(中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083)
摘 要: 針對(duì)貴州地區(qū)復(fù)雜鎳鉬礦難以清潔高效利用的問題，提出了堿性焙燒-凈化-冷凍結(jié)晶-離子交換回收鉬及副產(chǎn)物Na2SO4的清潔冶金工藝。采用單因素實(shí)驗(yàn)法，考察了堿性焙燒-浸出過程中Na2CO3用量、焙燒溫度、焙燒時(shí)間、浸出溫度和浸出時(shí)間等因素對(duì)鉬浸出率和浸出液成分的影響，研究了冷凍結(jié)晶過程溶液中鉬、硫含量對(duì)Na2SO4結(jié)晶率及產(chǎn)品純度的影響。結(jié)果表明：在Na2CO3用量為理論用量的1.2倍、焙燒溫度800 ℃、焙燒時(shí)間1 h、浸出溫度95 ℃、浸出時(shí)間1 h的優(yōu)化條件下，鉬的總浸出率為94.68%。經(jīng)四次循環(huán)后，浸出液中鉬濃度約為40 g/L、硫濃度約為90 g/L。對(duì)循環(huán)浸出液冷凍結(jié)晶，可得到結(jié)晶率為89.61%的Na2SO4。結(jié)晶母液經(jīng)離子交換得到的高峰解析液中鉬濃度可達(dá)115 g/L以上。
關(guān)鍵字: 鎳鉬礦；清潔冶金；冷凍結(jié)晶；Na2SO4回收；鉬回收
（School of Metallurgy and Environmental, Central South University, Changsha 410083, China）
Abstract:The Ni-Mo ore is a kind of refractory ore, which has been neglected for several decades, due to the absence of an efficient treatment process. In this paper, a metallurgy process including alkaline roasting, purification, freezing crystallization, and ion exchange for extraction of molybdenum and Na2SO4 from Ni-Mo ore has been proposed. The effects of Na2CO3 dosage, roasting temperature, roasting duration, leaching temperature and leaching duration on the leaching efficiency of molybdenum and the composition of the leachate were investigated by single-factor experiment. In addition, the effects of the concentration of molybdenum and sulfur in the leachate on the crystallization efficiency and purity of Na2SO4 were studied. The result shows the leaching efficiency of molybdenum is 94.68% with the optimal conditions in roasting-leaching process of the dosage of Na2CO3 is 1.2 times of the theoretical amount, the roasting temperature of 800 ℃, the roasting duration of 1 h, and the leaching temperature of 95 ℃. The purity of Na2SO4 produced by freezing crystallization process is 97.45% with the optimum condition of the concentration of molybdenum about 40 g/L and sulfur about 90 g/L. The concentration of molybdenum in stripping aqueous is 115 g/L, which is obtained by ion exchange.
Key words: Ni-Mo ore; clean metallurgy; freezing crystallization; Na2SO4 recovery; molybdenum recovery
