ARTICLE pubs.acs.org/IECR
Adsorption Measurements of Nitrogen and Methane in Hydrogen-Rich Mixtures at High Pressures Moises Bastos-Neto,† Andreas Moeller,*,† Reiner Staudt,‡ J€urgen B€ohm,§ and Roger Gl€aser†,§ †
Institut f€ur Nichtklassische Chemie eV, Permoserstrasse 15, 04318 Leipzig, Germany Fakult€at Maschinenbau und Verfahrenstechnik (M+V), Hochschule Offenburg, Badstrasse 24, 77652 Offenburg, Germany § Institut f€ur Technische Chemie, Universit€at Leipzig, Linnestrasse 3, 04103 Leipzig, Germany ‡
ABSTRACT: The separation of nitrogen and methane from hydrogen-rich mixtures is systematically investigated on a recently developed binder-free zeolite 5A. For this adsorbent, the present work provides a series of experimental data on adsorption isotherms and breakthrough curves of nitrogen and methane, as well as their mixtures in hydrogen. Isotherms were measured at temperatures of 283313 K and pressures of up to 1.0 MPa. Breakthrough curves of CH4, N2, and CH4/N2 in H2 were obtained at temperatures of 300305 K and pressures ranging from 0.1 to 6.05 MPa with different feed concentrations. An LDF-based model was developed to predict breakthrough curves using measured and calculated data as inputs. The number of parameters and the use of correlations were restricted to focus on the importance of measured values. For the given assumptions, the results show that the model predictions agree satisfactorily with the experiments under the different operating conditions applied.
1. INTRODUCTION Even though it is not a primary energy source, hydrogen needs to be produced and consequently purified. The current main source of hydrogen is the processing of fossil derivatives such as methane, coal, and heavy hydrocarbons. Other sources include electrolysis and biological processes.13 Hydrogen is most commonly produced through the steam reforming of natural gas combined with the watergas shift reaction, from which a hydrogen-rich stream (7080%) containing impurities, namely, hydrogen sulfide (traces), water vapor (
