Highly efficient synthesis of LTA-type aluminophosphate molecular sieve by improved ionothermal method

Abstract

An LTA-type aluminophosphate molecular sieve has been successfully synthesized by an improved ionothermal method from a gel containing low-dosage ionic liquids. The optimum synthetic conditions of this material are refined. The resultant LTA molecular sieves were characterized by XRD, SEM, TG-DTA, CHN elemental analysis, solution ¹³C NMR, EDX, TEM and N₂ physisorption. The composition of the resulting LTA-type molecular sieves is determined to be (Al₁₂P₁₂O₄₈)(C₄H₉NO)₂(C₈H₁₅N₂⁺)₂(F⁻)₂, for which morpholine together with 1-butyl-3-methylimidazolium cations act as the structure-directing agent. The high zeolite yield, as well as the high specific surface area and micropore volume for the calcined LTA-type materials, imply that these zeolitic materials have a high potential in applications.