Natural Hematite and Siderite as Heterogeneous Catalysts for an Effective Degradation of 4-Chlorophenol via Photo-Fenton Process

Abstract

This paper describes a simple and low-cost process for the degradation of 4-Chlorophenol (4-CP) from aqueous solution, using natural Tunisian Hematite (M 1 ) and Siderite (M 2 ). Two natural samples were collected in the outcroppings of the Djerissa mining site (Kef district, northwestern Tunisia). Both Hematite and Siderite ferrous samples were characterized using several techniques, including X-Ray Diffraction (XRD), Nitrogen Physisorption (BET), Infrared Spectroscopy (FTIR), H 2 -Temperature Programmed Reduction (H 2 -TPR), Scanning Electronic Microscopy (SEM) linked with Energy Dispersive X-ray (EDS) and High-Resolution Transmission Electron Microscopy (HRTEM). Textural, structural and chemical characterization confirmed the presence of Hematite and Siderite phases with a high amount of iron on the both surface materials. Their activity was evaluated in the oxidation of 4-CP in aqueous medium under heterogeneous photo-Fenton process. Siderite exhibited higher photocatalytic oxidation activity than Hematite at pH 3. The experimental results also showed that 100% conversion of 4-CP and 54% TOC removal can be achieved using Siderite as catalyst. Negligible metal leaching and catalyst reutilization without any loss of activity point towards an excellent catalytic stability for both natural catalysts.

Reduced Siderite Ore Combined with Magnesium Oxide as Support Material for Ni-Based Catalysts; An Experimental Study on CO2 Methanation

“…Use of the siderite catalyst gave 100% conversion of 4-CP and 54% TOC removal. In terms of the removal of several organic compounds in an aqueous condition, the work confirmed that natural materials can be used as catalysts [60]. Wei et al used siderite (doped with Mn and Ce) for the selective catalytic reduction (SCR) of NO x by NH 3 .…”

Heterogeneous Photocatalysis

“…The photo-Fenton reaction has been described by many authors as one of the most promising ways to remove highly hazardous organic species. In this special issue, natural Tunisian materials containing very important amounts of iron were reported as catalysts for an effective degradation of 4-Chlorophenol via the photo-Fenton process in a contribution by Bel Hadjltaief, Elena Gálvez et al The Negligible metal leaching and catalyst reutilization results without any loss of activity confirmed a remarkable catalytic stability of natural catalysts, opening a new window in the materials field for this application [19].…”

Magnetite, Hematite and Zero-Valent Iron as Co-Catalysts in Advanced Oxidation Processes Application for Cosmetic Wastewater Treatment

“…Both strategies pose numerous technical difficulties when applied in practice; therefore, iron-based heterogeneous cocatalysts are gaining interest. Among them are Fe 0 (metallic iron, zero-valent iron, ZVI), Fe 2 O 3 (hematite), and Fe 3 O 4 (magnetite) [28][29][30][31]. Oxides act through coordinating surface sites of Fe 2+ that form complexes with contaminants and reduce them [28].…”