本文選題：碲鋅鎘 + 水熱氧化��； 參考：《浙江理工大學(xué)》2015年碩士論文

【摘要】：從碲鋅鎘中提取金屬碲不僅具有非常高的經(jīng)濟效益,而且是一項變廢為寶的資源綜合利用工程。本研究根據(jù)碲鋅鎘原料的成分和原料中碲存在的形態(tài),提出先將碲鋅鎘水熱氧化,接著酸浸,最后還原提取碲。碲鋅鎘氧化的探索實驗表明：采用NaClO3和HNO3氧化,實驗過程中會產(chǎn)生有害氣體；采用H2O2和熱處理氧化,碲的提取率不是很高；采用KMnO4氧化,提取出碲的純度不是很高；采用水熱氧化時,碲的提取率為58.80%,純度為99.21%,且不會產(chǎn)生有害氣體。因此,本實驗碲鋅鎘采用水熱氧化。本論文首先對碲鋅鎘水熱氧化進行了研究,考察了H2O2加入量、水熱溫度、水熱時間和溶劑濃度這四個因素對碲的提取率的影響,確定碲鋅鎘水熱氧化的最佳條件為：H2O2加入量10.0 mL,水熱溫度180℃,水熱時間6 h,溶劑稀硫酸的濃度2 m0l/L.碲鋅鎘水熱氧化后酸浸還原提取碲,對第一種方案：H2SO4浸出--Na2SO3還原進行了研究,考察了：酸浸時硫酸濃度、液固比、酸浸溫度、酸浸時間、碲鋅鎘粒徑、氯化鈉加入量、亞硫酸鈉加入量、還原溫度和還原時間這九個因素對碲的提取率的影響,確定最佳條件為：酸浸硫酸濃度8 mol/L,液固比12：1,酸浸溫度85℃,酸浸時間4 h,碲鋅鎘的粒徑120～300目,還原時NaCl/Te=6,Na2SO3/Te=10,還原溫度80℃,還原時間80 min。在最佳條件下,碲的提取率為81.27%。在第一種方案的基礎(chǔ)上,對第二種方案：H2SO4+NaCl浸出--Na2SO3還原進行了研究,主要考察了酸浸硫酸濃度、液固比、氯化鈉加入量、亞硫酸鈉加入量等因素對碲的提取率的影響,確定最佳條件為：酸浸時加入8.00 g氯化鈉,硫酸濃度4mol/L,酸浸時間15 min,液固比10：1,還原NaCl/Te=6,Na2SO3/Te=10,其他條件與第一方案的相同。在最佳條件下,碲的提取率為91.39%。第二種浸出還原方式相對于第一種方案,減少了酸浸的時間和降低了酸浸硫酸的濃度,同時提高了碲的提取率。綜上所述,本論文碲鋅鎘中提取碲的工藝為：先將碲鋅鎘水熱氧化,接著H2SO4+NaCl浸出,最后用Na2SO3還原溶液中的碲。
[Abstract]:The extraction of metal tellurium from cadmium zinc tellurium not only has high economic benefit, but also is a comprehensive utilization project of transforming waste into treasure.According to the composition of zinc cadmium tellurium and the form of tellurium in the raw material, the hydrothermal oxidation of cadmium zinc tellurium was put forward, then the acid leaching was carried out, and finally the tellurium was extracted by reduction.The experimental results of cadmium cadmium tellurium oxidation show that harmful gases will be produced in the process of oxidation by NaClO3 and HNO3, the extraction rate of tellurium by H2O2 and heat treatment is not very high, the purity of tellurium extracted by KMnO4 oxidation is not very high.By hydrothermal oxidation, the extraction rate of tellurium is 58.80, the purity is 99.21, and the harmful gas will not be produced.Therefore, zinc cadmium tellurium was hydrothermal oxidized in this experiment.In this paper, the hydrothermal oxidation of zinc cadmium tellurium was studied. The effects of H2O2 addition, hydrothermal temperature, hydrothermal time and solvent concentration on the extraction rate of tellurium were investigated.The optimum conditions for hydrothermal oxidation of cadmium zinc tellurium were determined as follows: the amount of H _ 2O _ 2 was 10.0 mL / L, the hydrothermal temperature was 180 鈩，

本文編號：1746649