Kinetic study of the hydrodechlorination of trichloroethene in water using a platinum catalyst and hydrazine.
Column experiments were used to measure the hydrodechlorination rate of relatively high concentrations of trichloroethene (TCE) (approximately 100 mg L(-1)). Trichloroethene in water was treated with a platinum on titania (Pt-TiO2) catalyst and hydrazine. The influence of some experimental conditions (i.e., flowrate, temperature, and pH) on the catalytic conversion of TCE was studied. The pseudo-first-order rate constant of the overall hydrodechlorination of TCE was approximately 1 x 10(-3) to 1 x 10(-2) s(-1) in the temperature range of 283 to 328 K and was determined from the dependence of the TCE conversion on the contact time of the feed water with the catalyst by assuming first-order kinetics. The activation energy of the catalytic hydrodechlorination of TCE was calculated as approximately 34 kJ/mol from the temperature dependence of the rate constant. The TCE conversion increases with increasing pH, and probably correlates with the presence of un-ionized hydrazine.
Faculty of Education, Toyama University, Japan. miyabe@ach.nitech.ac.jp
Kanji
K
Miyabe
Norie
N
Taniguchi
Aiko
A
Imura
Yoshisato
Y
Tezuka
D002273:Carcinogens / Q000737:chemistry; D002384:Catalysis; D006834:Hydrazines / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010984:Platinum / Q000737:chemistry; D012997:Solvents / Q000737:chemistry* / Q000302:isolation & purification; D013696:Temperature; D014025:Titanium / Q000737:chemistry; D014241:Trichloroethylene / Q000737:chemistry* / Q000302:isolation & purification; D014865:Waste Disposal, Fluid; D014872:Water Movements; D018508:Water Purification / Q000379:methods*
D002273:Carcinogens; D006834:Hydrazines; D012997:Solvents; C009495:titanium dioxide; C029424:hydrazine; D014241:Trichloroethylene; D010984:Platinum; D014025:Titanium