不同金属含量Ni-W催化剂的煤焦油加氢脱硫脱氮性能研究

Hydrodenitrogenation and hydrodesulfurization of coal tar on Ni-W catalysts with different metal loadings

以γ-Al_2O_3为载体,采用等体积浸渍法制备了五种金属原子比相同而金属负载量不同的Ni-W基催化剂。通过X射线衍射(XRD)、光电子能谱(XPS)、程序升温脱附(NH_3-TPD)、氮气吸附、高分辨透射电镜(HRTEM)等技术对催化剂进行了表征。在固定床反应器中,以中低温煤焦油为原料,考察了催化剂的加氢脱氮(HDN)和加氢脱硫(HDS)性能。结果表明,当Ni/W原子比为0.786时,负载金属后,催化剂的总酸量减少,且以中强酸为主。随着金属负载量的增加,催化剂的硫化程度逐渐增加,HDN活性先增加后降低,当WO_3负载量为24%时达到最优值,而HDS活性逐渐增强。

The γ-Al2O3 supported Ni-W catalysts with different metal contents for the hydroprocessing of low and middle-temperature coal tar were prepared and characterized by the X-ray diffractogram （ XRD ） , X-ray photoelectron spectroscopy （ XPS） , temperature programmed desorption of NH3（ NH3-TPD） , N2 adsorption and high resolution transmission electron microscopy （ HRTEM ） . The hydrodenitrogenation （ HDN ） and hydrodesulfurization （ HDS） performances of the catalysts were evaluated by using low and middle temperature coal tar. The results show that the sulfidation degree of the catalysts increases with increasing metal content within a certain range, while the amount of total acid that mainly consists of intermediate acid decreases. The HDN activity of the catalysts with Ni/W atomic ratio of 0 . 786 increases initially and reaches an optimum value at 24% WO3 , and then decreases, while the HDS activity increases gradually.