本文综述了甲烷转化制合成气镍催化剂积炭的研究进展,论述了积炭热力学和动力学、积炭类型、积炭机理和影响积炭的因素,详细分析了催化剂的镍粒子尺寸、镍-载体相互作用、载体碱性强度、载体氧化-还原性质和添加助剂对镍催化剂的积炭速率和积炭量的影响,并总结了重整反应工艺参数和反应器形式对镍催化剂积炭的影响。最后指出,采用现代表征手段阐明镍催化剂的积炭机理、种类和数量,明确积炭的规律,可为设计开发抗积炭性能强的镍催化剂提供理论依据;可通过增强金属与载体的相互作用、减小镍粒子的尺寸(镍粒子尺寸小于20 nm)和选择适宜的载体来制备抗积炭性能强的催化剂;可通过采用流化床反应器且优化工艺参数来减少重整过程积炭量;可通过寻求行之有效的积炭催化剂再生方法来解决镍催化剂积炭问题。
In this paper, the recent research progresses in carbon deposition on the Ni catalysts for conversion of CH4 to synthesis gas has been summarized. The thermodynamics, kinetics and type of coke, the mechanism of carbon deposition, and the impact factors of coke formation are discussed. The effects of nickel particles size, the alkali strength degree and redox properties of supports, the interaction between nickel and supports to the amount and the type of coke deposition have been substantially analyzed. By using modern characterization measures, the mechanism, type, and amount of carbon deposition in this methane reforming reaction and elements which influence the carbon deposition are reviewed in detail, which can provide a theoretical basis for the design and development of resistance to coke properties of nickel catalyst. The well anti-coke performance catalyst can be prepared by enhancing the interaction between Ni and supports, improving the degree of dispersion of Ni on the carrier, reducing the size of Ni particles (less than 20 nm). Less amount of coke formation can be achieved by using fluidized bed reactor than fixed bed, optimizing the process parameters, and seeking for the effective regeneration method of used carbon deposition catalyst.