用熔融结晶原理生产高纯碲的方法

Production Technology of High Purity Tellurium by Melt Crystallization Principle

高纯碲市场价格不断上涨,是因为适于高纯碲规模化生产的技术仍不成熟.真空蒸馏法、电解精炼法仅有少数企业在应用,化学方法则存在引进新的杂质或设备腐蚀等问题.因此,根据在二组分相图中,有纯组分与熔体共存区域的事实,发明了一种利用熔融结晶原理生产高纯碲的方法.将4N碲在470℃下熔融,再将熔体注入结晶器中,利用加热设备余热及熔体本身放热,使熔体缓慢冷却一定时间,再自然冷却至室温.对碲锭进行切割,先析出的<85%的结晶体为产品.该方法所用设备仅为一台密闭加热电炉和石英玻璃坩埚及石墨结晶器,操作很简单.适用于规模化生产,无需其他化学试剂,无设备腐蚀、无环境污染等其他问题.通过调节熔融结晶次数、结晶截取比例、缓慢冷却时间,企业可根据市场需求对碲的纯度、产量进行控制.经过一次结晶,碲的质量分数≥99.999.该方法有较高的工业应用价值.

Market prices of high purity tellurium continue to rise, because of high purity tellurium scale production technology is still not mature. Vacuum distillation, electrolysis refining method, only a few enterprises in the application, exist problems of chemical method such as introduce new impurities or equipment corrosion and so on. Therefore, according to the fact that in the two phase diagram, there is a pure component with melt coexistence region, invention a method of using melt crystallization principle for production of high purity tellurium. The 4N tellurium melt at 470℃ ,then melt into the mold ,utilization waste heat of equipment and heat of melt itself, to melt slowly cooling a certain time, then naturally cooling to room temperature. Cutting the tellurium ingot, it is the product that the 〈 85% of crystallization body of separation by crystallization at first. The equipment of the method used is only a closed heating furnace and the quartz glass crucible and the graphite crystallizer, the operation is very simple. It is suitable for large scale production, no other chemical reagents, no other problems such as equipment corrosion and environmental pollution etc. By adjusting the melt crystallization times, crystallization of interception ratio, slow cooling time, the enterprise can control the purity and yield of tellurium by the market demand. After the first crystallization, tellurium content ≥ 99. 999. This method has high value for industrial application.