重质油分子结构复杂、尺寸较大且容易聚集形成缔合体,致使在加氢及催化裂化催化剂孔道内存在明显的扩散阻力,显著阻碍了反应物分子与催化剂孔道内部活性位的接触,导致反应速率与转化率明显低于轻质原料.因此,研究重油分子在催化剂孔道内扩散受阻情况可以为催化剂的设计优化提供信息与指导.尽管借助仪器或膜材料能获得溶质分子的扩散性能,但与反应条件下扩散规律差别较大,因此在实际反应体系下获得重油分子在催化剂孔道中的扩散传质具有重要的现实意义.综述采用反应动力学手段获得扩散传质数据并建立受限因子关联模型及其影响因素的研究进展,从反应物选择、反应条件及催化剂等因素的优化角度对重油分子受阻扩散研究进行展望.%Due to the structural complexity,large size and aggregation property of heavy oil,significant dif-fusion resistance apparently exists in the pore channels of hydrotreating and catalytic cracking catalysts. Therefore,the interactions between the heavy oil molecules and the catalyst active sites are significantly hindered,which results in the relatively lower reaction rate and conversion than those of the light feed-stocks. Thus,further study on the diffusion of heavy oil molecules through catalyst pores can provide infor-mation and guidance for the design of catalyst. Although some diffusion properties of solute molecules have been obtained by instruments and film material,there exists great difference between them and that acquired under the reaction conditions. Therefore,gaining the diffusion properties of heavy oil molecules under conditions of realistic reaction possesses vital important practical meanings. Based on the reaction kinetic method,the research progress in the empirical correlation for the restrictive factor of model com-pounds,narrow fractions and heavy oil were summarized. Moreover,the key parameters of restrictive factor were also discussed. Finally,the future development in restrictive diffusion of heavy oil was proposed from the perspective of reaction conditions,reactant property and catalysts selection.
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