Recuperación de hidrógeno de mezclas gaseosas mediante un proceso PSA

Abstract

This PhD work has been done in the CyPS group (Catalysis and Separation Processes Group). This group belongs to the Chemical Engineering Department at the Faculty of Chemical Sciences of the Complutense University of Madrid. It is based on a research study in the field of hydrogen purification by cyclic PSA (Pressure Swing Adsorption) processes. The study has focused on mixtures in which hydrogen is the main compound, with methane, carbon monoxide and carbon dioxide as its main impurities.Today, natural gas present in oilfields provides our main source of hydrogen. The process by which hydrogen is obtained is called SMR (Steam Methane Reforming). This process involves the catalytic oxidation of methane through water vapour. This gives rise to a gas mixture that contains mainly hydrogen and carbon dioxide, as well as unreacted methane, and carbon monoxide. The purification of the hydrogen obtained is due to the need for a product of high purity, be it for commercialisation or for other reasons, such as the importance of reducing the concentration of CO at the ppm concentration level, since this can be a poison to catalysts in some cases.The most commonly used purification process for the recovery of hydrogen from the mixture that is obtained after SMR is the PSA process, which is a separation operation based on adsorption. The PSA cycle consists in the purification of hydrogen from the mixture, retaining the impurities that accompany it in a bed of adsorbent particles. The key to the process lies in the influence of pressure on adsorption...