Characterization of inactivated and activated carbon by FTIR analysis and adsorption experiments

FTIR spectroscopy was used to characterize the carbonaceous material C_N and C_A prepared by pyrolysis from waste rubber. The investigated materials were found to contain phenolic groups, aromatic carboxyl groups or lactone groups. The presence of other oxygen-containing groups was the result of the reaction between carbon and some of the gases - H₂O, CO and CO₂ generated during the pyrolysis. Also, the effect of contact time (5 - 180 min) and influence of pH (pH 2 - 10) on pertechnetate adsorption to non-activated (CN) and activated carbon (C_A) were studied. The aqueous solution was labelled with ^99mTcO₄^- and its pH was adjusted with 1 mol·dm^-3 HCl and 0.1 mol·dm-3 NaOH. Percentage of sorption R % after a short time - 5 min. was high (71% for CN and 98% for C_A). R % for both forms of carbon material was high throughout the pH range (>79% and ∼98% in the case of C_N and C_A), suggesting that ^99mTcO₄^- anionic C_N and C_A adsorption is almost independent of aqueous solutions. Measurement error was less than 5%. (authors)