Figure 3. Growth kinetics of the CO₂ hydrates.

(a) CO₂ hydrate growth kinetics in the presence of 0.01 mol% amino acids in fresh water. The gas uptake measurements were initiated at the onset of CO₂ hydrate nucleation. (b) The correlation between the amount of gas uptake over 10 h and amino acid hydrophobicity. (c) CO₂ hydrate growth kinetics in the presence of 0.1 mol% amino acids in fresh water. (d) The correlation of gas uptake values with the amino acid hydrophobicities. The lines are the average values of the gas uptake, which were obtained every 10 s. The symbols and their error bars indicate the average and standard deviation, respectively. All the tested amino acids were found to inhibit CO₂ hydrate growth. The data for the solutions with no inhibitor or 0.1 mol% L-alanine were obtained from our previous report²⁴.