High capacity laminate adsorbers: Enhancing separation performance beyond packed beds

Abstract

In response to the growing demand for more efficient adsorption processes, structured adsorbents have emerged as a promising solution as they offer improved mass transfer and pressure drop characteristics. However, they are often hampered by a lower volumetric capacity due the presence of support structures or a large bed void fraction. This research focuses on the manufacturing and evaluation of self-standing zeolitic laminates of various thickness and spacing, comparing their performance to a traditional packed bed. A shaping method to obtain laminates with a 84 wt% zeolite 13X content is described. Furthermore, a method for precise assembly and spacing of the laminates is detailed. Three such laminar adsorbers with different geometries were evaluated in breakthrough experiments and compared to a packed bed to assess their efficiency in the bulk separation of carbon dioxide. Superior performance of the laminar adsorbers was found, with one configuration employing 1.2 mm laminates and 0.4 mm spacing showing a significant 19 % increase in volumetric capacity compared to a packed bed of pellets. This enhanced capacity is achieved while maintaining efficient heat and mass transfer, resulting in sharp breakthrough profiles. Furthermore, using thinner (0.5 mm) laminates, the length of unused bed was further reduced. Additionally, pressure drop calculations were performed and experimentally validated. The pressure drop over the laminar adsorbers was shown to be significantly lower than over a packed bed. These findings underscore the potential of laminar adsorbers to intensify adsorptive separation processes, reduce energy consumption, and address the demand for more effective adsorption technologies.