Non-equilibrium wet-dry cycling acts as a catalyst for chemical reactions

Abstract

Recent experimental studies suggest that wet-dry cycles and coexisting phases can each strongly alter chemical processes. The mechanisms of why and to which degree chemical processes are altered when subject to evaporation and condensation are unclear. To close this gap, we developed a theoretical framework for non-dilute chemical reactions subject to non-equilibrium conditions of evaporation and condensation. We find that such conditions can change the half-time of the product's yield by more than an order of magnitude, depending on the substrate-solvent interaction. We show that the cycle frequency strongly affects the chemical turnover when maintaining the system out of equilibrium by wet-dry cycles. There exists a resonance behavior in the cycle frequency where the turnover is maximal. This resonance behavior enables wet-dry cycles to select specific chemical reactions suggesting a potential mechanism for chemical evolution in prebiotic soups at early Earth.