MODIFICATION OF a-Cr2O3 BY KCI FOR WATER TREATMENT APPLICATION

The starting material Cr203 was prepared by thermal decomposition of bichromate salts and followed by thermal shock with molten KCl at 800°C in varied periods. XRD data indicated modified samples were still a-Cr2O3 without any trace of other phases. XPS data showed a trace amount of Cl on surface. The agglomerated particles were relatively uniform. The modified samples had a higher catalytic activity than the initial samples. For oxidation of Red Congo by air, the conversion reached 95,08% for modified samples as compared with 69,80% for initial samples and 0,81% if no catalyst was used. For treatment water from Nhiêu Lộc canal (Thị Nghè, HCMC), best result was obtained after 3 day treatment, COD of waste water diminued to 9,84 mg 02/L.