THE SYNTHESIS OF HIGH COBALT-CONTAINING COAPO-34

High cobalt-containing CoAPO-34 has been synthesized using tetraethyla mmonium hydroxide (TEAOH) and [(CH3CH2)(4)N]2CoCl4 as a cobalt source and additional templating agent. Pure CoAPO-34 was obtained by replaci ng up to 0.4 mol fraction of the aluminum by cobalt in the reaction ge l at varying template concentrations. The crystallization of CoAPO-34 with impurities occurs at 0.5 mol fraction substitution and above. Ana lysis and characterization of the products by X-ray diffraction (XRD), X-ray fluorescence (XFR), infrared (i.r.) spectroscopy, thermogravime tric analysis (t.g.a.), and Scanning Electron Microscopy (SEM) is desc ribed. X-ray diffraction has shown an increase in d-spacings relative to AIPO(4)-34, and chemical analysis has shown samples containing arou nd 30% framework cobalt. The unit cell, found to be hexagonal in symme try, increases in volume between the 0.2 and 0.4 mot fraction substitu tion levels, but little change is observed in unit cell size between t he 0.4 and 0.5 mol fraction substitution level. This has been explaine d in terms of changing bond lengths and angles with increasing framewo rk substitution of cobalt. Infrared spectroscopy has shown a decrease in the frequencies of the asymmetric and symmetric stretching regions and in the T-O bending region with increasing cobalt content.