Abstract: Leaching process of sodium nitrate from nitratine using water was studied.In order to increase the mass fraction of sodium nitrate in leaching solution,different extracting times and liquid-solid mass ratios were selected to carry out the leaching experiments.Tests results indicated that leaching speed of nitratine was rather fast,balances were all achieved within 10 min under the different liquid-solid mass ratios;under the same time condition,liquid-solid mass ratio of 1.0 would be appropriate.Leaching rate of sodium nitrate could reach 90%.Under the conditons of 25 ℃,liquid-solid mass ratio of 1.0 and leaching time of 10 min,extractable liquid was repeated 6 times to do the leaching,the mass fraction of sodium nitrate in leaching sloution increased from 5.54% to 29.58%,while the mass fraction of sodium chloride reduced from 12.03% to 11.89% and the mass fraction sodium sulfate reduced from 3.22% to 1.87% comparing with those in the initial leaching solution.With the aid of phase diagram,a method of grading spray was proposed for leaching sodium nitrate in real production.

Key words: nitratine；sodium nitrate, leaching