Kinetics Study and Influence of Ca/Si on Volatilization of CuCl2 in Thermal Process

Abstract

Aimed at the characteristic of MSWI fly ash in China that high content of chlorine, the volatilization of copper chloride (CuCl2) was studied. Firstly, the volatilization experiments of CuCl2 (about 28 mg) were carried out in a high temperature TG-DTA system, the considerable factors included atmosphere (Nitrogen and Air), heating rate (10¿/min, 15¿/min and 20¿/min) and different ratio of CaO/SiO2(mole ratio in 0.6, 0.8, 1.0, 1.2 and 1.4); Subsequently, the intrinsic kinetic model of CuCl2 volatilization was worked out. For experimental study the results show that: Two reaction peaks appeared in TG and DTG curves of CuCl2 volatilization; The volatilization rate of CuCl2 in Air atmosphere are lower than that in Nitrogen atmosphere obviously; The changing tendency of volatilization rate of CuCl2 with the increase of CaO/SiO2 is approximately U form. For Kinetics study the results show that: The two reactions can be described by 1-order kinetic model and 1/2-order kinetic modelin Nitrogen atmosphere, while 2/3-order and zero-order in Air atmosphere; The reaction order and activation energy all reduced with the increase of CaO/SiO2.