New adsorbents for butadiene removal from liquid and gas streams, which are transition metal (Cu, Zn, Mn) polycation exchanged zeolites, were prepared on the basis of low-silica and dealuminated faujasites by ion exchange with the corresponding salt solutions at the conditions of their partial hydrolysis. Obtained samples were characterized by XANES, ESR, and DRIFT spectroscopy along with equilibrium and dynamic adsorption studies. It is shown that transition metal polycation containing faujasites significantly surpass monocation analogues with respect to butadiene adsorption capacity. It is also found that an enhanced ability to adsorb butadiene is peculiar to faujasites with strong acidity that defines the activity of the adsorbent in the oligomerization of adsorbed butadiene. The suggested adsorbents are fully regenerable at gradual elevation of regeneration temperature up to 250–350 °C.

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The reactive adsorption of sulfur‐contaminated compounds over transition metal (TrM) polycation‐exchanged zeolites is a very efficient method for the desulfurization of hydrocarbon processing streams. The process consists of the physical adsorption of thiols, sulfides, and disulfides and the catalytic oxidation of the adsorbed substances. The reaction does not require the participation of free oxygen; diffuse‐reflectance infrared Fourier transform spectroscopy (DRIFTS) and X‐ray absorption spectroscopy (XAS) studies confirmed that the thiol oxidation proceeds through the direct involvement of TrM polycation superoxides. All of the studied zeolite X, zeolite Y, and mordenite materials containing Zn, Mn, Cu, and Cd polycations show remarkable activity for the oxidation of sulfur compounds; this results in a significant increase of the total pick‐up from gas and liquid hydrocarbons. The thermal regeneration of the adsorbent–catalysts under oxidizing conditions leads to the complete restoration of their original activities and capacities for the removal of sulfur compounds. Suitable operating conditions for the regeneration process are disclosed. The study also demonstrates favorable properties of the suggested adsorbent–catalysts for use in commercially important applications such as the desulfurization of natural gas and liquid hydrocarbons.