Synthesis, characterization and investigation of catalysts containing Co-B

In this study cobalt borate synthesis was investigated using the reaction between cobalt chloride hexahdyrate, cobalt nitrate hexahydrate, cobalt sulphate heptahydrate and borax. The Co:B rates were chosen as 1:2, 1:3, 1:4, 1:5, 1:7, 1:10 and reaction temperatures 25, 35, 40, 45˚C. Suspension arised after reaction was filtered, washed and dried. The heat treatment carried out at 700, 850, 900 and 1000˚C during 1, 2, 3, 5, 7 hours. The samples were characterized by TG-DTA, XRD, FTIR, SEM, ICP-OES, BET and Rietveld analysis techniques. As reaction temperature and Co:B rates changed, two phases were obtained containing different amounts of cobalt tetraborate (CoB4O7) and cobalt pyroborate (Co2B2O5). It's seen that there are BO3 ve BO4 vibrations peaks. The samples which composed of one phase have small intensities of BO4 groups peaks. The presence of cobalt tetraborate phases was not found in XRD patterns of the samples that containing more than 90% cobalt pyroborate. There is no significant changes in microstructure among samples which were synthesized with different cobalt compounds. Mainly, microstructures of samples contains plates and rod-like forms together. The samples elemental analysis results were changed for Co amounts %23,08-34,84 and for B amounts %9,68-14,76. Keywords: Cobalt compounds, Reaction temperature, Co:B rates, Characterization