Xerogel-immobilized amines as a new medium for CO2 separation from gas mixtures

IEC 6

M. Aresta, Angela Dibenedetto, and Robert Girardi. Department of Chemistry and METEA Research Center, University of Bari, Via Celso Ulpiani, 27, Bari, 70126, Italy
The absorption of carbon dioxide by liquid amines is one of the technologies that have been developed for its separation from flue gases. Mono-amines such as monoethanolamine find a large use. The major drawback is the loss of amine, due to their volatility. Therefore, using solid amine may help to reduce the loss. In this work we describe the use of di-amines as efficient media for the separation of carbon dioxide from a gas mixture. Differently from mono-amines they are able to pick-up one mol of CO2 per mol of amine affording an intra-molecular ammonium carbamate. Moreover, we discuss the use of xerogel-immobilized amines which are able to absorb and desorb carbon dioxide with high efficiency at higher temperature than liquid amines.