Light-driven ultrafast dual C–C cleavage and coupling of dihydroxyacetone into high-purity carbon monoxide and ethylene glycol†

Abstract

Bulk chemicals, such as carbon monoxide (CO) and ethylene glycol (EG), derived from biomass feedstocks instead of traditional fossil fuels present a renewable and sustainable energy alternative. However, their direct production under ambient conditions with high purity is challenging. Herein, we report a distinctive photochemical process to produce CO together with EG through the ultrafast C–C cleavage of dihydroxyacetone induced by ultraviolet illumination at ambient temperature and pressure in water. The obtained CO yield was nearly 98% with a high purity above 99.9%, and the EG yield was nearly 80%. The two hydroxyls at the alpha carbons of dihydroxyacetone reduced the energy barriers of photoexcitation and the radical reaction, accounting for fast C–C cleavage to produce CO and EG. A home-built flow reactor achieved the continuous production of CO and EG over 1000 h and maintained efficient operation for 100 h in the sunlight-electricity-ultraviolet light mode. Benefitting from the fast reaction rate and high-purity gas generation, a safe, laboratory-scale, portable, ready-to-use CO generator was designed and assembled. The maximum CO production rate of the CO generator reached 30 mL min⁻¹, and CO purity reached over 99% for 25 L.