SEPARATION OF NITRIC ACID FROM AQUEOUS SOLUTIONS OF ALKALI METALS BY DIALYSIS.

Results of investigations into the diffusive dialysis of aqueous mixtures of nitric acid and an alkali metal salt are presented. The criterion of the separation characteristics of the system was determined from the ratio of the dialysis coefficients for the acid and the solutions. In considering the indices for the separation of nitric acid from alkali metal salts, it should be noted that the values for the dialytic ratios for nitric acid and alkali metal salts are rather high for all types of membranes, which allows one to include dialysis among potential methods for the separation of acid-alkali metal salt mixtures. Membranes based on grafted 2,5-methylvinylpyridine possess a high permeability which makes them preferable for use in dialysis apparatus. 5 refs.