从净化含银废水的水生植物残体中提取和回收白银

THE EXTRACTION AND RECLAMATION OF SILVER FROM BEARING SILVER WASTEWATER BY RESIDUE OF AQUATIC PLANT

本文介绍了从凤眼莲等水生植物体中回收废水中白银的方法.第一种方法是将植物残体直接打捞、晒干、灰化、HNO_3浸取,氯化法沉淀直至火法冶炼(加入碳酸钠和硼砂)出银;第二种方法是将植物残体全部集中,晒干,最后由贵稀金属提炼厂专门处理.根据上述方法已成功地从净化含银废水的水生植物残体中提炼和回收白银561.7g.

The reclamation of silver in waste water by aquatic plants such as water hyacinth had been studied during 1988 to 1989.The first method can be briefly shown as following: collecting plant residue, drying in the sun, ashing, extracting with HNO3, precipitating with chloride, refining with sodium carbonate and borax, tapping silver . The second involves all the dried plant residua i n the sun, and then are sent to a precious metal extracting factory for special treatment.Practically, the above methods have been proved to be feasible and 561.7 g silver has been successfully extracted and retrieved from silver -bearing waste water by aquatic plant with the first and the second methods.