Abstract:Molybdenum in waste copper indium gallium selenide (CIGS) thin film solar cell chips has high recovery value. A process of "oxidizing acid leaching - removal of selenium with sodium sulfite - extraction" was proposed to recover molybdenum in stainless-steel substrate CIGS solar cell chip. The results show that "hydrogen peroxide + sulfuric acid" can leach metal elements in coating without harming the stainless-steel substrate. Influence of solid-to-liquid ratio and amount of sulfuric acid on leaching was investigated. Under the optimal process conditions, leaching rate of majority metal elements in waste chips is more than 95%. "N235+isooctanol+kerosene" can extract molybdenum efficiently in acid leaching solution, but selenium will be co-extracted with molybdenum. After selenium precipitation using "sodium sulfite + hydrogen peroxide", molybdenum extraction rate can reach 98% above, while other metals are hardly extracted. This study provides an effective method for treatment of waste chips of copper indium gallium selenium thin-film solar cells on stainless steel substrates.