posted on 2021-04-01, 22:51authored byJiafei Zhao, Yanzhen Liu, Lei Yang, Lunxiang Zhang, Yongchen Song
A deeper understanding of the kinetics
of CO2 hydrate
formation in the complicated natural environment is required for its
enhanced sequestration. Here we found that the organics-coated nanoclays
enriched in the natural sediments could contribute to a 92% decline
of the induction time of hydrate formation. This can be ascribed to
the negative charges carried by the organics and the resulting ordered
arrangement of the surrounding water molecules. It was, for the first
time, proposed that the abundant functional groups from the coating
organics could function as a protecting crust enabling the system
more resistant to the acidification potentially upon the CO2 sequestration; besides, the negative charges could help prevent
the deposition of the nanoclays via interparticle repulsive forces.
These would consequently secure their sustainable promoting effect
on hydrate formation. The findings suggest the deposits of gas hydrate
a kinetically promising geological setting for the CO2 sequestration
via forming hydrates.