Old solar panels help turn power plant CO2 into valuable chemicals

Japanese researchers from Yokohama National University, Electric Power Development Co., Ltd., and Japan’s National Institute of Advanced Industrial Science and Technology (AIST) have developed a novel method to convert carbon dioxide (CO2) from thermal power plant exhaust directly into valuable organic chemicals using recycled silicon wafers from discarded solar panels. By pretreating crushed solar panel silicon wafers with hydrochloric acid to remove aluminum contaminants, the team enhanced the wafers’ ability to act as reducing agents in the reaction. The process involves combining the untreated exhaust gas (containing about 14% CO2) with water, a catalyst (tetrabutylammonium fluoride), and the recycled silicon powder, resulting in the efficient production of formic acid and formamide without the need for CO2 purification. This breakthrough offers a dual environmental benefit: it repurposes waste silicon from obsolete solar panels—addressing the growing issue of photovoltaic panel disposal predicted to reach tens of millions of metric tons by 2050