Assessment of Pyrogenic Carbonaceous Materials for Effective Removal of Radiocesium

Pyrogenic carbonaceous materials produced by pyrolysis process of various waste feedstocks are increasingly used in non-soil applications such as water purification tools. Pyrogenic carbonaceous materials thermochemically converted from wood chips, corn cobs, garden green waste, cherry pits, walnut shells, pine cones and municipal sewage sludge in slow pyrolysis under N2 atmosphere, were characterized by total C analysis, specific surface area, volumes of micro- and mesopores and tested in batch experiments as potential radiocesium sorption materials. Cesium adsorption-desorption experiments were conducted using the 137Cs radioisotope. Although tested materials significantly differ in Cs removal, Cs+ ions uptake could be attributed to the mechanisms of Freundlich surface adsorption. The highest maximum sorption capacities were reached for pine cones, wood chips and garden waste pyrogenic materials and reached 95.9 to 126 μmol g-1. These results demonstrate suitability of selected Pyrogenic carbonaceous materials as Cs adsorbents potentially useable as reactive barriers for 137Cs contaminated effluents.