次氧化锌浸取净化新工艺

研究了以炼铅厂含锌烟灰为原料，经盐酸浸取、高锰酸钾氧化、锌粉置换制备氯化锌溶液的工艺。以锌的浸出率最高，杂质铅的浸出率最低，铁、锰、铅、镉、铜脱除最彻底为目标，实验得出最佳的酸浸和净化条件：40 g次氧化锌、71 mL浓盐酸、130 mL水在30 ℃下浸取50 min后，过滤，洗涤滤渣，滤液定容为250 mL，取200 mL滤液，滤液中加高锰酸钾0.013 6 g，10 ℃下氧化2 h后过滤，取200 mL二次滤液向其中加锌粉0.12 g，40 ℃下反应50 min后过滤，得浓度为1.63 mol/L的氯化锌溶液。在上述工艺条件下，锌的浸出率为94.2%，氯化锌溶液中杂质离子含量满足HG/T 2323-2012《工业氯化锌》中优等品的要求，可用来生产符合GB/T 19589-2004《纳米氧化锌》规定的Ⅰ类纳米氧化锌。

New technology for extraction and purification of secondary zinc oxide

A new technology of preparing zinc chloride solution with zinc-containing ash from lead-smelting factory as raw material was studied.According to the technology，zinc chloride solution could be prepared through hydrochloric acid leaching，potassium permanganate oxidation，and zinc powder replacement.To get the highest leaching rate of zinc，the lowest leaching rate of impurity Pb，and thoroughly removing Fe，Mn，Pb，Cd，and Cu elements，the optimum experimental acid leaching and purification conditions were obtained as follows：After 40 g secondary zinc oxide，71 mL concentrated  hydrochloric acid，and 130 mL water reacting together for 50 min at 30 ℃，filtrating，and washing the filter residue.Then the filtration was diluted to 250 mL constant volume.Adding 0.013 6 g KMnO4 into the 200 mL filtration，and filtrating after oxidating at 10 ℃ for 2 h. Adding Zn powder 0.12 g into the 200 mL secondary filtration，filtrating after reacting for 50 min at 40 ℃ and the zinc chloride solution with 1.63 mol/L was obtained.Under above conditions，the leaching rate of zinc was 94.2%，the impurity ion content in zinc chloride solution met the requirements of high-class zinc chloride products of Industrial Zinc Chloride（HG/T 2323-2012） and could be used for the production of level 1 nanometer zinc oxide stipulated in provisions of Nanometer Zinc Oxide（GB/T 19589-2004）.