Si含量对CO_2加氢制烃铁基催化剂的影响

以湿固相研磨法制备不同硅含量的铁基催化剂,采用X射线衍射、H2程序升温还原和傅里叶红外光谱对催化剂进行表征,在V(H_2)∶V(CO_2)∶V(N_2)=16∶8∶1、反应压力1.6 MPa、反应温度230℃、反应时间48 h和空速6 000 m L·(h·g-cat)-1条件下,在固定床反应器中考察催化剂的CO_2加氢制烃反应活性和烃类选择性。结果表明,随着Si O_2掺入量增加,催化剂的还原性能降低,结晶度呈下降趋势,CO_2转化率下降,但C5+烃类产物选择性在硅含量为10%时达到最大,为38.6%。

Effect of silica contents on iron-based catalysts for carbon dioxide hydrogenation to hydrocarbons

The iron based catalysts with different SiO₂ contents were prepared by wet-solid-phase grinding method.The catalysts were characterized by X-ray diffraction,H₂ temperature-programmed reduction and Fourier Transform Infrared Spectroscopy.Their catalytic properties for carbon dioxide hydrogenation were investigated in a fixed-bed reactor under the condition of V(H₂)∶V(CO₂)∶V(N₂)=16∶8∶1,reaction temperature 230 ℃,reaction pressure 1.6 MPa,space velocity 6 000 mL·（h·g-cat）^-1 and reaction time 48 h.The results indicated that with the content increase of SiO₂ mixed into iron oxide,the reduction performance of the catalysts became poor and the crystallinity degree was weaken.CO₂ conversion decreased,but the selectivity to C₅₊ hydrocarbons was up to 38.6% when SiO₂ content of the catalyst was 10%.