(1. 龍巖學(xué)院 化學(xué)與材料學(xué)院，龍巖 364012；
2. 中南大學(xué) 冶金與環(huán)境學(xué)院，長(zhǎng)沙 410083；
3. 福州大學(xué) 紫金礦業(yè)學(xué)院，福州 350108)
摘 要: 采用“焙燒-硫酸浸出-中和沉淀”工藝提取明礬石精礦中的鎵，獲得含Ga 0.1%以上的鎵精礦。為了實(shí)現(xiàn)鎵精礦的高值化利用，提出“堿浸-離子交換-溶液凈化-電積”回收鎵精礦中金屬鎵的工藝，對(duì)最佳工藝條件進(jìn)行研究。在最佳工藝條件下，鎵精礦中Ga的堿浸浸出率達(dá)98.46%；離子交換實(shí)驗(yàn)表明，采用D5240樹(shù)脂可以有效地富集鎵，但雜質(zhì)釩也得到富集，樹(shù)脂解吸液中含鎵2.1g/L，釩0.23g/L；在pH=12的條件下，可通過(guò)鈣鹽法除釩，當(dāng)解吸液中Ca2+添加量為0.02 mol/L時(shí)，釩濃度降至1.45 mg/L；鎵電積過(guò)程中電流效率呈現(xiàn)先增大后減小的趨勢(shì)，當(dāng)電積時(shí)間為2h時(shí)，電流效率達(dá)到峰值4.3%；隨著電積液中NaOH濃度的升高，陰極表面形貌由粗糙變得光滑。當(dāng)NaOH濃度為200g/L時(shí)，陰極表面平整光滑，可獲得99.94%金屬鎵。
關(guān)鍵字: 鎵精礦；堿浸；離子交換；鈣鹽沉淀；鎵電積
（1. School of Chemistry and Materials, Longyan University, Longyan 364012, China;
2. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
3. College of Zijin Mining, Fuzhou University, Fuzhou 350108, China）
Abstract:A gallium concentrate with more than 0.1% Ga can be obtained by “roasting-sulfuric acid leaching-and precipitation” process from alunite concentrate. In order to realize the high value utilization of gallium concentrate, the technology of recovering metal gallium by “alkali leaching-ion exchange-solution purification-electrowinning” was proposed, and the optimum technological conditions were studied. Under the optimum conditions, the leaching rate of Ga in gallium concentrates reaches 98.46%. The ion exchange experiment shows that the D5240 resin can effectively enrich Ga, but the impurity vanadium is also enriched. The desorption solution contains gallium 2.1 g/L and vanadium 0.23 g/L. Vanadium can be removed by the calcium salt method under the condition of pH=12. When the Ca2+ additive amount is 0.02 mol/L, the vanadium concentration is reduced to 1.45 mg/L. The current efficiency in gallium electrodeposits increases firstly and then decreases. When the electrodeposition time is 2 h, the current efficiency reaches 4.3% of the peak value. With the increase of NaOH concentration in the electrodeposition electrolyte, the cathode surface is from coarse to smooth. Finally, the purity of 99.94% metallic gallium is obtained.
Key words: gallium concentrate; alkaline leaching; ion exchange; calcium salt precipitation; gallium electrowinning
