This work package is dedicated to identifying and producing CO2 capture materials that can compete with the current - though not satisfactory - benchmark in the field. The potential for scale-up of these materials is to be explored using unique facilities available at UK universities.
Imperial College will synthesise and characterise a number of water stable MOFs. Rapid screening will be conducted using a thermogravimetric and/or a sorption stable MOFs analyser. We will test first MOFs with reported promising capacities. The best performing materials will be tested at pressures up to 30 bar using an IGA TGA system to simulate potential industrial and natural gas processing. Additionally, dynamic adsorption tests will be performed using a breakthrough set-up and a simulated flue gas stream and regeneration of the materials will be evaluated. This approach will address the current knowledge gap in terms of MOFs’ potential at scale with respect to: (1) their stability in the presence of SOx and NOx and (2) their dynamic performance. Highly promising materials will be put forward as potential projects for large-scale testing in the SALT reactor (see WP A2) using flexible research funding. In addition, adsorbents based on activated carbon will be investigated. In particular, Imperial College will focus on activated carbons derived from biomass waste, which can be made cheaply. Using post-synthetic procedures, we will incorporate sulphur-containing functional groups as a way to enhance CO2 capture. This approach complements the University of Nottingham’s work on N-containing activated carbons. Similar testing protocols as those described for MOFs will be employed. Work Package A1b Inorganic porous materials for chemical looping combustion (CLC) Inorganic porous chemical looping materials will be developed for both H2/O2 production and standard “unmixed” combustion. Preliminary Imperial College studies have produced highly porous Fe2O3 and CuO carriers retaining strength and reactivity over multiple cycles. Besides O2 carriers containing only one active metal (and the support material), mixed-metal oxides (MMO) will be produced. Those contain, e.g. oxides of Cu, Mn, Al and/or combined phases. Kinetics and thermodynamics (e.g. position and slope of the phase equilibrium curve between the two relevant oxidation states) will be optimised. The work will be used in pilot demonstrations at Cranfield University, where the low-cost CLC materials can be tested. Porosity, microstructures, and mechanical properties of the materials in both of the above, and their relationships, will be characterised by the combination of various analytical techniques (e.g. XRD, SEM, BET, TEM). A TGA with integrated calorimetric measurement will measure heats of adsorption and heat capacities. After initial screening work, a high-pressure fluidised bed reactor will be used under realistic conditions relevant to industrial deployment of the technology.