Title : Development and characterization of a new dolomite-based catalyst: Application to the photocatalytic degradation of pentachlorophenol
Abstract:
The development of new catalysts from abundant raw materials, generating attractive photocatalysts, constitutes a real challenge in the context of sustainable development. In this setting, a dolomite was treated at 800 °C (D800) and then chemically modified by Ca(NO3)2 (CaD800) using a simple procedure solution. The resulting materials were characterized by X-ray diffraction, electron scanning microscopy, energy dispersive X-ray spectroscopy (EDS), solid-state UV spectroscopy, and used as degradation catalysts. pentachlorophenol (PCP) in aqueous solutions under UV light irradiation. The treatment of dolomite at 800 °C allowed complete decarbonation of CaMg(CO3)2, with the formation of CaO, Ca(OH)2 and MgO. Additional CaO was generated after chemical treatment, as revealed by EDS analysis; the Ca/Mg ratio increased from 1.29 (D800) to 1.44 for CaD800. This CaO in an aqueous medium hydrates giving Ca(OH)2. CaD800 was found to be the best photocatalyst with a PCP degradation rate of 95%. after only 1 hour of treatment, for a constant CaD800/D800 degradation rate ratio of 1.58. In this regard, we studied the Fourier infrared spectra of CaD800, PCP, and PCP-loaded CaD800 after degradation. We therefore highlighted the involvement of Ca(OH)2 in the PCP degradation process. Catalytic was discussed through the contribution of OH radicals and electrodonation.
