화학공학소재연구정보센터
Indian Journal of Chemical Technology, Vol.5, No.1, 35-40, 1998
Non-isothermal kinetics of solid-state decomposition
Study of transport phenomena across gas-solid interface requires accurate knowledge of single particle kinetics. In our laboratory a quadrupole mass spectrometer (QMS) based evolved gas analysis (EGA-MS) system has been set up to investigate the kinetics of temperature programmed decomposition (TPD) of inorganic solids from mass spectral gas release data. Using this facility a number of inorganic solids have been studied for their decomposition behaviour. Fractional reaction parameter alpha obtained from release profiles has been used to derive functional conversional transform f(alpha) of various nonisothermal kinetic rate expressions based on random nucleation, diffusion and interface motion. The corresponding integral model function g(alpha) was used to fit experimental data to theoretical plots. The best fits pertain to the kinetic control regime prevalent over the particular decomposition stage. From In[g(alpha)/T-2] vs 1/T curves, arrhenius parameters like activation energy and pre-exponential factor have been calculated. In this paper, a brief description of the experimental facility and results on thermal decomposition of CuSO4.5H(2)O, AlNH4(SO4)(2).12H(2)O and Th(NO3)(4).5H(2)O are presented.