(中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083)
摘 要: 針對硫酸錳電解液中氯離子不斷積累并損害電解過程的問題，查閱錳、鋅等金屬電解液中氟氯的脫除方法并對主要方法進行了歸納總結(jié)，結(jié)合各方法的優(yōu)缺點，提出硫酸氧鉍作為除氯劑的沉淀除氯新方法，包括“活化-沉淀-再生”三個主要方面，對工藝過程進行了研究。結(jié)果表明：在pH=1、溫度30 ℃、過量系數(shù)1.5、反應(yīng)時間1 h的條件下，除氯過程的除氯效率達到95.11%，沉淀物主要物相為BiOCl且結(jié)晶度良好，處理后液中含氯離子43.96 mg/L，含鉍離子110.00 mg/L；再生除氯劑的除氯效率達90.75%，除氯后液含氯降至83.00 mg/L；在除氯后液的深度凈化除鉍過程中，鉍的置換沉淀率可達98.46%，置換后液中含鉍1.80 mg/L；最終所得溶液可滿足錳電解要求。
關(guān)鍵字: 錳電解液；硫酸氧鉍；氯氧鉍；除氯；活化；再生
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:A new method of removing Cl- as BiOCl by precipitation was proposed to weaken the negative effect during Mn electrolytic deposition which was taken by Cl-, after reviewing and summarizing relevant references. The new method can be divided into three steps: transforming Bi2O3 to (BiO)2SO4, removing Cl- by precipitation and regeneration. The results show that (BiO)2SO4 is the most ideal Cl- removal agent and the process of boiling in sulfuric acid is necessary. In precipitation, the factors of pH, temperature, excess coefficient and duration time affect the results significantly. Moreover, decreasing pH can dramatically drive the reaction of Cl- removing. The Cl- concentration decreases from 900.00 mg/L to 43.96 mg/L and the Cl- removal rate reaches 95.11% under the optimal condition experiment, and the Cl removal precipitate consists of BiOCl mainly. In regeneration process, BiOCl can be transferred to (BiO)2SO4 by boiling in hot sulfuric acid, and the Cl- removal rate can reach 90.78% when the regeneration removal agent is used. The concentration of remined Bi3+ in Cl- removal solution is declined to 1.80 mg/L by cemented using Mn powders and the cementation rate reaches 98.46%.
Key words: manganese electrolyte; (BiO)2SO4; BiOCl; Cl removal; activation; regeneration
