(1. 中南大學(xué) 化學(xué)化工學(xué)院，有色金屬資源化學(xué)教育部重點(diǎn)實(shí)驗(yàn)室，長(zhǎng)沙 410083；
2. 株洲冶煉集團(tuán)股份有限公司，株洲 412000)
摘 要: 利用化學(xué)反應(yīng)的標(biāo)準(zhǔn)平衡常數(shù)求得冶煉廢渣熔池熔煉過程中5種金屬硫酸鹽(FeSO4, In2(SO4)3, Fe2(SO4)3, ZnSO4, PbSO4)的分解壓，確定硫酸鹽在高溫下發(fā)生分解反應(yīng)的溫度；采用熱重(TG)及差示掃描量熱(DSC)分析各金屬硫酸鹽的分解過程，驗(yàn)證熱力學(xué)計(jì)算結(jié)果。結(jié)果表明，5種硫酸鹽發(fā)生分解反應(yīng)由易到難的順序?yàn)镕eSO4、In2(SO4)3、Fe2(SO4)3、ZnSO4、PbSO4；熱力學(xué)計(jì)算得到的相變溫度、分解溫度與DSC曲線吸熱峰位置、TG曲線質(zhì)量損失階段相吻合，且理論計(jì)算溫度比TG-DSC測(cè)定溫度低7.5~283.1 K；熔煉爐溫度達(dá)到1316.1 K以上可使浸鋅渣、沉鐵渣中的硫酸鹽分解脫硫較徹底。
關(guān)鍵字: 冶煉廢渣；金屬硫酸鹽；熔池熔煉；熱力學(xué)計(jì)算
（1. Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education,
School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. Zhuzhou Smelter Group Co., Ltd., Zhuzhou 412000, China）
Abstract:The decomposition pressures of five metal sulfates (FeSO4, In2(SO4)3, Fe2(SO4)3, ZnSO4, PbSO4) in smelting slag were calculated with the standard equilibrium constants of related chemical reactions and the sulfate decomposition temperatures were obtained by the pressures. The metal sulfates decomposition was investigated through thermogravimetric (TG) and differential scanning calorimetry (DSC), and the TG-DSC analysis confirmed the results of thermodynamic calculation. The results show that the ability of metal sulfate decomposition can be ordered as follows (from easy to difficult): FeSO4, In2(SO4)3, Fe2(SO4)3, ZnSO4, PbSO4. The phase transition and decomposition temperatures from thermodynamic calculation are consistent with TG-DSC results. The calculated temperatures are lower than those from TG-DSC, and the difference is from 7.5 to 283.1 K. The sulfates in zinc leaching residue and iron sinking slag will decompose more thoroughly when the furnace temperature is above 1316.1 K.
Key words: smelting slag; metal sulfates; bath smelting; thermodynamic calculation
