PEG对Ni-Mo-W非负载型催化剂加氢脱硫性能的改进研究

Hydrodesulfurization performance of Ni-Mo-W unsupported catalysts improved by PEG

非负载型催化剂近年来已逐渐成为石油馏分加氢精制催化剂的研究热点,然而对其研究还远不够深入,金属分散性差、利用率低限制了其实际应用。在Ni-Mo-W非负载型催化剂制备过程中引入助剂聚乙二醇(PEG),采用XRD、N_2物理吸脱附、NH_3-TPD和SEM等手段对催化剂的织构性质、酸性和微观形貌进行表征。结果表明,以PEG为助剂制备的催化剂金属分散性更好,孔隙结构发达,具有更大的酸量和良好的微观形貌,加氢脱硫(HDS)活性显著提升。PEG对催化剂HDS性能的改进程度随PEG分子量的增大而降低,当PEG分子量为400时,Ni-Mo-W非负载型催化剂具有最佳的HDS性能,对FCC柴油的脱硫率可达99.8%,加氢柴油硫含量仅为11μg/g。

Unsupported catalysts have become a research focus of petroleum refining catalysts in recent years, however, the related research is still far from enough, poor metal dispersion and low metal utilization ratio of unsupported catalysts severely influencing their practical application. In this paper, polyethylene glycol （PEG） was introduced as additive in the preparation process to prepare the Ni-Mo-W unsupported catalysts and the textural properties, acidity and microstructure of catalysts were characterized by N2 adsorption, NH3-TPD and SEM. The results showed that the catalysts prepared with PEG had better metal dispersion, developed pore structure, greater acidity and higher HDS rates. The influence of PEG on HDS performance of unsupported catalysts decreased with the increase of PEG molecular weight. The catalyst with PEG400 had the best HDS performance, and the desulfurization rates of FCC diesel could be up to 99.8%, and the sulfur content of hydrogenation diesel was only 11μg/g.