Abstract
In this work, hexagon-shaped potassium ferrite (K2Fe4O7) crystals with different sizes were prepared using the hydrothermal method. The crystals showed a narrow band gap of 1.44 eV, revealed by UV-visible diffuse reflectance spectroscopy, and was thus used as a heterogeneous Fenton catalyst to degrade methylene blue (MB) and crystal violet (CV) in the presence of green oxidant H2O2 under visible-light irradiation. Among the investigated crystals, the as-prepared one with an average size of 20 µm (KFO-20) exhibited better photocatalytic activity due to its high surface area. When it was used as a photo-Fenton catalyst, 100% MB and 92% CV were degraded within 35 min. Moreover, the catalyst maintained high photocatalytic activity and was stable after four continuous cycles. The trapping experiments showed that the active hydroxyl radical (·OH) was dominant in the photo-Fenton reaction. Therefore, this new photo-Fenton catalyst has great potential for the photocatalytic degradation of dye contaminants in water.
Highlights
Dyes are widely used in many industries, including textiles, printing, pulp, and paper
Over the past few decades, many wastewater-treatment technologies have been developed for the removal or degradation of dye contaminants, such as traditional biological treatments, adsorption, coagulation/flocculation, membrane separation, precipitation, ion exchange, and advanced oxidation processes (AOPs)
We found that crystallinity contributed little to Methylene blue (MB) degradation comparing to the specific surface area
Summary
Dyes are widely used in many industries, including textiles, printing, pulp, and paper. Over the past few decades, many wastewater-treatment technologies have been developed for the removal or degradation of dye contaminants, such as traditional biological treatments, adsorption, coagulation/flocculation, membrane separation, precipitation, ion exchange, and advanced oxidation processes (AOPs). Among these methods, AOPs that include photochemical, catalytic, sonochemical, ozone, electrochemical, and Fenton oxidation can convert or degrade such contaminants into small molecules [5,6,7]. To overcome these drawbacks, one potential strategy is using heterogeneous photo-Fenton catalysts to degrade dye contaminants. Several iron oxides and Catalysts 2020, 10, 293; doi:10.3390/catal10030293 www.mdpi.com/journal/catalysts
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
