Metal-Modified Cu-BTC Acid for Highly Enhanced Adsorption of Organosulfur Species

In this study, we provide an approach to the tunable metal modification on Cu-BTC (BTC= 1,3,5-benzenetricarboxylic acid) in order to achieve a highly enhanced adsorption affinity toward organosulfur species. We propose a strategy to regulate the metal compositions via the well-controlled reduction of Cu(II) to Cu(I) in Cu-BTC using ethanol as the reducing agent coupled with loaded Ag as catalyst under mild conditions. Applying scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS), we confirmed the successful modification and explored their structural changes. The quantitative relationship between metal compositions of Cu-BTC samples and their adsorption capacities for organosulfur compounds including dimethyl disulfide (DMDS), ethyl sulfide, and 1-propanethiol were highlighted, and the underlying adsorption mechanism was elucidated. Present results have significant implications for the optimal design and manipulation of the compositions as well as structures of metal–organic porous materials for adsorption desulfurization and better understanding of the role of metal species in sulfide adsorption.