(中南大學(xué) 冶金與環(huán)境學(xué)院，長沙 410083)
摘 要: 銅陽極泥經(jīng)低溫堿性熔煉-浸出處理后，鉛、砷、硒等進(jìn)入強(qiáng)堿性浸出液，其中鉛和砷分別以Pb(OH)n2-n和AsO43-形式存在。為分離其中的鉛、砷等主要雜質(zhì)元素，通過計(jì)算PbS-H2O體系電勢-pH圖、Ca-As-H2O體系溶解平衡濃度-pH圖后，采用硫化沉淀和鈣鹽沉淀的方式有效去除鉛、砷，同時(shí)保證硒的低分散度。實(shí)驗(yàn)結(jié)果表明：采用硫化沉淀，硫化鈉過量系數(shù)2.5，反應(yīng)溫度20 ℃，反應(yīng)時(shí)間15 min。在此條件下，鉛和銅沉淀率都達(dá)到99.99%以上，硒損失5%；采用鈣鹽沉淀，控制溶液pH=10，鈣砷比3.5，反應(yīng)溫度90 ℃，反應(yīng)時(shí)間1.5 h。在此條件下，砷沉淀率達(dá)到99%以上，硒沉淀率為2.81%。
關(guān)鍵字: 銅陽極泥；浸出液；硒；硫化鉛；砷酸鈣
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:The leaching solution of low-temperature alkaline smelting-leaching process contains selenium, arsenic and lead, which exist in forms of SeO42-, Pb(OH)n2-n and AsO43-, respectively. In order to recover selenium, it is necessary to fully precipitate the lead and arsenic. After calculating the potential-pH diagram of PbS-H2O system and the solubility-pH diagram of Ca-As-H2O system, the lead and arsenic were removed by the sulfurized precipitation and calcified precipitation progress, while ensured the low dispersion of selenium. The results show that the lead can be effectively separated from other metals under the optimum conditions which are stoichiometric requirement of Na2S of 2.5, reaction temperature of 20 ℃, reaction time of 15 min. The copper and lead precipitation can reach 99.99% when the arsenic and selenium precipitation rate is less than 5%. The arsenic precipitation ratio reaches 99% when the reaction conditions are pH=10, n(Ca)/n(As)=3.5, bath temperature of 90 ℃ and reaction time of 1.5 h.
Key words: copper anode slime; leaching solution; selenium; lead sulfide; calcium arsenate
