高稳定性介孔分子筛的粒径调变研究

发布时间：2018-03-05 21:05

  本文选题：介孔分子筛　切入点：前驱体组装　出处：《北京化工大学》2016年硕士论文　论文类型：学位论文

【摘要】：前驱体组装技术大幅提高了介孔分子筛的稳定性,为其在重油催化裂化中的应用奠定了基础。但是使用这种合成方法,介孔分子筛产物颗粒尺寸过大,给催化剂的制备带来了许多问题,所以在前驱体组装技术合成方法中,降低介孔分子筛产物的颗粒尺寸具有重大意义。在吐温20合成体系中,吐温20分解成聚氧乙烯山梨酸糖醇酐和酸钠皂,附着在Y型分子筛前驱体表面,降低其表面能从而减少产物的聚集,获得颗粒尺寸较小的产物。产物具有平均颗粒尺寸为8.500μm,其总比表面积875 m2.g-1,总孔容为0.97 cm3·g-1,平均孔径为3.42 nm；在经过水热处理10h后,总比表面积和总孔容的保留率分别为32%和32%,这说明产品具有良好的水热稳定性。在聚乙烯醇(PVA)合成体系中,PVA作为一种分散剂能够促进P123胶束在水溶液中的分散,为晶体形成更多的生长位点。另一方面,PVA分子通过氢键与产物结合,在其表面形成保护膜并呈现空间位阻效应,减少产物之间的聚集。表征结果显示产物的平均颗粒尺寸6.643μm,总比表面积850.7 m2g-1和孔容0.94 cm3 g-1,平均孔径为3.4 nm;在经过水热处理10 h后,其比表面积和孔容的保留率分别为32%和34%,说明产品具有’较好的水热稳定性。本论文在小试的基础上,实现了PVA体系10L放大合成。产物的平均颗粒尺寸8.6731μm,其总比表面积为856.1 m2.g小总孔容为0.67 cm3·g-11,平均孔径3.44 nm;在经过水热处理10h后,其比表面积和孔容的保留率分别为30%和34%,说明产物具有良好的水热稳定性。
[Abstract]:The precursor of assembly technology has greatly improved the stability of mesoporous molecular sieves, laid the foundation for its application in heavy oil FCC. But using this synthesis method of mesoporous molecular sieve product particle size is too large for the preparation of the catalyst has brought many problems, so in the precursor of assembling method, is of great significance to reduce the particle size of the mesoporous molecular sieve product. In 20 Twain Twain synthesis system, divided into 20 sugar alcohol polyoxyethylene sorbic acid anhydride and sodium soap, attached on the surface of the Y type sieve precursor molecules, thereby reducing the product can reduce the accumulation of its surface, obtain the product of smaller particle size products. With an average particle size of 8.500 m, the total surface area of 875 m2.g-1, general Kong Rong was 0.97 cm3 - g-1, the average pore size is 3.42 nm; after hydrothermal treatment of 10h, the total retention rate than the surface area and the total pore volume are 32% and 32%, this product has good thermal stability. In polyvinyl alcohol (PVA) synthesis system, PVA as a dispersant can promote the dispersion of P123 micelles in aqueous solution, for crystal formation growth of more sites. On the other hand, PVA molecules through hydrogen bonding and combination, form a protective film and a space the steric effect on the surface, reduce the aggregation between the product. The characterization results showed that average particle size of the product is 6.643 m, total 850.7 m2g-1 of surface area and pore volume of 0.94 cm3 g-1, the average pore size is 3.4 nm; after the hydrothermal treatment for 10 h, the ratio of retention rate of surface area and Kong Rong respectively. 32% and 34%, that "product has good hydrothermal stability. This paper on the basis of the experiment, the PVA system of 10L amplification product synthesis. The average particle size of 8.6731 m, the total surface area of 856.1 m2.g total pore volume was 0.67 cm3 - G-11, flat The average pore size is 3.44 nm, and the specific surface area and the retention rate of Kong Rong are 30% and 34% respectively after hydrothermal treatment of 10h, indicating that the product has good hydrothermal stability.

【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O643.36
，

本文编号：1571880