负载型磷化镍催化剂的空气表面改性法制备及其加氢脱氧性能

Preparation of supported nickel phosphide catalyst by surface modification method and its performance in hydrodeoxygenation

  • 摘要: 以MCM-41为载体,采用先前驱体氢气低温(673 K)还原、空气表面改性的方法制备了高活性的Ni2P/MCM-41催化剂,并采用XRD、BET、SEM、TEM、XPS和CO吸附等手段对催化剂进行了表征。以苯并呋喃(BF)加氢脱氧(HDO)为探针反应,考察了空气表面改性对Ni2P/MCM-41催化剂结构和HDO性能的影响。结果表明,空气表面改性得到的催化剂,活性相为单一的Ni2P;空气表面改性能够降低催化剂表面P物种的集聚,有助于小尺寸、高分散的Ni2P活性相的生成。在573 K、3.0 MPa、质量空速为4.0 h-1、H2/油体积比为500的条件下,Ni2P/MCM-41催化剂上BF转脱氧产物收率高达88%,较程序升温还原法制备的催化剂高50%。

     

    Abstract: With MCM-41 as support, the supported Ni2P/MCM-41 catalyst is prepared by first reducing the Ni2P precursors at low temperature (673 K) and then modifying the surface with air; the as-prepared Ni2P/MCM-41 catalyst was characterized by X-ray diffraction (XRD), N2-sorption, scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and CO uptake. The catalytic performance of Ni2P/MCM-41 in hydrodeoxygenation (HDO) of benzofuran (BF) was investigated to elucidate the effect of surface modification with air on the catalyst structure and HDO activity. The results show that pure Ni2P acts as the active phase on the surface of modified Ni2P/MCM-41 catalyst; the surface modification can decrease the aggregation of P species and promote the formation of small and highly dispersed Ni2P active phase. Under 573 K, 3.0 MPa, a weight hourly space velocity of 4.0 h-1 and a H2/oil volume ratio of 500, the yield of O-free products reaches 88% for HDO of BF over the modified Ni2P/MCM-41 catalyst, which is about 50% higher than that over the catalyst prepared by conventional temperature-programmed reduction method.

     

/

返回文章
返回