[en] The paper describes the studies carried out for the separation of nitrate from hexamethylenetetramine (HMTA) and urea which are present in the alkaline waste generated during preparation of UO₃ microspheres by sol-gel process. For separation, Dowex 1 X 4 was used as ion exchanger and 0.5 M NaOH was used as eluent. Experiments were conducted both under batch equilibration conditions as well as through column. The distribution ratio data for nitrate at different equilibrium concentration in solution phase were used to determine the capacity of the resin. The batch equilibration as well as column experiments showed that nitrate can be separated. The studies quantified the extent of nitrate removal from the waste and the amount of additional waste generated. (author)