(江西理工大學(xué) 冶金與化學(xué)工程學(xué)院，贛州 341000)
摘 要: 提出將抗壞血酸應(yīng)用到離子吸附型稀土礦的浸取過程，通過其與稀土的絡(luò)合作用來強(qiáng)化離子相稀土的浸取，降低浸取劑用量，減少氨氮污染；同時(shí)，利用抗壞血酸的還原性質(zhì)浸取離子吸附型稀土礦中的膠態(tài)相稀土，提高稀土資源利用率。以硫酸銨-抗壞血酸為復(fù)合浸取劑，對(duì)不同浸取條件下稀土及鐵鋁雜質(zhì)的浸出行為進(jìn)行研究。結(jié)果表明：在最佳浸取條件下，即硫酸銨濃度0.15 mol/L、抗壞血酸濃度為1.0 g/L、浸取劑pH為2.5、浸取劑體積為200 mL、注液速度為0.80 mL/min時(shí)，稀土浸出率達(dá)102.2%，鈰配分為5.37%，浸出液中鐵和鋁的濃度分別為20.91 mg/L和23.74 mg/L。此外，復(fù)合浸取體系中離子相稀土的浸出率為98.7%，較單獨(dú)硫酸銨浸取體系提高2.7%，其在浸取尾礦中的含量?jī)H為2×10-5；而膠態(tài)相稀土的浸出率達(dá)42.9%，其在尾礦中的含量為8×10-5。離子吸附型稀土礦抗壞血酸強(qiáng)化-還原浸取技術(shù)具有有效提高稀土資源利用率和減少環(huán)境氨氮污染的雙重優(yōu)勢(shì)，對(duì)離子吸附型稀土礦高效綠色開發(fā)及其健康可持續(xù)發(fā)展具有重要推動(dòng)作用。
關(guān)鍵字: 離子吸附型稀土礦；抗壞血酸；強(qiáng)化；還原；膠態(tài)相稀土
（School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:The application of ascorbic acid to the leaching process of the ion-adsorption type rare earths ore was proposed. The ascorbic acid can form a stable coordination with rare earth ions, so that it would intense the leaching of ion-exchangeable phase rare earth, resulting in the decrease of the leaching agent dosage and ammonia nitrogen pollution. Moreover, the ascorbic acid has a strong reductive property, it can leach the colloidal sediment phase rare earth, improve the utilization of the rare earth resources. The ammonium sulfate and ascorbic acid were used as a compound leaching agent, the leaching behaviors of rare earth and Fe/Al impurities under different leaching conditions were studied. The results show that 102.2% of the total rare earth leaching efficiency and 5.37% Ce partition are achieved under the optimum leaching condition in a flow rate of 0.80 mL/min, initial pH of 2.5, leaching agent of 200 mL, ammonium sulfate of 0.15 mol/L and ascorbic acid of 1.0 g/L in the leaching agent. The concentration of Al is 23.74 mg/L and the concentration of Fe is 20.91 mg/L in the leaching liquor. Additionally, in the ammonium sulfate-ascorbic acid compound leaching system, the leaching efficiency of ions-exchangeable phase rare earth is 98.7%, which is 2.7% higher than that in the ammonium sulfate leaching system, and the content of the ion-exchangeable phase rare earth in the leaching tailings is only 2×10-5. The leaching efficiency of colloidal sediment phase rare earth is about 42.9% and the colloidal sediment phase rare earth is 6×10-5 in the leaching tailings. The intensification-reduction leaching technology of the ion-adsorption type rare earths ore with ascorbic acid has the dual advantages of improving the utilization of rare earth resources and the reduction of ammonia nitrogen pollution. It plays an important role in the efficient-green development of the ion-adsorption type rare earths ore and their healthy and sustainable development.
Key words: ion-adsorption type rare earths ore; ascorbic acid; intensification; reduction; colloidal sediment phase rare earth
