Relationship between the Property of Cloud Point and CO<sub>2</sub> Absorption and Desorption of Amines

Abstract

Water solution of organic amine is used widely for removing acid gases, especially for CO2. Some water solution of amines have the property of thermally induced phase transition at the temperature of cloud point at which the solution becomes turbid. The energy consumption could be reduced with the assistance of phase transition during the process of desorption. Therefore, it is important to discover the relationship between absorption and desorption capacity of amines and its property of thermally induced phase transition. In this work, hexylamine with the property of phase transition at cloud point and butylamine without the property were selected to perform the comparative experiment of CO2absorption and desorption at 30-100°C. Results show that 40% water solution of hexylamine and butylamine have similar CO2absorption capacity, and the change of CO2absorption capacity of hexylamine at cloud point is not obvious. Thus it is concluded that the property of thermally induced phase transition of hexylamine would not increase its CO2absorption capacity.