关键词: 煤直接液化, FeOOH催化剂, 改性, 助剂, 共沉淀, 油收率

Abstract:

Modified FeOOH catalysts were prepared by a co-precipitation method using Si, Al, La, Ca, Mg, Zr, Cu, Ni and Co as promoters, respectively. The effects on microstructures, crystalline phase and morphology of the catalysts were characterized by BET, XRD and SEM. Their catalytic performances for the direct liquefaction of Shendong coal were evaluated in a 0.5 L stirring autoclave. The results showed that these promoters (Si, Al, Ca, Zr, Ni and Co) could improve the dispersion of the catalysts and surface area, and then improve the catalytic performances for direct coal liquefaction. Increasing by 0.7%—2.7% oil yield over the unmodified the catalyst could be obtained. However, Mg showed no effect on catalytic ability, while Cu and La reduced the Oil yield. The result indicated that Si, Al, Ca and Zr as the structure promoters could significantly improve the texture properties of catalysts, resulting in an increase of γ-FeOOH crystalline phase with small size which was beneficial to form active phase (Fe_1-xS). Co and Ni as the electronic promoters could activate H₂ preferentially to promote liquefaction, leading to the rising in oil yield.

Key words: direct coal liquefaction, FeOOH catalyst, modify, promoter, co-precipitation, oil yield