摘要
试验研究了杂质MgCl_2、NaCl和CaSO_4对氯化钾芒硝转化法制取硫酸钾过程的影响。试验指出,杂质MgCl_2对反应过程中K^2和(SO_4)^(2-)转化率及产品纯度的影响比较大。随着母液的循环,Mg^(2+)在溶液中积累至大约2.3％时,将以软钾镁砜(K_2SO_4MgSO_4·6H_2O)结晶析出。Na^+和Ca^(2+)对过程的影响较小。用化学纯和工业纯氯化钾与硫酸钠为原料制取硫酸钾的试验指出。由于工业纯原料含有Mg^(2+)、Na^+和Ca^(2+)等杂质,致使工业纯原料制得的硫酸钾产品纯度降低4～5％,K^+离子产率亦降低约4％。
The effects of impurities of MgCl_2, NaCl and CaSO_4 on production of K_2SO_4 from KCl and Na_2SO_4 have been studied under the conditions of labratorial experiments. The results show that MgCl_2 is the main impurity effeeting on quality of product and conversion of-K^+. When the concentration of Mg^(2+) in the solution accumulates up to 2.3％ during the mother solution cycle, the sehoenite (K_2SO_4·MgSO_4·6H_2O) will be deposited out in solid form. The effects of Na^+ and Ca^(2+) can be negligible. The comparison of the results between the test of using chemical and industrial-grade purity KCl and Na_2SO_4 as raw materials is made. It demonstrates that the purity of product and conversion of K^+ are lowered by 4-5％ and 4％ respectively using industrical-grade purity KCl and Na_2SO_4 as raw materials as eompared to using chemical-grade purity raw materials.
