A novel metal–organic coordination compounds derived carbon for efficient cadmium ion removal: Enhanced performance through oxygen functional groups

• Published in: Separation and purification technology 2025-06, Vol.359, p.130668, Article 130668
• Main Authors: Zhang, Hongwei, Xing, Libin, Ding, Wei, Liu, Shuzhi, Liang, Hongxu, Geng, Zengchao, Xu, Chenyang
• Format: Article
• Language: English
• Subjects: Adsorption; Cd(II); Metal-organic coordination compounds; Oxygen functional groups
• ISSN: 1383-5866
• DOI: 10.1016/j.seppur.2024.130668

[Display omitted] •MOCC@C achieves a removal rate of 99.26 % for a 100 mg/L Cd solution.•Solvent-free MOCC@C synthesis reduces environmental impact and costs.•MOCC@C removes Cd(II) via electrostatic attraction, precipitation, and complexation.•Cd(II) binds MOCC@C in the order: Fe-OH, C = C/C = O, O-C = O.•MOCC@C’s efficiency and low cost make it ideal for wastewater treatment. In recent years, the application of carbon materials derived from metal-organic coordination compounds (MOCCs) has encountered challenges due to the dependence on expensive metals and harmful organic solvents. To overcome these obstacles, this study synthesized an iron-based MOCC precursor using cost-effective ferric chloride as the metal source. A derivative carbon of MOCC (MOCC@C) was prepared by high-temperature activation method and used as an adsorbent material. This method replaces traditional organic solvents with pure water, reducing environmental impact and significantly lowering production costs to just $7.52 per kilogram—considerably less than comparable high-performance adsorbents. MOCC@C was characterized, and its Cd(II) adsorption capacity was assessed through batch experiments. Results revealed that MOCC@C achieved a Cd(II) removal rate of 99.26 %, marking a 6.38-fold improvement over the original MOCC. This exceptional adsorption performance is attributed mainly to the abundance of oxygen-containing functional groups in MOCC@C, which engage with Cd(II) in the order: Fe-OH, C = C/C = O, and O-C = O. Furthermore, MOCC@C successfully removed Cd(II) to meet discharge standards and demonstrated reusability for up to five cycles. Overall, MOCC@C emerges as a cost-effective and environmentally sustainable Cd(II) adsorbent, offering a viable solution for wastewater treatment.