Can surfactant promote cyclopentene hydrate formation for cool storage?

Abstract

Some surfactants have been observed to enhance hydrate formation kinetics, but other surfactants have no influence on improving hydrate formation. We used some anionic surfactants (MES, AOT, sodium oleate, potassium oleate) and nonionic surfactants(Tween series and AEO series))with different HLB value to study the influence mechanism of hydrate formation in this study. The influence of surfactants on nucleation time, cool storage in hydrates and cycling stability of cyclopentene hydrate formation under quiescent conditions are studied. Anionic surfactants cannot promote cyclopentene hydrate formation in this work. While Tween80 and AEO-9 with HLB in the range of 14 ∼ 15 can effectively promote cyclopentene hydrate formation. But when the HLB values of Tween series or AEO series increase or decrease, they cannot promote cyclopentene hydrate formation. The hydrate nucleation time is the shortest and the cool storage of cyclopentene hydrates is the largest when the concentrations of Tween80 and AEO-9 are 1.0 wt% and 2.5 wt%, respectively. Adding proper amount of Tween80 or AEO-9 also can decrease the dispersion of hydrate nucleation and improve the hydrate formation/dissociation cycle stability.