Tetrachloromethane (TCM) and 1,1,2,2-tetrachloroethane (TChE) were oxidized in the temperature range from 300 to 600°C and at contact time of 0.36 s. The following catalysts were applied during the process: the granular one - platinum (0.12%) at the TiO2-SiO2 carrier, platinum ZChO-80 (0.15%) at γ-Al2O3 carrier, palladium (1%) at γ-Al2O3 carrier and monolithic platinum-rhodium catalyst (Pt - 0.09% and Rh - 0.04%) at the cordierite carrier.
The substrates were oxidized in the presence of the above mentioned catalysts with various efficiencies depending on the molecular structure and the type of the catalyst. Palladium contact appeared to be the most active among the others. In the presence of this catalyst, total oxidation of TCM and TChE proceeded at the temperature of 425 and 500°C, respectively. The content of PCDD/Fs in gaseous products obtained during the oxidation of both substrates, was significantly lower than the admissible value of the toxicity equivalent (0.1 ng TEQ/m3).
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