Two new four-connected zeolite-like magnesium aluminophosphates with intersecting 8-ring channels

Abstract

Two new Mg-containing aluminophosphates JU94 and JU95 (|C₄H₁₂N₂|[Mg₂Al₆(PO₄)₈(H₂O)₄]) have been hydrothermally synthesized in the same reaction system of MgO–Al₂O₃–P₂O₅–piperazine–H₂O. Both of their structures are constructed by the connection of AlO₄/MgO₄(H₂O)₂ polyhedra and PO₄ tetrahedra, forming two-dimensional intersecting 8-ring channels. Their frameworks exhibit distinct 4-connected zeolite-like topologies, as well as different dehydration behaviours during the calcinations. Their structure correlation has been discussed through the different linkage modes of Mg₂Al₃P₅O₃₀ building units. This work will provide insight into the synthesis and design of the novel MAPO (M = metal) molecular sieves.