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The waste solution (CDWS) from HPF coke oven gas desulfurization process[1] is an extremely harmful pollutant.But the ammonium thiosulfate and ammonium thiocyanate contained in CDWS are of higher-value inorganic chemical products.The extraction of these salts will bring significant economic benefits to coking enterprises.Recovering method of ammonium thiosulfate and ammonium thiocyanate from the CDWS by fractional crystallization has been widely studied [2 3].But this method lacks of competitiveness in the market because of the imperfect process,the low purity and poor quality of the product[4].A new process of purify the ammonium thiocyanate by leaching-concentrated-crystallization (LCC) from mixed salt of CDWS has been developed by Taiyuan University of technology.The process appears simple,easy to control and high purity of ammonium thiocyanate can be obtained.In the paper,the relevant researches about leaching kinetics of ammonium thiocyanate by lea1 and lea2 were carried out,and the activation energy of ammonium thiocyanate leaching by lea1 and lea2 was compared.The results show that the ammonium thiocyanate extraction efficiency is increased as the extraction temperature increasing.Under the same conditions,the lea1 has higher extraction efficiency than lea2.The intermittent leaching process of ammonium thiocyanate is according to Spiro steady-state model[5].The activation energy of ammonium thiocyanate extraction with lea1 and lea2 is 6216.71J and 6845.16J respectively.