(1. 廣西堂漢鋅銦股份有限公司 博士后科研工作站, 南丹 547200;
2. 中南大學(xué) 冶金科學(xué)與工程學(xué)院，長(zhǎng)沙 410083)
摘 要: 對(duì)Bi2S3-ZnO-Na2CO3低溫熔鹽體系進(jìn)行熱力學(xué)分析，計(jì)算了在700～1 500 K溫度下體系中各反應(yīng)的標(biāo)準(zhǔn)吉布斯自由能變化值( )，并繪制了相應(yīng)的 —T圖。熱力學(xué)分析結(jié)果表明，在700～1 100 K溫度范圍內(nèi)，Bi2S3中的Bi會(huì)被C還原成金屬Bi進(jìn)入金屬相中，S將以ZnS形式進(jìn)入固體物渣中。根據(jù)分析結(jié)果，在700～ 1 100 K溫度下，以Na2CO3等鈉鹽為熔劑、ZnO為固硫劑、粉煤為還原劑，開展了驗(yàn)證試驗(yàn)。試驗(yàn)得到了直收率達(dá)98%的粗鉍，S幾乎100%以ZnS的形式固定在渣中，與熱力學(xué)分析結(jié)果一致。
關(guān)鍵字: 低溫熔鹽；熱力學(xué)分析；清潔冶金
（1. Post-doctoral Scientific Research Center, Guanxi Tanghan Zinc & Indium Co., Ltd., Nandan 547200, China;
2. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The thermodynamic analysis of Bi2S3-ZnO-Na2CO3 low temperature molten salt system was carried out. Based on calculating reactions entropy ( ) of this low temperature molten salt system at 700−1 500 K, the relationship between and reaction temperature (T) within this temperature range was obtained. The results of thermodynamic analysis show that bismuth in Bi2S3 can be reduced by carbon to metal Bi and then get into the metal phase, and sulfur can be fixed in ZnS and get in solid slag. By using soda and other sodium salt as flux, zinc oxide as sulfur additives, coal or coke powder as reducing agent, two verification experiments were carried out at 700−1 100 K. The verification test results show that crude bismuth can be obtained at this low temperature. Bismuth direct yield is greater than 98%, and all sulfur embraced in raw materials can be fixed as zinc sulfide. The verification test results are in accordance with the thermodynamic analysis results.
Key words: low temperature molten salt; thermodynamic analysis; clean metallurgy
