Hydrothermal Synthesis of New Pure Beryllophosphate Molecular Sieve Phases from Concentrated Amines

Citations Over TimeTop 10% of 2001 papers

Abstract

A few new pure beryllophosphate molecular sieves have been hydrothermally synthesized by using concentrated amines such as triethylene tetramine, polyethylene polyamine, piperazine, and pyridine as structure-directing agents. The structures of these compounds were characterized by single-crystal X-ray diffraction. Their structures are similar to the zeolite gmelinite, gismondine, and ABW frameworks, named BePO4−GME, BePO4−GIS, and BePO4−ABW, respectively. BePO4−GME is the first instance of phosphate with GME topology. The organic template was found in the 12-membered ring channels running along [001]; the thermal analysis indicates that the inorganic framework collapses above 400 °C after the removal of the template. BePO4−GIS is a new beryllophosphate, which has three-dimensional, intersecting 8-membered ring channels along the crystallographic [001], [010], and [111] directions. In the concentrated amines system these resulting compounds have similar structural characterizations: Their frameworks that are built up from the connection of BeO4 and PO4 tetrahedra all have a 4.8.8 network and can be viewed as built from a different number of cross-linked chains (threes for BePO4−GME and fours for BePO4−GIS and BePO4−ABW). Crystal data for BePO4−GME1: trigonal, space group P1c, a = 13.056(8), b = 13.056(8), c = 9.485(6) Å, V = 1400(2) Å3, Z = 12, R1 = 0.0513, Rw = 0.1519. Crystal data for BePO4−GIS: monoclinic, space group C2/c, a = 13.514(2), b = 9.0119(10), c = 9.6357(11) Å, β = 134.507(2)°, V = 836.9(2) Å3, Z = 4, R1 = 0.0460, Rw = 0.1455. Crystal data for BePO4−ABW: orthorhombic, space group Pna21, a = 8.7173(8), b = 8.5889(8), c = 4.9673(5) Å, V = 371.91(6) Å3, Z = 4, R1 = 0.0304, Rw = 0.0805.

Related Papers

• → Controlled Structural Variations in Templated Uranium Sulfates(2003)68 cited
• → Krypton adsorption on microporous carbons and 5A zeolite(1969)18 cited
• Research Progress in Synthesis of Meso/microporous Composite Molecular Sieves by Using Alkali-treated Microporous Molecular Sieve(2013)
• Synthesis and characterization of a novel microporous SAPO material with RHO topology(2010)
• → Templating agent-free process for the manufacture of microporous, crystalline aluminophosphate molecular sieves(1993)