Nowadays, several research and development efforts are devoted to find processes that can mitigate global warming. This phenomenon is caused by anthropogenic emissions of greenhouse gases, such as carbon dioxide and methane. In this way, adsorption processes are a promising alternative for capturing and separating greenhouse gases because it presents a lower energy cost, compared to other methods, and especially for the possibility of regenerating the adsorbent material without generating by-products. In addition, adsorption processes can be used for upgrading natural gas, a fuel with a low emission of carbon dioxide per kilowatt of energy produced. Thus, the main objective of this work was the development of an adsorption simulator to study the separation of CO2/CH4/N2 mixtures in a fixed bed including the conceptual design of a cyclic pressure swing adsorption (PSA) process for CO2 capture and purification. In order to achieve this objective, a mathematical model has been developed to describe the adsorption of mixtures in a fixed bed solved through numerical methods available in the literature. The numerical implementation was performed in MATLAB® simulation environment. The implemented model was tested and validated by simulating numerical examples of fixed bed adsorption available in the literature. Also, the model was used to fit experimental data collected at LSRE/CIMO-IPB concerning the CO2 adsorption in a fixed bed containing Activated Carbon derived from a municipal solid waste compost (AC-MSW). It was found, that the non-isothermal fixed bed adsorption model developed accurately described the experimental data. Finally, the thermodynamic and kinetic data collected from the best AC-MSW studied material was used to design a conceptual PSA unit using the numerical model and simulator developed. The conceptual PSA process was designed to capture carbon dioxide in a real post-combustion stream with data supplied by Persian Gulf Star Oil Company (PGSOC). Process performance parameters of the conceptual PSA simulated, indicate that is possible to achieve between 9.5-25% purity and high recovery of CO2 (above 87%) with the AC-MSW material, depending on the purge to feed ratio.
