Synthesis of regularly shaped AlPO4-11 molecular sieve through a solid transformation approach

Abstract

Abstract The development of efficient synthesis route is the main topic in practical applications and fundamental issues of molecular sieves. In this work, a new route for direct synthesis of regularly shaped aluminophosphate molecular sieve (AlPO4-11-S) is reported. The obtained molecular sieve is fully crystallized and show excellent physicochemical properties such as hierarchically porosity and high mechanical strength which meet the request for direct applications in industry. The key intermediates in the crystallization have been carefully investigated, from which the new insights into the molecular sieve formation mechanism are proposed. The water and n-DPA molecules well retained by ionic liquids in the initial dry extrudates play an important role in the formation of regularly shaped molecular sieve. This route shows great potentials in the industrial applications considering the features such as fewer synthesis steps, rapid crystallization, and obtaining materials with high content of molecular sieve, regularly shaped form, high mechanical strength and hierarchical pores.