Thermodynamics and kinetics of CO2 hydrate formation in the presence of cellulose nanocrystals with statistical treatment of data

Abstract

Carbon dioxide hydrate was formed in aqueous suspensions of cellulose nanocrystals (CNC) and the induction time and rate of hydrate crystal growth was compared to data obtained when CO2 hydrate was formed in pure water (blank). CNC concentrations of 0.13, 0.5 and 0.75 wt% were employed to determine whether CNC could reduce the induction time and enhance hydrate growth rate as it has been reported for carbon nanotubes and other nanoparticle suspensions. Hydrate formation experiments were carried out in two different crystallizers. The first set-up was in semi-batch operation mode while the second set-up was in batch operation mode. The results show that the CNC did not have a statistically significant impact on CO2 hydrate formation. This study also raises questions about the validity of conclusions and claims made in the literature about the effect of carbon nanotubes and other nanoparticles on gas hydrate formation. Those claims were based on very small sample sizes and without statistical data analysis.