Abstract
The conditions for forming KA1CO3 (OH), from potassium aluminate solution by method of blowing CO, were examined and its physicochemical properties were investigated by X-ray diffraction analysis, thermal analysis, infrared spectrometry and electron microscopic observation etc.
KA1CO3 (OH), was formed in almost 100% when there was a large amount of HCO3- in potassium aluminate solution where alkali was neutralized and aluminate ion was present in a supersaturated state. Those conditions were satisfied when the molar ratio of 120/A1, O2- of the potassium aluminate solution was 8-10, the reaction temperature 80-90° C, and CO, was blown into the solution sufficiently.
From the results of formation conditions and infrared absorption spectroscopic analysis etc, its rational formula was appropriate to represent KA10 (OH)HCO, . Carbon dioxde in synthetic KA10 (OH)HCO, was evolved by heating 320-400° C and lattice OH was dehydrated by heating 690-740° C to be KA1O2- which was very hygroscopic crystal.
The activated energy of decarbonation was 64.1 kcal/mol. KA10 (OH) HCO, had a true specific gravity of 2.40 and was in a needleshaped crystal by electron microscopic observation.
