Huang, Yu-FongYu-FongHuangPEI-TE CHIUEHLo, Shang-LienShang-LienLo2025-12-182025-12-182026-02-2613835866https://www.scopus.com/record/display.uri?eid=2-s2.0-105020901906&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/734758Metal recovery from spent copper indium gallium selenide (CIGS) solar cells (SCs) was conducted using microwave pyrolysis, thermal oxidation and thermal chlorination methods in sequence. Microwave pyrolysis can delaminate spent CIGS SCs and provide energy recovery. Total recovery of selenium can be achieved by using thermal oxidation. To save time and energy, a four-stage thermal chlorination process for total recovery of gallium, indium and copper from spent CIGS SCs was proposed. Reaction kinetics was analyzed to determine the processing time required for the recovery of metals from spent CIGS SCs at specific heating temperatures. The gallium to indium ratio of the thermal chlorination product generated at 400 °C for 2 h is close to the ratio of the spent CIGS SCs used in this study and the optimal ratios exhibiting the highest energy conversion efficiency. The total revenue of metals and energy recovery from 1 kg spent CIGS SCs would be up to USD 8.34, which shows that the recycling of spent CIGS SCs can bring in great economic benefits and incentives. The recycling of spent CIGS SCs can make the industry become a system of circular economy by using the methods with the operational parameters proposed in this study.falseCIGS solar cellsMetal recoveryMicrowave pyrolysisReaction kineticsThermal chlorinationThermal oxidationjournal article10.1016/j.seppur.2025.1359752-s2.0-105020901906