 with layered structure acts as a support and Mo, W or MoW sulfide particles are deposited on the surface and interlayer galleries of the Ni7S6 support. It is proposed that Mo-W-S species deposited on Ni7S6 support may generate the highly active sites for the HDS.