The formation of structure I hydrate in presence of n-octyl-β-D-glucopyranoside

•OGP was first time used in hydrate formation and significantly increased RWH and rR.•The performance of OGP on increasing RWH was better than those of other surfactants.•OGP had little negative thermodynamic effect on hydrate formation.•The increase in RWH affected the effects of wp,0 and pressure on hydrate formation.•The model in this work can accurately predict the Peq of C2H4OGP solution systems. A new promoter for hydrate-based technologies (HBTs) called n-octyl-β-D-glucopyranoside (OGP) was proposed in this work. The effect of OGP on the properties of liquid phase, the thermodynamic effect of OGP on structure I hydrate (formed by ethylene and water) and the effect of OGP on the formation process of structure I hydrate were investigated. To determine the controlling factors of the hydrate formations, a new model which can accurately predict the thermodynamic equilibrium hydrate formation pressures of corresponding systems was proposed, and the average relative deviation of the model is 1.6%. The experimental results show that, OGP was a low foaming promoter with high surface activity, and OGP rarely affected the thermodynamic phase equilibria of corresponding systems. OGP not only significantly increased the hydrate formation rate (rR) but also increased the conversion rate of the water into hydrate (RWH) from about 61.2% to about 95.5%, and the maximum RWH of the ethylene gas-OGP solution system in this work was 97.5 ± 1.6%. The optimum initial OGP concentration for HBTs was 0.2 mass%. The difference in rR caused by the difference in pressure significantly decreased as RWH increased from 10% to 40%. rR did not significantly decrease during the period that RWH increased from 40% to 65%, and the steady rR during that period benefits the application of HBTs.