The Availability of Indium: The Present, Medium Term, and Long Term

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This report is available at no cost from the National Renewable Energy Laboratory (NREL) at 

manufacturers. Assuming that most LCD/flat-panel display manufacturers now recycle 

manufacturing waste implies primary indium demand of ~730 tonnes and the successful 

deposition of ~400 tonnes, of which ~220 tonnes is from primary indium and ~180 tonnes is 

from new scrap recycling. The amount generated by new scrap recycling reduced primary 

indium demand by 608.5 tonnes (Appendix B reports these figures in detail). 

When considering the cost of secondary supply, we note that before 1996, recycling was not a 

significant source of supply. Before 1995, indium prices were $125–$200/kg. Increased demand 

caused prices to increase significantly in 1995 and 1996 to a peak of almost $600/kg. This surge 

led manufacturers to rationalize their use of indium and incentivized producers to reclaim indium 

waste. These factors simultaneously increased supply, decreased demand, and together with 

other factors, resulted in reduced prices. Once prices relaxed, recycling of indium continued. 

The response of secondary production to price fluctuations suggests that, in the medium term, 

indium prices higher than $300–$400/kg are required to increase new scrap secondary 

production capacity. Once the capacity is installed, producers can profitably recycle indium at 

prices higher than about $175/kg. With this in mind, we use a short-term production cost for 

secondary production of $175/kg and a medium-term cost of $350/kg in our analysis. 

3.7.3  Recycling From End-of-Life Products 

In addition to the recovery of indium from manufacturing waste, much research has been 

conducted into the secondary recovery of indium from consumer waste. According to Roskill 

(2010), a proprietary technique has been jointly developed between Sharp and Aqua Tech Co. to 

recycle indium from LCD panels. The recycling process can be broadly described as comprising 

two stages: (1) comminution, where consumer waste products are reduced into fine pieces; and 

(2) recovery by chemical leaching or vaporization.  


In Sharp and Aqua’s recycling process, high-purity indium can be recovered from a process that 

uses only common chemicals, thereby eliminating the need for possible high-cost energy 

resulting from a process dependent on high temperatures or pressures (Sharp Electronics UK 

2012). The companies are continuing large-scale prototype studies to establish the viability of the 

technique to operate as a closed-loop recycling system.  

As an additional example, Figure 14 depicts a process to recover indium from the LCDs of 

discarded cellular phones as described by Takahashi et al. (2009). The process is similar to that 

used by Sharp/Aqua in that it can broadly be split into the same two-step process of comminution 

and chemical concentration. In this proposed process, indium is recovered from discarded 

cellular phones through chloride-induced vaporization. Following the comminution stage, sieved 

material from discarded cell phones is treated with a solution of hydrochloric acid (HCl), which 

alters the structure of the indium oxide and allows it to be vaporized at relatively low 

temperature. Next, the vaporized indium compound is condensed on a cooled surface and 

recovered. Takahashi et al. report that 84% of indium contained in LCDs is recovered.  



This report is available at no cost from the National Renewable Energy Laboratory (NREL) at 


Figure 14. An example of recycling LCDs from discarded mobile phones using vaporization 

(Takahashi et al. 2009) 


Secondary production of indium from consumer waste is not a material source of supply because 

less than 1% of indium contained in EOL products is recycled (Buchert et al. 2012). A key issue 

for consideration in the recycling of indium from consumer waste is the interaction between the 

value of the recycled material and the degree of dispersion of the raw material. A greater degree 

of dispersion implies that the cost of collecting, sorting, recycling, and refining is likely to be 

higher than if the raw material were concentrated within a single product at a single location and 

in large quantities. These costs are then compared to the value of the material that can be 

recovered to ascertain whether its recycling is economic. As discussed by Dahmus and Gutowski 

(2007), certain products, such as catalytic convertors, automobiles, and batteries, are economic to 

recycle. Other items such as computers, televisions, cell phones, and small electronic items fall 

beneath an apparent recycling boundary. 

Although the recycling of indium from EOL products has significant potential, old scrap is not 

currently a significant source. The low recycling rate implies that the costs of collecting, sorting, 

and refining such scrap (because of the highly dissipative use of indium in consumer products) 

are still higher than long-term indium price expectations. In addition, dedicated recycling from 

concentrated sources of indium such as EOL solar panels is a supply source reserved for the 

future because the average solar panel has a life expectancy of approximately 20 years and 

recyclers are hesitant to commit capital to dedicated facilities until they can be assured that the 

base loads of plant feed are available (Van den Broeck 2010). Thus, because of its low contribu-

tion and high costs, we exclude consumer waste as a source of indium in our short-term analysis. 

3.8  Total Primary and Secondary Production 

In summary, indium primary production was approximately 770 tonnes in 2013 (Tolcin 2014a). 

Production is relatively concentrated, with about half currently in China. Since the indium price 

increases in 1995 and 1996, secondary production has been a significant contributor to overall 

supply, reducing primary indium demand by approximately 609 tonnes in 2013. Significant 

secondary supply of approximately 610 tonnes principally takes place close to high-tech 

manufacturing centers such as Japan (59%, 300 tonnes), South Korea (7%, 36 tonnes), and China 

Liquid Crystal Display (LCD)



Heat treatment




HCl treatment


Vaporization of 


Vaporization of In


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