Nuclear Chemistry and Industrial Materials Recycling, Department of Chemical and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden.
Nuclear Chemistry and Industrial Materials Recycling, Department of Chemical and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden.
Waste Manag. 2015 Feb;36:289-96. doi: 10.1016/j.wasman.2014.10.023. Epub 2014 Nov 28.
With the rising popularity of fluorescent lighting, simple and efficient methods for the decontamination of discarded lamps are needed. Due to their mercury content end-of-life fluorescent lamps are classified as hazardous waste, requiring special treatment for disposal. A simple wet-based decontamination process is required, especially for streams where thermal desorption, a commonly used but energy demanding method, cannot be applied. In this study the potential of a wet-based process using iodine in potassium iodide solution was studied for the recovery of mercury from fluorescent lamp waste. The influence of the leaching agent's concentration and solid/liquid ratio on the decontamination efficiency was investigated. The leaching behaviour of mercury was studied over time, as well as its recovery from the obtained leachates by means of anion exchange, reduction, and solvent extraction. Dissolution of more than 90% of the contained mercury was achieved using 0.025/0.05 M I2/KI solution at 21 °C for two hours. The efficiency of the process increased with an increase in leachant concentration. 97.3 ± 0.6% of the mercury contained was dissolved at 21 °C, in two hours, using a 0.25/0.5M I2/KI solution and a solid to liquid ratio of 10% w/v. Iodine and mercury can be efficiently removed from the leachates using Dowex 1X8 anion exchange resin or reducing agents such as sodium hydrosulphite, allowing the disposal of the obtained solution as non-hazardous industrial wastewater. The extractant CyMe4BTBP showed good removal of mercury, with an extraction efficiency of 97.5 ± 0.7% being achieved in a single stage. Better removal of mercury was achieved in a single stage using the extractants Cyanex 302 and Cyanex 923 in kerosene, respectively.
随着荧光灯的普及，需要简单高效的方法来处理废弃的灯管。由于含汞量，报废的荧光灯被归类为危险废物，需要特殊处理。因此需要一种简单的湿法去污工艺，特别是对于那些不能应用热解吸（一种常用但耗能高的方法）的水流。在这项研究中，研究了在碘化钾溶液中使用碘的湿法工艺，以从荧光灯废物中回收汞。研究了浸出剂浓度和固液比对去污效率的影响。研究了汞的浸出行为随时间的变化，以及通过阴离子交换、还原和溶剂萃取从所得浸出液中回收汞的情况。在 21°C 下，使用 0.025/0.05 M I2/KI 溶液，两小时后，超过 90%的汞被溶解。随着浸出剂浓度的增加，该过程的效率也随之提高。在 21°C 下，两小时内，使用 0.25/0.5 M I2/KI 溶液和固液比为 10%（w/v），可溶解 97.3±0.6%的汞。碘和汞可以用 Dowex 1X8 阴离子交换树脂或连二亚硫酸钠等还原剂从浸出液中有效去除，使所得溶液可作为非危险工业废水处理。萃取剂 CyMe4BTBP 对汞的去除效果良好，在单级萃取中，萃取效率达到 97.5±0.7%。在煤油中使用萃取剂 Cyanex 302 和 Cyanex 923 可分别实现对汞的更好去除，萃取效率分别为 95.0±0.5%和 94.4±0.5%。
