Enhancing circular economy of waste refrigerants management using deep eutectic solvents

Abstract

The use of fluorinated gases (F-Gases) in the refrigeration industry is subjected to increasingly restricted laws, such as the F-Gas regulation 517/2014 in Europe, due to their high global warming potential (GWP). Currently, there is a lack of standardized recovery technologies, so most of the F-gases used to be incinerated at the end of their life cycle. This is contrary to the principles of circular economy and development of sustainable processes, which should consider the recycling of these gases. The difficult separation of F-Gases blends might have a solution on the use of Deep Eutectic Solvents (DES) as green absorbents. In this work, the performance of a DES was assessed for the recovery of pentafluoroethane (R-125) and difluoromethane (R-32) from the commercial refrigerant R-410A combining a dual approach based on the experimental measurement of the F-Gases absorption in the DES and on process simulation using Aspen Plus. The environmental impacts of the designed recovery process (circular economy scenario) were examined using a life cycle assessment (LCA) approach and it was compared to the environmental impacts of the industrial manufacture of R-125 (lineal economy scenario). In comparison to the conventional R-125 production, the results of the proposed recovery process revealed a significant reduction in the environmental impacts between 92 and 99% with a recovery of R-125 of 76.7%, acceptable for its further reuse (purity of 98% w/w). The results of this work could pave the way for developing innovative F-Gases recovery technologies using DES, which can contribute to reduce the environmental impacts of these compounds via circular economy strategies.