Rapid and green process for valuable materials recovery from waste liquid crystal displays

Authors：Cui, Jiaying; Zhu, Nengwu^*; Li, Yao; Luo, Deliang; Wu, Pingxiao; Dang, Zhi

Source：RESOURCES CONSERVATION AND RECYCLING, 2020, 153: 104544.

DOI：10.1016/j.resconrec.2019.104544

• Waste LCDs
• Materials recovery
• Indium
• Aspergillus niger
• Leaching
• Optimization

The current researches on the recycling of waste liquid crystal displays (LCDs) are hard to widely industrialize that require low-cost, rapid and green technologies. In this study, we shortened the acetone soaking time from at least 20 h to 30 min to separate polarizer. In addition, indium bioleaching using Aspergillus niger (A. niger) was firstly explored. The efficiency of indium bioleaching from fermentation broth could reach 100% within 90 min at 70 degrees C, and the glass residues could be reused. Oxalic acid showed excellent abilities on indium bioleaching process according to the analysis of Fourier transform infrared spectroscopy and kinetics. Furthermore, the leaching parameters of low-concentration oxalic acid solution were optimized using response surface method to improve the powder dosage from 10 to 150 g/L. Therefore, this research promoted bioleaching technology development using A. niger and formed a sustainable process in industry for the recovery of valuable materials from waste LCDs.