Removal of pertechnetate from aqueous solution using activated pyrolytic rubber char

Low-cost adsorbents, synthesized by pyrolysis of waste rubber (CR) and activated with KOH (CRA), have shown the high removal ability of from aqueous solutions in wide range of pHs (2-10) with fast adsorption rate. The Langmuir and Freundlich models suggests monolayer and multilayer adsorption of onto CR and CRA surface, respectively. The removal mechanism of from solution occurs by replacement with OH- from surface groups (phenolic and/or accompanying carboxylic) of CR and CRA indicating anion exchange mechanism

Sorption and desorption of pertechnetate on biochar under static batch and dynamic conditions

The objective of this study was the utilization of three different biochars for pertechnetate removal from aqueous solutions. Biochars were prepared by slow pyrolysis from different feedstocks, characterized by BET, acid-base titration, SEM, XRD and FTIR and tested for their pertechnetate sorption using batch and dynamic techniques. Effect of various physico-chemical parameters such as contact time, pH and the presence of different ions in the solution on the sorption of pertechnetate onto biochars was investigated. Perrhenate as an analogue of pertechnetate was used for modeling of adsorption isotherms