利用硝酸型退锡废液回收锡单质的研究

摘要

研究一种清洁、低能耗、无副产物排放的从印制电路板硝酸型退锡废液中回收锡单质的方法。通过用絮凝剂、过滤方法得到锡酸沉淀;在高温条件下锡泥与浓盐酸反应生成锡离子,用还原剂将其中的锡离子还原成单质锡。最佳的反应条件为：100 ml退锡废液的絮凝剂及用量是5%聚丙烯酰胺14 ml;10 g锡酸的最佳浓盐酸用量40 ml,油浴温度140℃;最佳还原剂硼氢化钾的浓度1.2 mol/L,反应时间30 min。通过XRD表征,证实所制备的为锡单质。%This paper focuses on a kind of clean,low energy consumption,no by-product emissions method from tin wastewater from printed circuit board.By using flocculants and filter to get the tin acid;Tin acid with concentrated hydrochloric acid to reaction of tin ions in high temperature conditions,reduced to elemental tin from tin ions with the reducing agent.The optimal reaction condition is: the best flocculants amount of 100mL is polyacrylamide amount of 14mL,the optimum of concentration of hydrochloric to dissolve 10g tin acid is 40mL,oil bath temperature is 140℃,the best reducing agent of potassium borohydride concentration is 1.2mol/L,reaction time is 30min.Characterized by XRD,confirmed the prepared is elemental tin.