Sb_(2)S_(3)-HgS-O体系热力学分析及锑汞分离工艺研究

Thermodynamic analysis and separation on antimony and mercury from Sb_(2)S_(3)-HgS-O system

锑汞共生矿所含锑汞矿物无法用选矿方式获得独立汞精矿或锑精矿等单一精矿,但在混合浮选情况下,锑和汞的硫化矿物能以高回收率进入含锑汞物料中。本文对挥发焙烧法处理含锑汞物料分离锑汞的热力学和选择性氧化挥发焙烧工艺条件进行了研究,结果表明:升温有利于反应进行,主要产物为Sb_(2)O_(3)和Hg0,焙烧温度要小于1323 K;含锑汞物料中各种物质的饱和蒸汽压存在差异,挥发先后顺序为Hg→HgS→Sb_(2)O_(3)→Sb_(2)S_(3)→Sb;Sb_(2)S_(3)氧化先后顺序为Sb_(2)S_(3)→Sb→Sb_(2)O_(3)→Sb_(2)O_(4)→Sb_(2)O_(5),高温、高氧势、低硫势有利于锑的氧化;选择性氧化挥发焙烧最佳工艺条件为:焙烧温度1273 K,焙烧时间30 min,料层厚度9 cm,鼓风量15 L·min^(-1)。在此工艺条件下,锑挥发率大于96.87%,锑氧粉回收率达到96%以上;汞挥发率大于99.99%,汞回收率可达98%以上。该研究为锑汞分离工业化生产提供初步可行的试验条件。

The antimony and mercury minerals contained in the antimony mercury coexisting ore cannot be obtained through mineral processing to obtain independent mercury concentrate or single antimony concentrate.However,in the case of mixed flotation,the sulfide minerals of antimony and mercury can enter the antimony⁃mercury composite concentrate with high recovery rate.The thermodynamics of separating antimony and mercury from antimony⁃mercury composite concentrate by volatilization roasting and the process conditions of selective oxidation volatilization roasting were studied.The results show that the heating⁃up is beneficial to the reaction,the main products are Sb2O3 and Hg0,and the roasting temperature should be less than 1323 K;the saturated vapor pressure of various substances in antimony⁃mercury composite concentrate is different,and the volatilization order is Hg→HgS→Sb_(2)O_(3)→Sb_(2)S_(3)→Sb;the oxidation order of Sb_(2)S_(3)is Sb_(2)S_(3)→Sb→Sb_(2)O_(3)→Sb_(2)O_(4)→Sb_(2)O_(5);high temperature,high oxygen potential and low sulfur potential are beneficial to the oxidation of antimony,the optimal process conditions for selective oxidation volatilization roasting are as follows:the roasting temperature is 1273 K,roasting time is 30mins,material layer thickness is 9 cm,blast volume is 15 L·min^(-1),under these conditions,the volatilization rate of antimony is more than 96.87%,and the recovery rate of antimony oxide powder is more than 96%,volatilizaion rate of mercury is greater than 99.99%,and recovery rate of mercury is more than 98%.The study provides preliminary feasible experimental conditions for industrial production of antimony mercury separation.