The infrared spectra of the adsorbent in KBr pellets were
recorded on the FTIR Spectrometer FSM 1202 (Infraspek Ltd., Saint
Petersburg, Russia). The KBr pellets were prepared under 200 bar
pressure for 8 min. The spectrawere recorded by accumulation of at
least 32 scans, the resolution being 4 cm1. Bands were identified
according to Kumirska et al. (2010).