Degradation process regulation of waste LCD panel to ensure the remain of indium in solid phase by hydrothermal reaction.

Graphical abstract Highlights • Hydrothermal reaction can realize effective degradation of organic materials in LCD panel. • The loss of indium occurs in hydrothermal environment with the prolongation of reaction time. • Parameter regulation can achieve degradation of organic materials and retention of indium in solid phase. • The degradation ratio of organic materials is close to 90% under optimal pretreatment conditions. Abstract The environmental risks and recycling potential of organic materials and indium of waste LCD panel has produced commercial value. It has been found that hydrothermal reaction can achieve an efficient and clean degradation of organic materials in a closed environment. However, as the degradation process occurs, the glass substrate is gradually exposed to the hydrothermal environment. Whether the metal indium is dissolved into the liquid phase and whether it affects product quality and the subsequent leaching process need to be discussed. In present study, simultaneous organic materials degradation and pretreatment of indium recycling was achieved due to the regulation of parameters. Effects of reaction temperature, reaction time, H 2 O 2 supply and pH of the reaction solution on the transfer of indium in liquid and solid phase were investigated. The results showed that the degradation rate of the organic material reach 90% under the neutral condition of 300℃ of reaction temperature, 36 mL of water and 7.2 mL of H 2 O 2 supply and 11 min of reaction time. This pretreatment method effectively realized the resource recovery of waste LCD panel and the outflow of metal indium was inhibited at the same time, thus further comprehensive recycling of resources could be prepared. [ABSTRACT FROM AUTHOR]