Enhancements in mass transfer for carbon capture solvents part I: Homogeneous catalyst. (August 2017)

• Record Type: Journal Article
• Authors: Widger, Leland R.; Sarma, Moushumi; Bryant, Jonathan J.; Mannel, David S.; Thompson, Jesse G.; Lippert, Cameron A.; Liu, Kunlei
• Is Part Of: International journal of greenhouse gas control. Volume 63(2017)
• Page Start: 249
• Page End: 259
• Publication Date: 2017-08
• Subjects: Post-combustion -- CO2 capture -- Mass transfer -- Amine -- Catalyst -- Additives; Greenhouse gases -- Environmental aspects -- Periodicals; Air -- Purification -- Technological innovations -- Periodicals; Gaz à effet de serre -- Périodiques; Gaz à effet de serre -- Réduction -- Périodiques; Air -- Purification -- Technological innovations; Greenhouse gases -- Environmental aspects; Periodicals; 363.73874605
• DOI: 10.1016/j.ijggc.2017.05.019
• Languages: English
• ISSNs: 1750-5836

Abstract

Highlights: The addition of a small molecule Carbonic Anhydrase mimic (1 ), as a homogenous CO2 hydration catalyst, increases mass transfer into amine-based CCS solvents. The kinetically slow, thermally stable, and low enthalpy A2P/AMP solvent blend is a good candidate for catalytic enhancement by homogenous CO2 hydration catalysts. The CO2 hydration catalyst (1 ) is stable to the harsh thermal and oxidative conditions in an industrial CCS process, with a projected lifetime >1500 h. The cost of1 is estimated to be ∼$0.25 per liter of carbon capture solvent, which roughly equates to $100–$200 per megawatt of electricity generated. Abstract: The novel small molecule carbonic anhydrase (CA) mimic [Co III (Salphen-COO − )Cl]HNEt3 (1 ), was synthesized as an additive for increasing CO2 absorption rates in amine-based post-combustion carbon capture processes (CCS), and its efficacy was verified.1 was designed for use in a kinetically slow but thermally stable blended solvent, containing the primary amines 1-amino-2-propanol (A2P) and 2-amino-2-methyl-1-propanol (AMP). Together, the A2P/AMP solvent and1 reduce the overall energy penalty associated with CO2 capture from coal-derived flue gas, relative to the baseline solvent MEA.1 is also effective at increasing absorption kinetics of kinetically fast solvents, such as MEA, which can reduce capital costs by requiring a smaller absorber tower. The transition from catalyst testing under idealized laboratory conditions, to process relevant lab- and bench-scale testing adds many additional variables that are not well understood and rarely discussed. The stepwise testing of both1 and the novel A2P/AMP solvent blend is described through a transition process that identifies many of these process and evaluation challenges not often addressed when designing a chemical or catalytic additive for industrial CCS systems, where consideration of solvent chemistry is typically the primary goal.