Studies On The Ionothermal Synthesis Of Aluminophosphate Molecular Sieve

Molecular sieve is a kind of material with rules of pore structure and ion exchange properties. It is widely used in petrochemical, coal chemical, fine chemical, biological separation, molecular devices, optical fields. In this work, aluminum phosphate molecular sieve are synthesized at 280℃ by ionothermal synthesis. The mechanism of ionothermal synthesis of aluminum phosphate molecular sieve is studied as well.1. The influence of different reaction conditions for synthesis of aluminum phosphate is studied. A appropriate reaction conditions is confirmed: using [BMIM]Br as solvent, n-DPA as template agent, P/Al=3 and the crystallization time is 8min.2. The study of the crystallization mechanism for AlPO4-5 and AlPO4-42 is done under the above reaction conditions. It is determined that the crystallization mechanism of AlPO4-5 and AlPO4-42 followed the solid phase transformation mechanism.3. The crystal transition process of AlPO4-5 aluminum phosphate molecular sieve is researched. A series of crystal transition process is found from AlPO4-5 to AlPO4-11 to cristobalite to MS. Through the results of SEM and UV Raman inferred that both solid phase transformation mechanism and liquid crystal transition mechanism are existed in the crystal transition process of AlPO4-5.