Highly efficient and nature-based removal of radionuclides from environmental water

Radioactive elements released into the environment have been an imperative environmental issue and poses health hazards for living organisms. Activated carbon is one of the most common adsorbents involved in radioactive wastewater remediation due to its high specific surface area and high degree of surface reactivity. In this study, three alternative activated carbons, previously produced via thermo-chemical activation using phosphorous acid and derived from apricot (Prunus armeniaca), plum (Prunus domestica), and cherry/sour cherry (Prunus avium/Prunus cerasus) kernels were evaluated for their effectiveness in removing radioactive substances. Water from a uranium mine at Žirovski Vrh, characterised by high resolution gamma spectrometry, was chosen for the experiment due to its rather high content of radionuclides, especially uranium. The efficiency of these carbonous materials was compared to a commercial activated carbon. During the experiments the remediation performance was monitored by determination of the gross alpha/gross beta activity, which can be used as fast and cost-efficient screening method for the calculation of decontamination level. Activated carbon from plum kernels showed remarkable achievement lowering alpha and beta activity for 95% and 96%, respectively. Radionuclide removal was most effective under neutral to alkaline conditions, achieving efficiencies > 85% for alpha emitters and > 95% for beta emitters. Desorption was successful with a small amount of 0.1 M H2SO4 and 0.1 M H3PO4, respectively, proving that the tested materials can be used repeatedly for recovery of uranium from waters. Our results emphasised the importance of different alternative carbonous materials potential in radioactive pollutant removal and recovery.