发展中大孔型催化剂是催化裂化催化剂的主要发展方向之一, 催化裂化催化剂中引入中大孔的主要方法有高岭土酸碱改性法、引入大孔硅铝基材料法、引入介孔分子筛法、原位晶化法和模板法.酸碱改性高岭土的孔结构受原料影响较大, 孔径一般小于10 nm;制备大孔硅铝基材料替代拟薄水铝石可有效改善催化剂的孔结构, 但应关注对催化剂强度的影响;分子筛中引入介孔又包括水热处理法, 酸、碱处理法和引入不稳定位点法, 工业应用范围广, 但处理过程中易造成Y型分子筛结晶度下降, 并缺乏连续、贯通型孔道;原位晶化法是工业上较成功的中大孔催化剂制备方法, 但能耗相对高, 流程长;模板法可通过改变模板类型、含量对催化剂孔结构调变, 但应关注环保及催化剂强度问题.%Research of catalyst rich in meso-and macro-pores is the main development trend of FCC catalyst. At present main ways for preparing catalytic cracking catalysts with meso-and macropores are acid/alkali leaching of kaolin clay, adding macro-porous silica-alumina material, adding meso-porous zeolite, in-situ crystallization and template-preparing method. Macro-pores prepared by acid/alkali leaching of kaolin clay is always heavily impacted by the starting kaolin clay and pore diameter of as-prepared macro-pores are generally less than 10 nm. It is found that macro-porous silica-alumina material can substitute pseudo-boehmite to improve pore structures of FCC catalyst, but the attrition index should be noted. Ways to generate meso-pore in zeolite include hydrothermal treatment, acid/alkali treatment and implanting unstable sites, which apply widely in commercial application. But in these process, crystallinity of Y zeolite are seriously decreased and pore structure is lack of continuity and connectivity. In-situ crystallization is a commercial success for preparing FCC catalyst rich in meso-and macro-pores, but energy-consumption is high and production process is long. Template-preparing method can adjust pore structure by changing template type and content, but environment pollution and attrition index of the catalyst should be noted.
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