Review: Advances in efficient separation of paraxylene from mixed xylene isomers using SMB technology and MOF materials

Abstract

In recent years, the global demand for paraxylene (PX) has increased significantly, prompting extensive research into the refinement of the SMB adsorption process and the selection of optimal adsorbent materials. This paper provides a comprehensive overview of advancements in SMB technology, particularly focusing on developments in scrubbing strategies and modeling over the past few years. Unlike other processes, SMB technology leverages the differential adsorption capacities of components in a mixture across mobile and stationary phases, achieving PX purities as high as approximately 99.7%. The paper also reviews recent progress in the use of MOFs as adsorbents for the separation of xylene isomers, discussing aspects such as adsorption capacity, selectivity, and the underlying separation mechanisms. Compared to traditional adsorbent materials, MOFs offer adjustable pore structures, high surface areas, flexible main body structures, and a variety of species, demonstrating high selectivity coefficients and stable adsorption performance in xylene separation experiments. Overall, MOFs present promising prospects for use in the SMB adsorption process. Consequently, this paper reviews both the production and separation of PX using SMB technology and the advancements in MOFs as adsorbent materials, anticipating their significant impact on future research.