B. V. Suresh Kumar

Synthesis and characterisation of R3+ : AlPO4 (where R=Ce, Pr and Nd)

Abstract Aluminophosphate molecular sieve zeolites have been synthesised under hydrothermal conditions in the presence of structure directing agents such as organic amines. The addition of R3+ ions into the aluminophosphate framework not only enhances the stability of the framework but also enlarges the pore diameter, which helps in sieving larger molecules. Besides, it also enhances the catalytic efficiency in zeolites. The materials obtained have been subjected to a systematic characterisation such as powder X-ray diffraction (XRD), X-ray fluorescence (XRF) analysis, fourier transform infrared (FTIR), positron annihilation lifetime (PAL) measurements, Brunauer–Emmett–Teller (BET) surface area measurement and SEM.

Hydrothermal crystallization and characterization of R+3: AlPO4 zeolites, where R = Ce, Pr and Nd

Zeolites are the most important technological materials made up of framework of aluminosilicates, aluminophosphates, vanadophosphates, silicoaluminophosphates and so on. In the recent years the interest is being extended greatly from the molecular sieves to selective catalysis, gas adsorption, nanoparticle hosts, atmospheric ecosystems, etc. These aluminophosphate molecular sieve zeolites have uni-, two-, and three-dimensional channels which are obtained hydrothermally in the presence of organic amines as structure directing agents. VPI-5 is an important aluminophosphate molecular sieve with 18 tetrahedral rings and free diameter of 12.1 A. In this paper, the authors discuss the synthesis of R+3: aluminophosphate, where R=Ce, Pr and Nd.