ORS9-1056
Catalytic recycling of silicones into chlorosilanes
Topic
S9. Polymer Technology for Sustainability
When and Where
Sep 30, 2026
11:50 - 12:05
Room 201
Session Chairs
Heejoong KIM
Presenter(s)
Lucie Riviere (Universite Claude Bernard Lyon 1, CNRS, CPE Lyon, UMR 5128, Laboratory of Catalysis, Polymerization, Processes and Materials (CP2M), 43 Bd du 11 Nov. 1918, Villeurbanne, France)
Co-Author(s)
Abstract
Chemical recycling of silicones into monomers is a key strategy for developing a sustainable circular polymer economy. However, the recycling of silicone materials, especially highly cross-linked elastomers and resins, remains challenging due to the robustness of the silicon-oxygen backbone and the limited efficiency of existing methods.
In this context, silicone depolymerization into chlorosilane precursors offers an original catalytic route, as chlorosilanes are essential building blocks for both silicone production and microelectronics applications (e.g., silicon wafers and semiconductor devices). Chlorosilanes are particularly attractive targets since they can be distilled and thus purified, enabling potentially infinite reuse of silicon atoms without downcycling.
We present a general and efficient method for the depolymerization of a wide range of silicone-based materials, including post-consumer silicone waste, formulated elastomers and highly cross-linked resins. The reaction proceeds at mild temperatures (40-110 °C) using gallium- or iron-based catalysts, and shows good tolerance toward additives and complex formulations typically found in industrial silicone waste. Near-quantitative yields of (methyl)chlorosilanes are obtained, highlighting the efficiency and selectivity of the process.
This method enables overcoming the thermodynamic barrier associated with the exchange of silicon-oxygen bonds for silicon-chlorine bonds and represents a promising approach toward closed-loop recycling of silicones compatible with existing industrial infrastructures.
In this context, silicone depolymerization into chlorosilane precursors offers an original catalytic route, as chlorosilanes are essential building blocks for both silicone production and microelectronics applications (e.g., silicon wafers and semiconductor devices). Chlorosilanes are particularly attractive targets since they can be distilled and thus purified, enabling potentially infinite reuse of silicon atoms without downcycling.
We present a general and efficient method for the depolymerization of a wide range of silicone-based materials, including post-consumer silicone waste, formulated elastomers and highly cross-linked resins. The reaction proceeds at mild temperatures (40-110 °C) using gallium- or iron-based catalysts, and shows good tolerance toward additives and complex formulations typically found in industrial silicone waste. Near-quantitative yields of (methyl)chlorosilanes are obtained, highlighting the efficiency and selectivity of the process.
This method enables overcoming the thermodynamic barrier associated with the exchange of silicon-oxygen bonds for silicon-chlorine bonds and represents a promising approach toward closed-loop recycling of silicones compatible with existing industrial infrastructures.
