摘要
以二氧化硫为还原剂,对铂钯置换后液中碲的还原反应进行研究。结果表明,往铂钯置换后液中添加盐酸使其Cl-浓度增加至1.0mol/L后,于75℃通入2h的二氧化硫,可将反应液中99%以上的碲还原沉淀,所得粗碲粉中碲含量在90%以上、杂质含量低。碲的还原沉淀效果随反应时间的延长、反应温度的升高、和反应液酸度的提高而增大,碲的还原反应是准一级反应,且反应属动力学控制。另外,提出了二氧化硫还原碲的反应机理模型,H+和Cl-都是二氧化硫还原碲的催化剂,都有利于将亚碲酸转变成氯化碲。
Reduction reaction of tellurium in Pt/Pd-replaced solution was investigated with sulfur dioxide as reductant. The results show that tellurium reduction rate is 99% above with Te content in raw-tellurium powder of 90% above under the conditions including Cl- concentration of 1.0 mol/L by adding hydrochloric acid, reaction temperature of 75℃, and aeration of SO2 gas of 2 h. Reduction of Te rises with increase of reaction duration, temperature, and acidity of solution. Reduction reaction of Te is in accordance with pseudo-first-order reaction controlled by kinetics. Mechanism model for reduction reaction between SO2 and Te is proposed, in which Cl- and H＋ are both regarded as catalytic species during transformation from tellurous acid to tellurium tetrachloride.
出处
《有色金属（冶炼部分）》
CAS
北大核心
2016年第9期35-38,共4页
Nonferrous Metals（Extractive Metallurgy)
关键词
铂钯置换后液
碲
二氧化硫
还原
催化
机理
Pt/Pd-replaced solution
tellurium
sulfur dioxide
reduction
catalysis
mechanism
