Geopolymer-zeolite composite materials for carbon capture applications: adsorption tests and modelling of thermal effects

As the need for achieving carbon neutrality in industrial processes and energy production increases following rising worries of the scientific community towards the effects of climate change, researchers attention has been focused on finding competitive ways to obtain carbon dioxide sequestration from gaseous currents such as flue gas. Carbon capture is considered an essential strategy to contain the increase of global average temperature below the threshold of 1.5°C estimated by the Intergovernmental Panel on Climate Change to cause irreversible climate changes and environmental damage [1, 2]. Nowadays, the most common sequestration technology is the ammine absorption, but as this process presents limitations due to high costs, toxicity and volatility of amines other methodologies are being evaluated. In particular, adsorption processes offer a very promising solution, both clean and reliable, and are therefore becoming of increasing interest thanks also to their potential for retrofit application to existing industrial plants [3]. with research focused both on sorbent material development and process optimization. Different materials have been proposed for CO2 sorption, from conventional sorbents such as active carbon to Metal-Organic Frameworks, zeolites and supported amines [4]. A good adsorbent material should possess an high adsorption capacity for CO2 and large selectivity towards other gases, while also being thermally stable and possessing good mechanical resistance in handling and loading operations [5].