Kinetic models for volatile chlorinated hydrocarbons removal by zero-valent iron

Kinetic models for removal of trichloroethylene, trichloromethane and tetrachloroethylene from water by zero-valent iron were tested. The dehalogenation reactions were modelled by first-order and power law models, pseudostationary models with a controlling surface reaction rate and non-stationary models without the assumption of rate controlling step. Regression analysis proved, that the first-order kinetic is not suitable for the modelling of chlorinated hydrocarbons dechlorination. On the other hand, power law models, Langmuir Hinshelwood analogy models and general models of heterogeneous reactions are reliable for the kinetic description of dechlorination. In spite of an empirical or semi-empirical character, the power law models and models of controlling surface reaction rate can be recommended for the regression analysis owing to the their simple regression parameters interpretation. (C) 2003 Elsevier Ltd. All rights reserved.