In the past, the pretreatment and indium extracting were conducted in independent disposal system to recycle indium from waste liquid crystal display (LCD), which make the recycling process inefficient and costly. In this study, an efficient and environmental friendly indium recycling process was proposed by an in-situ reaction process. The carbon residue generated in the pretreatment stage (organic removing stage) was used as the reductant to extract indium in the same reaction system. Comparison results indicated that the reaction effects of pyrolytic carbon were much better than coke since the structure of pyrolytic carbon is porous which would make the reactants contact better, and promote the reaction efficiency. Futhermore, results showed that the pyrolytic carbon was sufficient for the indium reduction without adding extra reductant, and indium conversion rate can reach 99.08% under the condition of 935 °C, 5 Pa, 2.5 wt%, 30 min, <0.3 mm. In this study, the organic pollutants were removed, while the indium also could be recycled in a closed-loop system. To sum up, this study could simplify the process route of waste LCD recycling, and provide fundamental basis as well as practical experience for recycling waste LCD environmentally and efficiently.
Improper treatment of spent lithium ion batteries will cause great damages to environment. Vacuum reduction was advised as a green recovery technology of nickel and cobalt from spent lithium ion batteries. However, the separation of magnetic particles from the vacuum-reduced products of spent lithium-ion batteries has not been studied. After reduction, the particle size was so small that the formation of agglomerates would affect the separation efficiency which was a common problem in fine magnetic particle sorting. In this paper, a fluid-magnetic separation method was developed for micro-separation of cobalt from the vacuum reduction product of electrode materials of spent lithium ion batteries. This method had a high level of clean production and sustainable development at the same time as high separation rate. An energy model was established to analyze the mechanism of breaking agglomerates, and the experimental parameters affecting recovery efficiency were studied according to the energy model. In simulation experiments, under the optimal parameter conditions of 35 °C, solid-liquid ratio of 500 mL/g and collection mat material of plastic, the recovery rate and purity of cobalt micro-particles were both above 99%. After applying the vacuum reduction product to fluid-magnetic separation, the recovery rate of magnetic fine particles was 98.26%, which fully verified the effectiveness. Further, it provides a new idea for separating micro magnetic particles from micro-sized mixed particles and promoted the process of recycling spent lithium ion batteries.
危险品化学品经营许可证（带存储）