High-efficiency removal of Cr(VI) and rhodamine B in wastewater via nano-zero-valent iron reduction and Fenton reaction

BACKGROUND The treatment of industrial wastewater containing chromium (Cr(VI)) and rhodamine B (RhB) is a critical environmental protection issue. Fenton-like systems have been widely considered for their potential in wastewater treatment, but developing efficient and practical Fenton-like materials and methods remains a key challenge. This study focuses on exploring the effectiveness of a Fenton-like system composed of a zero-valent iron-based composite material (HTCTSIP-5) and exogenous hydrogen peroxide (H₂O₂) for the removal of Cr(VI) and RhB from wastewater. RESULTS The effects of various parameters, including dosing methods, pH levels, content of HTCTSIP-5 and H₂O₂, and initial concentrations, on the removal efficiency were studied. Techniques such as electron paramagnetic resonance, scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy were employed to investigate the underlying mechanisms of removal of Cr(VI) and RhB. The results revealed that the HTCTSIP-5/H₂O₂ system exhibited high removal efficiencies for both Cr(VI) and RhB, with hydroxyl radicals ( • OH) identified as the key agents in RhB degradation. CONCLUSION This study confirms that the use of the HTCTSIP-5/H₂O₂ Fenton-like system is an effective approach for the treatment of wastewater containing Cr(VI) and RhB. It provided an effective material and method for industrial wastewater treatment, offering a valuable approach for environmental protection. © 2026 Society of Chemical Industry (SCI).