N/O-Codoped Biochar: A Solution for Radioactive Iodine Adsorption

N/O-codoped ultrathin porous #biochar, derived from #casein and activated with NaHCO3, effectively adsorbs #radioactiveiodine, reaching 73 mg·g–1 in 20 minutes. The biochar’s graphite nitrogen and C–OH groups enhance adsorption, primarily via physisorption, offering a promising solution for environmental radioactive iodine contamination.

July 22, 2024

1–2 minutes

Wang, et al (2024) N/O-Codoped Ultrathin Porous BiocharBiochar is a carbon-rich material created from biomass decomposition in low-oxygen conditions. It has important applications in environmental remediation, soil improvement, agriculture, carbon sequestration, energy storage, and sustainable materials, promoting efficiency and reducing waste in various contexts while addressing climate change challenges. More Derived from Casein for Fast Adsorption of Iodine. *Langmuir.* https://doi.org/10.1021/acs.langmuir.4c01487

Radioactive iodine contamination in the environment is a serious issue, affecting soil, water, and food chains, and thereby impacting ecosystems and biodiversity.

A promising method for tackling this problem is using N/O-codoped ultrathin porous biochar for adsorption. This biochar, derived from casein and activated with NaHCO3, has shown a high saturation level of iodine adsorption, reaching 73 mg·g–1 in a 100 mg L–1 iodine–cyclohexane solution within 20 minutes. The effectiveness is attributed to graphite nitrogen (NG) and C–OH groups on the biochar’s surface, with DFT calculations and experiments supporting this finding.

The adsorption process is primarily physisorption-based, fitting well with the pseudo-first-order model, and the Freundlich isotherm due to the biochar’s abundant adsorption sites. Notably, NG sites are 1.5 times more effective than C–OH sites, highlighting their crucial role in iodine adsorption and electron transfer. This study demonstrates the potential of N/O-codoped biochar in mitigating radioactive iodine contamination.