Strong dependency on fossil fuels and the associated price and supply chain risk increase the need for more efficient utilisation of existing non-renewable energy sources. Carbon capture and hydrogen purification technologies are expected to play a key role in the future low-carbonised energy matrix. Integrated Gasification Combined Cycles (IGCCs) are one of the emerging clean coal technologies which pave the way for producing power from coal with a higher net power efficiency than conventional PC-fired boiler power plants. It is also advantageous that in an IGCC power plant a carbon capture unit can be applied to a stream having a very high CO2 partial pressure ahead of gas combustion that would not be available in case of a PC-fired boiler power plant, leading to less energy penalty involved in carbon capture. At the same time, the production of ultrapure hydrogen is both a sought target and an appropriate environmental solution because it is commonly utilised as feedstock in refineries’ hydrotreaters and hydrocrackers as well as energy carrier in fuel cells. A high purity of hydrogen has been commercially produced out of raw synthesis gas using a Hydrogen Pressure Swing Adsorption (H2 PSA) process. In this thesis, it was aimed to design and optimise a bespoke H2 PSA system tailored for a decarbonised syngas feed originating from a carbon capture unit. Therefore, a novel H2 PSA has been studied that is applied to an advanced IGCC plant for cogenerating power and ultrapure hydrogen (99.99+ mol%) with pre-combustion CO2 capture. In designing the H2 PSA, it is essential to increase the recovery of ultrapure hydrogen product to its maximum since the power consumption for compressing the H2 PSA tail gas up to the gas turbine operating pressure should be minimised to save the total auxiliary power consumption. Hydrogen recovery was raised by increasing the complexity of the PSA step configuration that allows a PSA cycle to have a lower feed flow to one column being used for adsorption and more pressure equalisation steps. An in-depth economic analysis was carried out and discussed in detail. The industrial advanced IGCC performances have also been improved by process integration between the H2 PSA unit and other units in the plant.

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Les piles à combustible, alimentée par de l’hydrogène, représentent une solution prometteuse pour limiter la pollution. L’une des alternatives économiques envisagées à court et moyen terme est de produire l’hydrogène à partir d’un carburant tel que le méthane ou le bio-éthanol. Cette transformation a pour objectif d’obtenir un mélange de gaz riche en hydrogène avec une très faible teneur en CO, ce dernier étant un poison pour les piles de type PEM. La réaction de Water-Gas Shift (WGS) est une étape clé du procédé ; elle convertit CO en CO2 par réaction avec l’eau et fournit une quantité d’hydrogène supplémentaire. Des catalyseurs métalliques (Pt, Pd, Ru, Rh, Au, Cu) supportés sur des oxydes (CeO2, TiO2, ZrO2, Fe2O3, CeO2/Al2O3) ont été comparés dans des conditions de WGS identiques en présence de CO2 et H2. Une étude cinétique a été réalisée sur les catalyseurs Pt/CeO2, Au/CeO2, Pt/TiO2 et Au/TiO2. Les énergies d’activation apparentes et les ordres de réaction ont été déterminés à partir d’un modèle de type loi de puissance. Un mécanisme réactionnel avec deux sites a été proposé pour décrire les différentes activités des 4 catalyseurs. Des expériences de désorption programmée en température ont été réalisées pour déterminer les paramètres cinétiques sur le support / The Fuel Cells are promising solution to reduce the air pollution. One of the cost-efficient alternatives is to produce hydrogen from another fuel such as methane or bio-ethanol. A hydrogen fuel processor consists in generating a hydrogen-rich mixture and reducing the carbon monoxide content, as PEM fuel cells are very low CO tolerance. One of these units is the water-gas shift reactor, which converts CO into CO2 by the reaction with water and provides additional hydrogen. Catalysts based on a metal (Pt, Pd, Ru, Rh, Au, Cu) supported on an oxide (CeO2, TiO2, ZrO2, Fe2O3, CeO2/Al2O3) were compared for the WGS reaction in the same conditions and in the presence of CO2 and H2. A kinetic study was conducted on catalysts Pt/CeO2, Au/CeO2, Pt/TiO2 and Au/TiO2. A power law rate model was used to determine apparent activation energies and reaction orders. A dual-site reaction mechanism was proposed to explain the different activities between the four catalysts. The sorption parameters of H2O and CO2 on the supports was quantitatively determined from temperature-programmed desorption experiments