End-of-life CIGS photovoltaic modules secondary resource
Discarded copper-indium-gallium-selenide (CIGS) thin-film photovoltaic modules and their separated coated-glass fractions are a composite secondary resource. The curated study explicitly describes end-of-life Q-Smart panels supplied by Polyeco S.A. This scope excludes crystalline-silicon and CdTe modules, sputtering targets, production-chamber scrap, and factory-supplied cells without documented end-of-life provenance. The resource is distinct from its constituent elements and from a pure CIGS compound or mineral species. Constituent criticality designations are not inherited.
Microbial & Biochemical Mechanisms (1)
Chemical leaching of metals from thermally separated CIGS-coated glass
recycling
Laboratory acid treatment transfers indium, gallium and other metals from separated CIGS-coated glass to solution. This is an abiotic thermal and hydrometallurgical treatment. Measured leachate concentrations establish dissolution under the tested conditions, not a closed whole-module recovery yield or a purified final product.
Experimental Context & Analytical Limits:
Theocharis et al. (2021), Sections 2.1–2.5 and 3.1–3.2: source-described end-of-life Q-Smart panels were dismantled and thermally treated, then manually separated into clear glass, coated glass and ash; ribbons and polymer films were removed. The abstract specifies 550 degrees C for 15 minutes in excess air, while Section 2.3 describes membrane decomposition at 540–550 degrees C. Its parenthetical 1500 degrees C refers to the laboratory furnace specification, not the adopted sample treatment. Approximately 1.5-by-1.5 cm coated-glass pieces were leached. Tests compared 6 N nitric, hydrochloric and sulfuric acids at ambient temperature and a reported solid/liquid ratio of 30%, with a further hydrochloric-acid test at 80 degrees C. Nitric-acid concentrations of 1, 3 and 6 N were tested at reported solid/liquid ratios of 50% and 70%; the percentage basis is not defined. The authors state that leaching and recovery experiments were repeated twice, without reporting dispersion or independent feed-batch replication. Coated-glass characterization used SEM-EDS, WD-XRF, ICP-OES and AAS after digestion. No organism, inoculum or biological treatment was used.
Theocharis et al. (2021), Sections 2.1–2.5 and 3.1–3.2: source-described end-of-life Q-Smart panels were dismantled and thermally treated, then manually separated into clear glass, coated glass and ash; ribbons and polymer films were removed. The abstract specifies 550 degrees C for 15 minutes in excess air, while Section 2.3 describes membrane decomposition at 540–550 degrees C. Its parenthetical 1500 degrees C refers to the laboratory furnace specification, not the adopted sample treatment. Approximately 1.5-by-1.5 cm coated-glass pieces were leached. Tests compared 6 N nitric, hydrochloric and sulfuric acids at ambient temperature and a reported solid/liquid ratio of 30%, with a further hydrochloric-acid test at 80 degrees C. Nitric-acid concentrations of 1, 3 and 6 N were tested at reported solid/liquid ratios of 50% and 70%; the percentage basis is not defined. The authors state that leaching and recovery experiments were repeated twice, without reporting dispersion or independent feed-batch replication. Coated-glass characterization used SEM-EDS, WD-XRF, ICP-OES and AAS after digestion. No organism, inoculum or biological treatment was used.
Curated Evidence Points:
Support
Source:
theocharis2021
Sections 3.1–3.2, Figures 2–4 and Tables 1–2 support a characterized composite feed and dissolved metals after acid contact. Table 2 reports, for 6 N HNO3 at 25 degrees C and a stated S/L of 70%, In 47 mg/L, Ga 20 mg/L, Mo 169 mg/L, Cu 39 mg/L and Zn 105 mg/L. These are individual leachate concentrations, not extraction percentages. Section 3.2 reports faster film delamination with nitric acid (about 30 minutes) than hydrochloric acid (four days), but does not give a complete matched kinetic protocol for every Table 2 cell.
Partial
Source:
theocharis2021
The abstract and Table 1 report different coated-glass compositions: for example, In 0.02% versus 0.01% and Cu 0.05% versus 0.01%. These are not silently reconciled or used as a whole-panel denominator. The authors call extraction quantitative, but the undefined S/L basis, differing feed composition reports and absent closed inventory balance prevent an independently verified whole-module percentage. Selenium-rich solid residue is assigned from SEM-EDS in Figure 4; part of the selenium reportedly volatilizes during heating, without a demonstrated closed capture balance or unique crystalline residue-phase identification.
Context_only
Source:
theocharis2021
Section 2.6 explicitly describes preliminary solvent-extraction tests using synthetic In/Ga/Mo solutions. The 97% In and 72% Ga extraction values in Tables 3–4 therefore are not adopted as recovery yields from the actual panel leachate. Table 3 includes Ga and Mo co-extraction, and Table 4 shows Ga in the organic phase despite prose referring to raffinate. The stage starting masses are not reconciled as a closed sequential balance. Figure 1 is a Visual MINTEQ calculation, not a measured precipitation experiment. Stripping and oxide production are discussed with a citation to a separate spent-oxide-target study; this proceeding does not establish isolated CIGS-derived oxide purity or yield. Industrial deployment is not demonstrated.
Sources & References
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theocharis2021: Theocharis, M., Tsakiridis, P.E., Kousi, P., Hatzikioseyian, A., Zarkadas, I., Remoundaki, E. and Lyberatos, G. Hydrometallurgical Treatment for the Extraction and Separation of Indium and Gallium from End-of-Life CIGS Photovoltaic Panels. Materials Proceedings 5(1):51 (2021), DOI 10.3390/materproc2021005051. Complete six-page publisher PDF inspected, including all four figures and four tables; conference proceeding published 1 December 2021.
https://doi.org/10.3390/materproc2021005051 (accessed 2026-10-14)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-14T13:58:45.362685+00:00 |
codex (GPT-6; codex) | CREATE | Created a distinct end-of-life CIGS module resource with qualified abiotic leaching evidence; kept synthetic solvent extraction, inconsistent composition reports and unavailable whole-feed recovery balances explicit. |
Record source: data/records/end-of-life-cigs-photovoltaic-modules.yaml