Effect of Calcination Temperature on Catalytic Performance of CeCu Oxide in Removal of Quinoline by Wet Hydrogen Peroxide Oxidation from Water

Abstract

A facile citric acid-mediated complexation-calcination approach is reported in this paper to prepare the CeCu oxide composite with a porous structure that is highly efficient and durable for treating simulated quinoline wastewater by catalytic wet hydrogen peroxide oxidation (CWPO). As the results indicate, Cu species can be dissolved in CeO 2 lattice to fabricate a solid solution. The calcination temperature is critical for an optimum catalyst structure and catalytic performance. As found in investigating the structure and catalytic performance of the CeCu oxide prepared at calcination temperatures ranging from 350 to 750 °C, the optimum temperature is 650 °C, at which a loose surface, a porous structure and considerable adsorbed surface oxide/hydroxyl oxide species are fabricated over the catalyst. This resultant catalyst also takes on the optimal performance with an oxidation conversion reaching 98% for quinoline, a removal efficiency of 80.6% for total organic carbon (TOC) and a low Cu 2+ leaching value of 19.3 mg L -1. Besides, the high performance is maintained by the catalysts in a wide pH range of 5.1-10.5. This work generally provides an efficient way to design and fabricate the catalyst for CWPO reaction, which can also be applied in other reactions.

Degradation of Bisphenol A by CeCu Oxide Catalyst in Catalytic Wet Peroxide Oxidation: Efficiency, Stability, and Mechanism

“…The crystalline phase structure, pore structure, and surface morphology of the catalyst did not change significantly before and after the reaction. On the one hand, it may have been due to the fact that Cu 2+ dissolved into the CeO 2 lattice to form CeCu oxide solid solution, which resulted in strong interaction between CuO and CeO 2 and enhanced the stability of the catalyst; on the other hand, it may be due to the addition of rare earth element Ce, which can disperse and stabilize the active components of the catalyst and improve its acidity resistance and prevent volume shrinkage, thereby improving the structural stability of the catalyst to a certain extent [30].…”

“…The peaks ranging from 529.8–531 eV belonged to the absorption oxygen O 2 2− or O − species on the catalyst surface. The peak at 531.6 eV was from the hydroxyl oxygen OH − [30] of absorbed water on catalyst surface. From the comparison of O1s XPS spectra before and after the reaction, the O1s XPS peak of CC450 catalyst shifted slightly to the right after five reuses, indicating that lattice oxygen content was gradually dominant and stable crystal phase CuO might gradually form on the catalyst surface, with some loose amorphous species lost along with the reaction.…”

“…According to the degradation pathway, CeCu oxide catalysts in heterogeneous CWPO reaction system may have mainly produced strong oxidative ·OH radicals by catalyzing H 2 O 2 to achieve oxidative degradation of organic compounds. It was found that the prepared CeCu oxide catalyst formed a CeCu oxide solid solution at high temperature, and some Cu + and Cu 2+ replaced Ce 4+ in the CeO 2 lattice, which destroyed the coordination balance of CeO 2 lattice and formed a pair of Cu 2+ and Ce 3+ /Ce 4+ ions between CuO and CeO 2 [30], resulting in oxygen vacancy. Oxygen vacancy may be beneficial to the adsorption and activation of H 2 O 2 [25].…”

“…Materials containing Cu 2+ /Cu + , such as iron and other metals, could produce hydroxyl radical in catalyzing hydrogen peroxide, and also have a higher ability to degrade BPA [25]. However, the Cu-based catalyst leads to the loss of active components in the CWPO process, and the preparation process of some catalysts is relatively complicated [24,26,30]. Therefore, this paper intends to prepare a catalyst with simple structure and strong stability, which could also show high catalytic activity and adapt to wide pH ranges.…”

Thermal treatment stimulus on erythrocyte compatibility and hemostatic behavior of one‐dimensional bioactive nanostructures

“…In particulates, beyond relevant sintering, temperature initiates the grain growth and agglomerate formation and aggregation was increased leading to the densification. At the time of calcination, oxidation and reduction takes place, which encourages the removal of water and gas phases together with impurities (Jiao et al, 2018; Rhamdhani, Jak, Hayes, & Nicke, 2008). By varying the sintering temperature, amorphous bioactive glasses turn to semicrystalline nature with the grain growth owing to Ostwald ripening (Carter & Norton, 2007).…”