(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 采用硫酸浸出−二氧化硫還原方法從中和渣中制取單質(zhì)碲。研究表明：采用硫酸浸出中和渣，當(dāng)反應(yīng)溫度為30 ℃、反應(yīng)時(shí)間為0.5 h、硫酸濃度為53.9 g/L、硫酸用量為理論用量的1.5倍時(shí)，碲浸出率為99.99%；采用亞硫酸鈉還原酸浸液中碲時(shí)，碲(Ⅳ)發(fā)生水解生成二氧化碲；采用二氧化硫還原酸浸液中碲時(shí)，當(dāng)反應(yīng)溫度為75 ℃、反應(yīng)時(shí)間為2 h、鹽酸濃度為3.2 mol/L、二氧化硫流量為0.4 L/min時(shí)，碲回收率達(dá)到99.84%。X射線衍射(XRD)分析表明二氧化硫還原得到的產(chǎn)物為單質(zhì)碲，電感耦合等離子體發(fā)射光譜(ICP)分析表明，碲粉中碲含量為98.27%。掃描電子顯微系統(tǒng)(SEM)分析表明，碲粉的形態(tài)為針形。
關(guān)鍵字: 碲渣；硫酸浸出；SO2；碲
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The elemental tellurium was prepared from neutralization sludge by the method of sulfuric acid leaching and sulfur dioxide reduction. The results shows that, in the process of sulfuric acid leaching of neutralization sludge, the leaching rate of tellurium is 100% when the reaction temperature is 30 ℃, reaction time is 0.5 h, sulfuric acid concentration is 53.9 g/L, the dosage of sulfuric acid is 1.5 times of the theoretic addition. Te(Ⅳ) turns to tellurium dioxide when the acid leaching solution is reduced by sodium sulfite. The recovery ratio of tellurium is 99.84% by sulfur dioxide reduction when the reaction temperature is 75 ℃, reaction time is 2 h, hydrochloric acid concentration is 3.2 mol/L, sulfur dioxide flow rate is 0.4 L/min. X-ray diffractometry (XRD) analysis shows that the reduction product is in the forms of elemental tellurium. Inductively coupled plasma-atomic emission spectrometry (ICP) analysis shows that the content of tellurium in the product is 98.27%. Scanning electron microscopy (SEM) analysis shows that the form of powdered-tellurium is needle.
Key words: tellurium sludge; sulfuric acid leaching; SO2; tellurium
