高纯三氯化锑的制备

Preparation of high purity antimony chloride

研究了SbCl3 HCl H2 O体系的相平衡 ,采用奥斯麦法 ,测定了含一定浓度三氯化锑的盐酸 (4 ,8,12mol/L)溶液的沸点以及液相和气相组成 ,绘制了该三元体系的温度 浓度和气相 液相组成图 ,研究了蒸馏体系中温度对砷蒸馏率和锑回收率的影响 .在此基础上 ,采用氯化 蒸馏 精馏的方法 ,从砷锑烟尘制备高纯三氯化锑 .首先将高砷锑烟尘在盐酸中浸出 ,并在大约 110℃蒸馏 ,部分三氯化砷 (质量分数为 87.6 7% )随盐酸和水被蒸馏出来 ,三氯化锑 (质量分数为 99.5 0 % )和某些金属氯化物溶解在浸出液中 ,某些不能被盐酸浸出的金属留在残渣中 ;然后从浸出液中用精馏法制备高纯三氯化锑 ,精馏柱保持温度范围为 12 0～ 2 2 0℃ ,获得的三氯化锑的纯度达到 99.999%以上 .这是一个变废为宝、减少污染。

Phase equilibrium of the SbCl 3 HCl H 2O system has been studied. By Othmer method, the compositions of gaseous and liquid phase and boiling points of HCl solution (4,8,12 mol/L) with certain concentrations of SbCl 3 were detemined. The phase diagrams of temperature concentration and composition of gaseous phase composition of liquid phase have been measured. And in distillation systems the temperature effects on distillation rate of As and recovery rate of Sb have been determined. Based on the phase equilibrium studying and concerned data, high purity SbCl 3 was prepared by chlorilation distillation rectification method. The flue dust containing As and Sb is first leached and distilled with HCl solution at about 110 ℃. A part of AsCl 3(87.67%) is distilled out with HCl and H 2O. SbCl 3(99.50%) and other metal chloridets are dissolved in the leaching solution. Some metals can not be leached by HCl solution and are left in the residue. Then from the leaching solution, high purity SbCl 3 can be prepared. The rectification column is maintained in the temperature range of 120～220 ℃. The purity of obtaining SbCl 3 is above 99.999%. This is a new process of changing waste to treasure, reducing environmental pollution and obtaining high quality product.