Flame-made High-Capacity and High Efficient Nanomaterial CuOx-CeOx-WO3/TiO2 for Mercury Adsorption

High -concentration mercury capture at high temperatures poses a significant challenge during the periodic shutdown of raw meal mills in cement clinker production. This study synthesized CuOx-CeOx-WO3/TiO2 nanomaterials for mercury removal using wet impregnation, laminar premixed flame (-1800 K), and flame spray pyrolysis (FSP, - 2800 K). The performance of the synthesized sorbents was evaluated for mercury removal at temperatures above the typical shutdown conditions, specifically at 450 degrees C. The results demonstrated that the FSP-synthesized sorbent maintained an adsorption efficiency of over 95 % even after 30 days of continuous absorption, while the wet -impregnated sorbent reached saturation after only 50 h. To gain insights into the adsorption mechanism, various physicochemical properties of the sorbents were characterized, including surface area, pore volume, average pore diameter, phase composition, morphology, and valence states of surface elements. The findings revealed that the FSP-synthesized sorbent exhibited a larger specific surface area and smaller primary particle sizes compared to the wet -impregnated sorbent. Furthermore, Cu atoms were dispersed within the FSP-synthesized sorbent, while CuO clusters were supported on CeO2 in the wet -impregnated sorbent. Based on the XPS results, it was determined that the FSP-synthesized sorbent utilized adsorbed molecular oxygen as the oxidizing species, whereas the wet -impregnated sorbent relied on active oxygen on the CeO2 surface.