Tailoring photocatalytic activity of graphitic carbon nitride using sulfanilic acid and incorporating in chitosan beads: Cr(VI) removal from aqueous solutions

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) Vol. 130; pp. 412 - 424
• Main Authors: Masoumi Sangani, Mohammad Mahdi, Shahin, Mohammad Sajjad, Yavari, Mohammad Ali, Faghihinezhad, Mohsen, Baghdadi, Majid
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.02.2024; 한국공업화학회
• Subjects: Chitosan; Graphitic carbon nitride; Groundwater treatment; Hexavalent chromium removal; Photocatalyst; 화학공학; Hexavalent chromium removal; Chitosan; Photocatalyst; Groundwater treatment; Graphitic carbon nitride
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2023.09.047

[Display omitted] •96% of Chromium hexavalent in groundwater was removed at pH = 2 in 60 min.•The Melamine/Sulfanilic acid mass ratio of 10 resulted in the best performance.•The application of sulfanilic acid enhanced the electron transmission.•The activity was highly enhanced as the band gap fell from 2.7 to 2.4 eV.•The nanocomposite also possesses great reusability after 5 cycles. The existence of hexavalent chromium in groundwater has been considered a global concern due to its toxicity, and carcinogenicity, which can threaten human life. In this study, groundwater containing chromium hexavalent was treated by graphitic carbon nitride modified with sulfanilic acid, which was incorporated in chitosan beads (CS-GCN-S). The characterization of the nanocatalysts was performed by the relevant technique, including Field-Emission Scanning Electron Microscopy (FESEM), X-Ray Diffraction (XRD), Diffuse Reflection Spectroscopy (DRS), Fourier Transform Infrared (FTIR) Spectroscopy, Brunauer-Emmett-Teller (BET), electrochemical impedance spectroscopy (EIS) and inductively coupled plasma (ICP) analysis. The melamine/sulfanilic acid mass ratio was optimized at 10. The added optimal content of sulfanilic acid and chitosan enhanced the functionality of graphitic carbon nitride as well as boosted adsorption and photocatalytic activity. A considerable increase in photocatalytic activity under visible light is indicated by the band gap's decline from 2.7 to 2.4 eV, as determined by DRS analysis. The greatest efficiency (94%) was found at a pH of 5 and a catalyst dosage of 1 g/L after the effects of pH, catalyst dosage, and starting Cr(VI) concentration were examined. Up to five cycles of the catalyst's performance evaluation revealed a slight (10%) performance decline.