ABSTRACT: We propose a processing alternative for replacing the traditional and environmentally dangerous solvents (as monoethanolamine, diethanolamine) in the process of CO2 capture. We use a computer aided molecular design (CAMD) methodology for exploring the use of ionic liquids (ILs) as solvents for CO2 capture. The CAMD formulation is solved as a mixed-integer nonlinear programming (MINLP) problem, the objective is to obtain an optimal molecular structure of an ionic liquid for CO2 capture from a post-combustion (PC) gas stream (GS). We use a set of functional groups and anions, whose combination forms different kinds of ILs that have the potential to solubilize CO2 and remove it from PC-GS. The properties of ILs are estimated by group contributions methods and the equilibrium behaviour by empirical correlations. To achieve the separation task the problem was divided in two cases. In the first case, we assume that only CO2 is present in GS. In the second case, we consider a typical PC-GS. In both cases, the separation takes place in a single equilibrium stage. After obtaining the IL, and assessing the potential for high recovery of CO2, we checked that the IL could realize such a separation task by using an absorption column. The results indicate that the designed IL is capable of performing the carbon capture, removing more than 95% of CO2 from PC-GS. Moreover, a tentative steady-state process design of the whole CO2 recovery process is also reported. We also discuss closed-loop control of an industrial scale system for CO2 capture based on the use of Ionic Liquids.
Bio-sketch: Antonio Flores-Tlacuahuac is currently a Professor in the Department of Engineering and Chemical Sciences at the Universidad Iberoamericana in Mexico City. He received a B.Sc. degree from Universidad Autonoma de Puebla (1985) and a Ph.D. degree from Imperial College of Science, Technology and Medicine (1994), both in chemical engineering. He worked for Instituto Mexicano del Petroleo (1985) and Sidetec Electronica (1987-1989). He has served as consultant for several polymer and pharmaceutical companies. His research interests are in the areas of mathematical modeling, simulation, optimization, and control of processing systems with emphasis in new alternative energies and polymerization systems. He is a member of the Society for Industrial and Applied Mathematics (SIAM) and the American Institute of Chemical Engineers.