辉钼矿复合催化剂对哈密煤温和液化性能的影响及活性相变迁规律研究OA

Direct coal liquefaction under mild conditions,particularly at low reaction pressures,can effectively reduce both investment and operational costs.The availability of readily available catalysts with good hydrogenation performance is crucial for achieving the industrial application of direct coal liquefaction under mild conditions.Molybdenite was subjected to ultra-fine processing via mechanical activation to prepare MoS2 dispersions with varying particle sizes,which were then compounded with γ-FeOOH to fabricate a composite catalyst.The effects of mechanical activation time on the composition and dispersion of the catalyst were investigated using SEM,XRD and XPS characterization.The results indicate that extending the mechanical activation time facilitates the exposure of MoS2,the active component of molybdenite,on the mineral surface,while improving its dispersion within the catalyst.Utilizing a high-pressure autoclave test platform,direct liquefaction experiments were conducted on Hami coal under mild conditions with a reaction temperature of 450℃and a maximum pressure not exceeding 10 MPa.During the reaction process,the MoS2 in the composite catalyst remained stable,while γ-FeOOH transformed into Fe1-xS particles approximately 100 nm in size at 300℃.The XRD characteristic peaks of Fe1-xS shifted to lower angles during the heating process,accompanied by an increase in particle size,which stabilized after reaching 450℃.Compared with the iron-based catalyst,the composite catalyst demonstrated significant hydrogenation effects on asphaltenes during the 30 min‒60 min isothermal period at 450℃,achieving a maximum oil yield of 50.64%—an increase of 6.86%over that of the iron-based catalyst.