Effect of Albumin and Tryptone as environmental-friendly additives on methane hydrate formation rate: Efficacy of a protein on promotion or inhibition of hydrate growth

The objective of this study was to introduce a new edible additive to improve the kinetics of methane hydrate formation. Thus, experiments were performed on some proteins as new additives with successful applications. The effects of chicken egg white Albumin (CEWA), bovine serum Albumin (BSA), and Peptone from Casein (Tryptone) were investigated on the methane hydrate formation at an isothermal condition. The results indicated that CEWA and BSA while having a negligible foaming amount, promoted the hydrate formation rate and reduced the induction time. At best, CEWA at 0.2 wt% and BSA at 0.4 wt% increased the rate of hydrate formation by 116%, and 112%, respectively. Tryptone's effect was completely different and acted as an inhibitor for the methane hydrate formation and increased the reaction time by 142% at the concentration of 0.4 wt%. The results lead us to understand that the structure and properties of a protein can directly affect its function and make it an inhibitor or a promoter for gas hydrate. The experiments indicated that Albumins and Tryptone are promising as eco-friendly and nontoxic substances and could be used for further investigations.