Experimental study and kinetic modeling of R410a hydrate formation in presence of SDS, tween 20, and graphene oxide nanosheets with application in cold storage

Abstract Gas hydrates, or clathrate hydrates, can be used as a suitable cold/cool storage media, due to their large phase change enthalpy. In recent decades, cold production through gas hydrates as a novel and cost-effective method has motivated researchers. Refrigerants have the potential to be used in hydrate-based cold storage systems, because they can form hydrates at moderate pressures and temperatures. Hence, in this work, the kinetics of R410a (50 wt% difluoromethane + 50 wt% 1,1,1,2,2-pentafluoroethane) hydrate formation in the presence of different concentrations of SDS, tween 20, and graphene oxide (GO) was investigated. The experiments were carried out in a 300 cm3 reactor/cell at the initial pressure and temperature of 1 MPa and 279.65 K, respectively. According to the results, at all concentrations of the additives, except tween 20 at a concentration of 1000 ppm, the hydrate formation induction time decreases, compared to pure water. Furthermore, the promotion effects of SDS and GO on the quantity and rate of gas uptake, and the apparent rate constant were observed at the initial minutes of the hydrate growth process. The measured storage capacity and water to hydrate conversion show that the used additives do not change the abovementioned parameters, noticeably.