(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長沙 410083)
摘 要: 針對堿式碳酸鋅(2ZnCO3·3Zn(OH)2)在L-谷氨酸一鈉溶液中的熱力學(xué)行為，根據(jù)配位化學(xué)理論繪制谷氨酸根(Glu2−)和碳酸根(CO32−)在溶液中的形態(tài)分布圖；根據(jù)雙平衡法理論研究Zn(Ⅱ)-Glu2−-CO32−-H2O體系中Zn(Ⅱ)的配合平衡熱力學(xué)，并繪制L-谷氨酸一鈉濃度在0~5 mol/L范圍和pH在7~14范圍內(nèi)變化時(shí)的熱力學(xué)平衡圖，研究L-谷氨酸一鈉濃度、pH值和游離碳酸根離子濃度對L-谷氨酸一鈉浸出堿式碳酸鋅的影響。同時(shí)對熱力學(xué)計(jì)算結(jié)果進(jìn)行實(shí)驗(yàn)驗(yàn)證。結(jié)果表明：在一定的L-谷氨酸一鈉濃度下，當(dāng)pH=10時(shí)，溶液中總鋅濃度達(dá)到最大值；鋅離子濃度理論計(jì)算值與實(shí)驗(yàn)值之間相對誤差的絕對平均值為11.39%。
關(guān)鍵字: L-谷氨酸一鈉；堿式碳酸鋅；浸出；熱力學(xué)
Zn(Ⅱ)-Glu2−-CO32−-H2O system
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:Thermodynamic behaviors of basic zinc carbonate(2ZnCO3·3Zn(OH)2) with L-monosodium glutamate solution were studied. Species distribution diagrams of glutamate (Glu2−) and carbonate ion(CO32−) in the solution were obtained based on the coordination chemistry theory. Thermodynamics of Zn(Ⅱ) complex equilibrium in the system of Zn(Ⅱ)-Glu2−-CO32−-H2O were studied based on the double equilibrium theory. When the concentration of L-monosodium glutamate and pH value varied accordingly in ranges of 0−5 mol/L and 7−14, the equilibrium thermodynamic diagrams were constructed, and the effects of L-monosodium glutamate concentration, pH value and free carbonate ion concentration on leaching of basic zinc carbonate were also studied. The results show that the total zinc concentration reaches the maximum value when the pH value is 10 under a certain L-monosodium glutamate concentration. The absolute average value of relative error between the theoretical calculation and experimental results is 11.39%.
Key words: L-monosodium glutamate; basic zinc carbonate; leaching; thermodynamic
