Structural changes in phenol-intercalulated hydrotalcite caused by heating
Abstract:Thermal analysis (DTA-TG-DTG), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, nitrogen adsorption and mercury intrusion porosimetry techniques were used to assess the structural changes induced upon heating of two hydrotalcite-phenol (trichloro- and trinitrophenol, HT-TCP and HT-TNP) complexes, and the results were compared with those obtained for the original hydrotalcite (HT) sample. The DTA revealed thermal effects that depended on the nature of the interlayer ion in the complexes. The total weight loss (TG-DTA) increased from 37% for the original HT to 40% for HT-TCP and 77% HT-TNP, as the amount of phenol increased. The XRD and FTIR spectroscopy showed that the calcination product (550°C) of the HT-phenol complexes was indistinguishable from that formed from the original HT. Since HTphenol complexes were prepared by phenol adsorption on calcined HT, our results confirm the recyclability of HT-like compounds as sorbents for phenols.
Document Type: Research Article
Publication date: 2000-12-01