A Dual-Role Additive as a CO2 Hydrate Promoter and a Corrosion Inhibitor: Application in CO2 Capture, Transportation, and Sequestration

Abstract

Chemical additives are known to play a crucial role in the deployment of gas hydrate-based CO₂ capture, transportation, and sequestration (CCTS) technologies. In this study, we investigate the effectiveness of a new additive, 1,2,3-benzotriazole (BTA), in promoting CO₂ hydrate formation and inhibiting corrosion. We evaluated the kinetics of CO₂ hydrate formation using various concentrations of BTA, ranging from 0.1 to 1.0 wt %, under operating conditions of 3.2 ± 0.2 MPa pressure and approximately 274 ± 0.5 K temperature. Moreover, we examine the impact of the gas-to-liquid ratio on the CO₂ hydrate formation kinetics. The results indicate that BTA significantly enhances the hydrate formation kinetics and improves CO₂ storage capacity. Additionally, we conducted electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), and gravimetric analysis to assess the corrosion inhibition efficacy of BTA in 1 M HCl and CO₂-saturated saline water (3.5% NaCl) at various concentrations. Our findings demonstrate that BTA serves a dual function as a hydrate promoter and a corrosion inhibitor.