【作者】 刘宏海；

【导师】 马建泰； 高雄厚；

【作者基本信息】 兰州大学 ， 物理化学， 2006， 博士

【摘要】 流化催化剂裂化(FCC)一直是现代炼油工业的核心技术。FCC装置的目的就是使重油和渣油转化为轻质产品。随着炼油成本的提高和原油重质化，掺炼渣油已经成为一种趋势。因此，较高的活性、良好的选择性及优异的重油转化能力是对渣油FCC催化剂的基本要求，直接影响着炼厂效益。为此，催化剂的设计理念已发生了很大变化，主要包括两个方面：一是催化剂中的分子筛含量逐渐提高，一是更加注重基质与活性组分的协同作用，以不断满足原料劣质化和效益最大化的要求。 一般地，提高FCC催化剂中的Y分子筛含量将改善催化剂的活性和选择性。但是，随着分子筛含量的提高，往往需要更多量的粘结剂以保证催化剂的强度，可是粘结剂用量的加大，将对催化剂的孔结构产生不利影响，为避免上述不利影响，一个有效的解决途径是采用原位晶化。其产品的主要特点是活性高、重油转化能力增强、催化剂寿命延长。因此，利用原位晶化工艺的优点，合成出分子筛含量大于40％的高分子筛含量的晶化产物，将进一步提升催化裂化催化剂的反应性能。本研究的主要内容之一就是充分利用原位晶化的反应特点，通过对晶化反应过程的深入研究，大幅度提高原位晶化合成分子筛的含量，开发出性能优良的FCC催化剂。 研究过程中，将喷雾干燥成型的高岭土分为两部分，在不同焙烧温度下分别制备成偏高岭土微球(偏土)和充分焙烧高岭土(高土)，将高土和偏土按照一定比例混合，在优化的水热晶化条件下合成出了NaY分子筛含量大于40％的晶化产物，晶化产物经离子改性和超稳化处理后，制备出新型原位晶化FCC催化剂。与对比剂相比，该催化剂具有活性高、比表面高、孔分布理想的特点。 将催化剂人工污染5000ppm的钒和3000ppm的镍后，在中型提升管对催化剂的反应性能进行了评价。新开发的原位晶化催化剂表现出良好的催化反应性能和优异的抗重金属污染能力。与对比剂相比，在相当的焦炭选择性下，原更多还原

【Abstract】 It is known that the activity and selectivity of the FCC catalyst tend to beimproved greatly with the increase of the Y-faujasite content. However, the increasedzeolite contents usually require sufficient binder to achieve good attrition resistance.The high content of binder usually leads to coating of the zeolite crystal surfaces andocclusion of potentially beneficial external acvtive sites. To avoid this disadvantage,in this paper, we used the in-situ synthesis method by pre-prepared kaolinmicrospheres and succeesfully prepared a Y/Kaolin microsphere composite with Y’srelative crystallinty above 40% and SiO₂/Al₂O₃ ratio of 4.83. XRD, N₂adsorption-desorption, SEM, FT-IR were employed to chacterize this composite.Physicochemical data indicated, compared to the nomal NaY, this microspherecomposite has more hydrothermal stable macro-pore structures, and the externalsurfaces of these Y zeolite crystallites are exposed and accessible to the feedmolecules. After modification and steaming treatment, a novel FCC catalyst wasprepared. The reaction data indicated that, compared to a commercial catalyst atsame operation conditions and similar coke selectivity, the.high zeolite Y contentin-situ catalyst have evident advantages on slurry yield （8.68% lower）, conversionrate （10.33% higher） and liquid yield （7.6% higher）. From PONA analyses, we canalso clearly see that the olefins content reduced greatly and RON improved markedlywith in-situ catalyst because of its higher zeolite content. Therefore, this novelin-situ catalyst with higher zoelite content has more adaptability for resid cracking.Then a novel FCC catalysts mixture was prepared by adding a semi-syntheticadditive catalyst with 35wt% of HZSM-5 to the above catalysts prepared by in-situ synthesis method. It was evaluated on Advanced Catalyst Evaluation （ACE） reactor. Catalytic cracking test showed, compared with a commercial propylene-improved FCC catalyst, the propylene yield ot our novel FCC catalyst is increased by 1.265% and propylene selectivity by 2.93%. At the same time, coke yield is decreased by 1.994% and total liquid yield is increased by 0.965%.更多还原