Reactive adsorption of low concentration methyl mercaptan on a Cu-based MOF with controllable size and shape

Abstract

A copper-based metal organic framework (MOF-199) with controllable size and shape was synthesized and used to remove gaseous methyl mercaptan (CH₃SH). Characterizations of the synthesized MOF-199 samples before and after desulfurization were carried out by X-ray diffraction (XRD), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) to observe the adsorption mechanism of CH₃SH on MOF-199. The adsorption performance of the synthesized MOF-199 materials and commercialized activated carbon (AC) and Cu loaded AC were evaluated by breakthrough experiments. All three synthesized MOF-199 materials show better performance than commercialized AC. The morphology and texture of MOF-199 materials have great influence on the performance of the adsorption process. The MOF-199 material synthesized by a hydrothermal method exhibited the highest sulfur compound capacity among the synthesized MOF-199 materials (74.7 mg of CH₃SH/1 g MOF-199). The color change of MOF-199 during the CH₃SH capturing process, indicated a strong interaction between the unsaturated copper sites and –SH group which finally formed CuS and gave rise to obvious damage to the MOF structure.