Abstract
Indium is one of the strategically important materials, which have been characterized as critical by various industrialized countries. Despite its high relevance, only low recycling rates are realized. Its main application is in indium tin oxide (ITO), which is used in the production of liquid crystal displays (LCD). However, recovery strategies for indium from LCDs are not yet being implemented in recycling practices. Although LCDs consist of a sandwich compound with additional materials such as glass (80% ± 5%) and polarizer foils (20% ± 5%), recently published recycling approaches focus mainly on the recovery of indium exclusively. This study, first of all, provides information about the quantity and quality of the materials applied in the LCD panels of the various equipment types investigated, such as notebooks, tablets, mobile phones, smartphones, PC monitors, and LCD TVs. The highest indium mass fraction per mass of LCD was determined in mobile phones and the least indium was found in smartphones. Additionally, we found the significant use of contaminating metals like antimony, arsenic, lead, and strontium in the glass fraction. Thus, specific recovery strategies should focus on selected equipment types with the highest indium potential, which is directly related to the sales of new devices and the number of collected end-of-life devices. Secondly, we have developed and successfully tested a novel recycling approach for separating the sandwich compound to provide single output fractions of panel glass, polarizer foils, and an indium concentrate for subsequent recycling. Unfortunately, the strongly varying content of contaminating metals jeopardizes the recycling of this output fraction. Nonetheless, economic recycling approaches need to address all materials contained, in particular those with the highest share in LCD panels such as polarizer foils and panel glass.
Highlights
Indium is one of the strategically important materials that have been characterized as critical by several industrialized countries [1,2,3,4]
Over 55% of the worldwide production of indium is used in the indium tin oxide (ITO) target industry, which is a major component in the production of liquid crystal displays (LCD) [5,6,7,8]
The highest indium mass fraction was determined in LCD panels from mobile phones and the least indium was found in LCD panels from smartphones
Summary
Indium is one of the strategically important materials that have been characterized as critical by several industrialized countries [1,2,3,4]. The output of refined indium increased to 800 t in 2013 and 820 t in 2014 [6]. Over 55% of the worldwide production of indium is used in the ITO (indium tin oxide) target industry, which is a major component in the production of liquid crystal displays (LCD) [5,6,7,8] (cf Figure 1). Based on the screen size and the primary function of the device, the shares of the applied LCD. BasedOur on the size andoperations the primary function of the device, the shares applied of panels vary. Ownscreen disassembly revealed mass shares of LCD panelsofinthe notebooks ownphones disassembly operations mass shares
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
