UKCCSRC Call 2 Project: Process-performance indexed design of task-specific ionic liquids for post-combustion CO2 capture

Increased population and increased economic activity have one important thing in common: increased energy demand. More and more, concern is mounting surrounding the broader environmental impact associated with this, and we are forced to consider the harsh reality that societies which systematically abuse and exploit their ecosystems tend not to survive. Historically, once a population had exhausted their local ecosystem, those who could, would relocate to another area, whilst those who could not tended to die out. In our globally connected world, we do not have the option of relocation; therefore it is imperative that we find a way to redress the adverse environmental impact that has historically been associated with anthropogenic economic activity. This work proposes to address one important aspect of this challenge; how to decarbonise power generation in a costeffective and environmentally benign manner. First patented in 1932, amine-based technologies for removing CO2 from the exhaust gases of large industrial processes are a well accepted and mature option. However, their deployment on a scale commensurate with the power generation industry would entail their utilisation on a scale of an entirely different order of magnitude. This step change brings with it two important challenges; the large cost resulting from the capital and ongoing operational cost associated with the deployment of CCS and also the possibility of ancillary environmental concerns resulting from the release of amines and their associated degradation products into the wider environment. This research proposes to solve this problem by using a new class of material, ionic liquids, for solvent based CO2 capture to produce carbon negative electricity - in effect taking CO2 out of the atmosphere and ultimately reversing global warming. Ionic liquids are an exciting new class of materials which, rather than being composed of molecules, are composed of individual anions and cations which interact to define their thermophysical properties. They are almost infinitely tunable as one can in effect design a task specific ionic liquid for a particular property, e.g., to absorb CO2. However, there is an important challenge associated with this; the sheer size of the potential design space. At the time of writing, there are approximately 109 potential combinations on anion and cation - far too many for design by experiment or heuristic. Thus, this research proposes to tackle this problem by performing this material design in a computational environment using a process performance index. In other words, the development and incorporation of a new theory for designing task specific ionic liquids in dynamic non-equilibrium models of a CO2 capture process and proposing new ionic liquids based on how they affect the efficiency of the power plant to which these processes are attached. The success criteria of this project are the development of a new, environmentally benign ionic liquids based CO2 capture process which reduces the cost of capture by approximately 40% in comparison with the current benchmark technology. Vital to the success of this work is the cutting edge collaboration between experimental and theoretical research groups in the Department of Chemical Engineering and the Centre for Environmental Policy at Imperial College London in addition to leading research groups in the Join BioEnergy Institute in San Francisco, USA. Important outputs of this work will be new technologies for the design of task specific ionic liquids in addition to designs operational strategies for ionic liquids based CO2 capture from large fixed point emission sources. Grant number: UKCCSRC-C2-199.

Tags: Carbon capture and storage, NERC_DDC
Organization: British Geological Survey (BGS)