Organic salts as kinetic and thermodynamic inhibitors for CO2 hydrate precipitation

Abstract

In this work, we opted for the use of CO2 gas for the respective experiments, due to its greater solubility in water when compared to hydrocarbons, as well as possible applications in pre-salt oil fields (such as the Libra field), where the amount of CO2 varies between 40 and 80%, obstructing the pipelines in the CO2 capture stage. In this context, the objective of this work is to obtain organic salts of different amino acids and alcohols (biodegradable and environmentally friendly compounds) and to test them in a pilot gas hydrate synthesis plant, with the goal of evaluate the inhibition potential of these compounds for CO2 hydrates. The organic compounds were synthesized with good yields and were characterized by NMR (13C and 1H) and elementary analysis. The compounds with greater hydrophilic character showed thermodynamic inhibition effects for the tested condition, while the hydrophobic compounds showed kinetic inhibition effects. The fundamental knowledge and the mechanism on the kinetic and/or thermodynamic inhibition of CO2 hydrates from organic salts obtained in this study are beneficial and extremely important, given the good results presented and the unprecedented application of the tested compounds.