Upcycling Greenhouse Refrigerants into Sustainable Chemical Feedstocks

Abstract Rising global temperatures are driving demand for air conditioning, while leakage of high-GWP refrigerants further accelerates warming. In addition, the transition to low-GWP alternatives generates large volumes of waste refrigerants, which are currently treated by energy-intensive thermal destruction processes that often lead to the loss or downgrading of fluorine resources. Although dehydrofluorination offers a promising route to convert hydrofluorocarbon (HFC) refrigerants into low-GWP alternatives, conventional approaches are often limited by catalyst deactivation and degradation of target products caused by hydrogen fluoride (HF) as a by-product. Here, we show a practical continuous-flow process that overcomes these barriers by using alkali metal fluoride catalysts and silica as a sacrificial reagent to capture HF irreversibly as gaseous silicon tetrafluoride. This system enables the direct upcycling of legacy refrigerants into sustainable chemical feedstocks, including low-GWP hydrofluoroolefins (HFOs) and key monomers for fluoropolymers. Furthermore, selective conversion of the HFC-125 component within the near-azeotropic refrigerant blend R410A alters the boiling-point distribution, providing a potential route to HFC-32 recovery. Waste glass from end-of-life solar panels can also serve as the silica source under the reaction conditions.