화학공학소재연구정보센터
Chemical Engineering Science, Vol.132, 202-215, 2015
Influence of cationic and non-ionic surfactants on the kinetics of mixed hydrogen/tetrahydrofuran hydrates
In this study, the kinetics of mixed hydrogen/tetrahydrofuran (THF) hydrate formation in presence of cationic dodecyl trimethylammonium chloride (DTAC) surfactant and non-ionic Tween-20 (Polysorbate 20) surfactant was evaluated. Stoichiomenic concentration of 5.6 mol% THF solution with varying surfactant concentrations from 0.01 wt% to 1 wt% were experimented and their effect on the mixed hydrogen/THF hydrate formation was studied. Marginal improvement in the mixed hydrogen/THF hydrate formation rates were observed for both the chosen surfactants with maximum of about 20% increase using 0.5 wt% DTAC and 0.1 wt% Tween-20. Decomposition kinetics of mixed hydrogen/THF hydrates using thermal stimulation (Delta T=20 K) with and without stirring showed that stirring improved the decomposition kinetics with t(90) of 22.2(+/- 0.8) min in comparison to t(90) of 29.1(+/- 0.6) min for the experiments conducted without stirring. The presence of surfactant did not significantly affect the decomposition kinetics for experiments conducted both with and without stirring. Methane/THF mixed hydrate formation under similar experimental conditions studied show that the presence of 0.5 wt% DTAC surfactant resulted in reduction of hydrate formation rates by approximately 20%. The effect of surfactant in presence of THF characteristically differs depending upon the guest gas and the system under investigation. (C) 2015 Elsevier Ltd. All rights reserved.