ETHYLENEDIAMINE EFFECT ON CO2+ UPTAKE BY ZEOLITE-Y

Co2+ ion exchange, at room temperature, from aqueous cobalt - sodium chloride solutions with NaY zeolite has been studied. The effect of contact time on the shape of the sorption curves of Co2+ using zeolite Y dehydrated at 600 degrees C is similar to the one found in our previous work with a zeolite dehydrated at 150 degrees C. A fast sorption uptake is observed in which 1.8 meq of Na+ ions/g of zeolite are replaced by cobalt ions followed by a desorption process where the uptake decreases to 1.2 meq/g zeolite. The Co2+ sorption using zeolite Y dehydrated at 600 degrees C is increased when ethylenediamine solution is passed through the zeolite. The Co2+ sorption uptake, initially 2.0 meq/g, increases to 2.8 meq/g of zeolite. This behavior is explained by the location and coordination of cobalt in zeolite Y sites. It is suggested that the highest uptake process is due to the blocking of zeolite sites by a Co complex compound.