The production of well-shaped, spherical, and hydrothermally stable catalyst additives is a complex task in catalytic cracking. Industrial solutions often involve the use of phosphate materials. In this work, we prepared a spherical catalyst grain by spray-drying zeolite (ZSM-5) and kaolin filler with three different aluminum phosphate binders. The phosphate binders were used as pure binders and in combination with colloidal silica. We prepared the aluminum phosphate binders from boehmite and phosphoric acid with three different P/Al ratios. All of these can effectively bind the catalyst components to spherical particles. We demonstrated that various combinations of aluminum phosphate binders with colloidal silica can modify the catalyst’s porosity, acidity, stability, and hydrocarbon cracking properties. Finally, we found that the use of a silica-containing aluminum phosphate binder and a total P/Al ratio below 1 is necessary to avoid pore blockage by phosphates and to reduce the acidity of the catalyst. As a result, the aluminum phosphate binder can improve both the hydrothermal stability of the zeolite and the catalyst grains as well as the yield of light olefins in hexane cracking test reactions.

中文翻译：

---

磷酸铝增强 ZSM-5 裂化添加剂的水热稳定性


生产形状良好、球形且水热稳定的催化剂添加剂是催化裂化中的一项复杂任务。工业解决方案通常涉及使用磷酸盐材料。在这项工作中，我们通过喷雾干燥沸石（ZSM-5）和高岭土填料与三种不同的磷酸铝粘合剂制备了球形催化剂颗粒。磷酸盐粘合剂用作纯粘合剂并与胶体二氧化硅结合使用。我们用勃姆石和磷酸制备了三种不同 P/Al 比的磷酸铝粘合剂。所有这些都可以有效地将催化剂组分结合到球形颗粒上。我们证明了磷酸铝粘合剂与胶体二氧化硅的各种组合可以改变催化剂的孔隙率、酸度、稳定性和烃裂化性能。最后，我们发现使用含二氧化硅的磷酸铝粘合剂和低于1的总P/Al比对于避免磷酸盐堵塞孔并降低催化剂的酸性是必要的。因此，磷酸铝粘合剂可以提高沸石和催化剂颗粒的水热稳定性以及己烷裂解测试反应中轻质烯烃的产率。