Kinetic Studies of Gas Hydrates for CO₂ Capture in the Presence of Nanoparticles

Abstract

High levels of CO2 in the atmosphere have led to drastic climate changes, and along with the threat of the impact of a two or more-degree temperature rise, intensive research on carbon capture has opened new and promising avenues. The hydrate-based CO2 capture method is an environmentally friendly approach, and the application of additives such as nanoparticles has shown a promising avenue for increasing the rate of hydrate formation. This research delved into the impact of both nano- and microparticles on the kinetics of CO2 hydrate formation. The selected chemical substances included nanoparticles and nanoplatelets of aluminum oxide, copper oxide, and graphene, respectively, as microparticles of graphite powder, zinc oxide, and magnesium nitrate hexahydrate. Additionally, the study examined the influence of temperature and pressure through experimental means and the kinetics affecting the gas hydrate formation such as induction time, storage capacity, gas consumption, water conversion percentage, and the ratio of gas consumed to moles of water. For this investigation, nanofluids with concentrations of additives ranging from 0.1 to 1.2 wt % including 0.05 wt % sodium dodecyl sulfate, were employed. In all experiments involving additives, the initial conditions for temperature and pressure were set at 275.8 K and 3.41 MPa, respectively. The study’s results demonstrate that nanoparticles enhance the kinetics of CO2 hydrate formation, leading to higher storage capacity, increased water conversion, and a faster rate of gas absorption. Additionally, in hydrate formation, the use of nanoparticles reduced the induction time. These findings are promising for the potential application of nanoparticles in the storage of CO2 gas within gas hydrates.