Seyed Abdollatif Hashemifard

The absorption of acid gases using alkanolamines is considered a key method in the oil and gas industry. However, the presence of heat stable salts (HSS), formed by the reaction of amines with strong acidic compounds, leads to several operational challenges, including reduced acid gas absorption capacity, increased solution viscosity, foaming, corrosion, and ultimately, decreased process efficiency. This study investigates the formation mechanisms, chemical structures, and removal methods of HSS from amine solutions. Based on the evaluation and comparative analysis of various solutions, ion-exchange-based methods were identified as the most effective purification strategies due to their high efficiency and ability to preserve amine quality. In contrast, methods such as chemical neutralization and adsorption exhibited limited effectiveness, with removal efficiencies below 50%. Other techniques such as electrodialysis, electrosorption, and nanofiltration, despite achieving high removal efficiencies (70–90%) and requiring no chemical additives, are mainly justifiable as complementary or selective approaches due to operational costs and challenges such as membrane fouling. This research provides a comprehensive guide for optimizing acid gas absorption processes in refineries and petrochemical industries, and establishes a foundation for future studies on the development of advanced technologies for amine solution purification.