Sucralose, an eco-friendly novel promoter of carbon dioxide hydrate formation: Kinetic investigation

Abstract

Gas hydrates represent a cutting-edge technology for the separation and storage of greenhouse gases, capturing the interest of numerous researchers. Nevertheless, the challenges of low storage capacity and slow hydrate formation can be surmounted through the application of kinetic promoters. This study investigates the kinetic parameters of CO2 hydrate formation with the influence of sucralose, an eco-friendly additive, at various concentrations. Lab-scale experiments were conducted in a reactor, with initial conditions of 3 MPa pressure and 274.15 K temperature. Among the tested concentrations, the addition of 0.75 wt% sucralose exhibited the highest gas consumption and storage capacity. Compared to pure water at t = 300 min, the inclusion of 0.75 wt% sucralose resulted in a 37 % increase in gas consumption and a corresponding enhancement in storage capacity. Likewise, at t = 20 min, the water-to-hydrate conversion and storage capacity (SC) increased by approximately 35 % compared to pure water. However, as the sucralose concentration in the aqueous solution surpassed 0.75 wt%, the promoting effect on gas consumption declined, showing a diminishing return. Notably, a slight inhibitory behavior was observed during the experiment with a 10 wt% sucralose concentration. Furthermore, the experiments were replicated for certain sucralose concentrations in the aqueous solution under the same initial pressure but at an elevated temperature of 276.15 K. The results demonstrated a reduction in the promoting effect of sucralose, suggesting that raising the cell temperature during the hydrate formation process negatively impacted the kinetic parameters.