Comprehensive Study of Sorption Materials Based on Sludge from a Treatment Plant for the Capture of Sulfur Compounds from Gas Fuels

The article presents the results of the development of multicomponent adsorption materials based on industrial waste sludge from the water treatment plant of a thermal power plant. Activation of the sludge at 1000 °C makes it possible to obtain a porous matrix. It has been experimentally established that compositions with 50% activated sludge content in combination with oxides of Zn, Fe, Mn, Cu and NaOH have an optimal sorption capacity with respect to hydrogen sulfide. Kinetic studies have shown that the optimal contact time of the adsorbent with the adsorbate is 15–20 min, and the operating temperature should not exceed 300 K. The calculated thermodynamic parameters confirm the exothermic chemical mechanism of sorption. The materials have the ability to regenerate and display a color change upon contact with hydrogen sulfide. With respect to mercaptan sulfur, the maximum capacity was achieved for the sorption composition with 74.7% ZnO content. The logarithmic dependence of the mercaptan sulfur capacity on the percentage of zinc oxide in the composition has also been established. The environmental significance of the work lies in the utilization of large-tonnage waste and the absence of liquid effluents during regeneration. The proposed materials show promise as potentially cost-effective alternatives for gas purification, though comprehensive economic analysis remains the subject of future work.