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

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°C/min, 15°C/min and 20°C/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.