Chế độ động trong phản ứng Ozonation trực tiếp Trong chương này, động học của phản ứng ôzôn trực tiếp trong nước được xử lý cụ thể, xem xét các chế độ động học khác nhau mà các phản ứng ôzôn hiện tại. Mục tiêu chính của ozonation động học tập trung vào việc xác định các thông số, chẳng hạn như là hằng số tốc độ phản ứng và hệ số chuyển hàng loạt. Như là một bước đầu tiên, cách để ước tính tài sản ozone và liên tục hòa tan hoặc cân bằng (Henry của pháp luật) được. | 5 Kinetic Regimes in Direct Ozonation Reactions In this chapter the kinetics of the ozone direct reactions in water is treated in detail considering the different kinetic regimes that ozone reactions present. The main objective of ozonation kinetics focuses on the determination of parameters such as rate constants of reactions and mass-transfer coefficients. As a first step ways to estimate the ozone properties and solubility or equilibrium constant Henry s law are presented since this information is fundamental to the discussion of any ozonation kinetics. As already indicated in Chapter 3 the direct reaction between ozone and a given compound B that will be treated here corresponds to the stoichiometric Equation that is an irreversible second-order reaction first-order with respect to ozone and B with z moles of B consumed per mol of ozone consumed. However as far as kinetic regimes are concerned the ozone decomposition reaction as first-order kinetics will also be studied. DETERMINATION OF OZONE PROPERTIES IN WATER As observed from the absorption rate law equations deduced in Chapter 4 some properties of both ozone and the reacting compound B should be known to carry out any ozonation kinetic study. These properties are the diffusivity and solubility or equilibrium concentration of ozone in water CA that is intimately related to the Henry s law constant He. Diffusivity Diffusivities of compounds in water can be determined from different empirical correlations. For very dilute solutions the equation of Wilke and Chang1 can be used DA X 10-12 MW 1 2 T kVa0 6 where DA is in m2sec-1 T in K fS an association parameter of the liquid which is for water MW and m the molecular weight and the viscosity of the solvent in poises respectively and VA the molar volume of the diffusing solute in cm3molg-1 that can be obtained from additive volume increment methods such as that of Le The use of Equation in aqueous systems leads to an average .
