Thermal kinetics and thermodynamics of the dehydration reaction of Mg3(PO4)2·22H2O

Authors : Fatma Tuğçe ŞENBERBER, Emek MÖRÖYDOR DERUN

Pages : 47-51

View : 19 | Download : 8

Publication Date : 2019-12-06

Article Type : Research Paper

Abstract :Mg 3 insert ignore into journalissuearticles values(PO 4 ); 2 ·22H 2 O lost its crystal water in the temperature range of 40 - 200°C and the calcined sample was identified as Mg 3 insert ignore into journalissuearticles values(PO 4 ); 2 , was a notable for its further treatments in optical and electrical applications. Dehydration process was studied using non-isothermal thermogravimetry insert ignore into journalissuearticles values(TG); applying model-fitting method. Different mechanism models insert ignore into journalissuearticles values(chemical reaction order, diffusion and phase interfacial reaction); were applied. The activation energies calculated for the dehydration reaction; and average of activation energy was found as 160 kJ/mol.  The better kinetic model of the dehydration reaction for Mg 3 insert ignore into journalissuearticles values(PO 4 ); 2 ·22H 2 O was selected as F3 insert ignore into journalissuearticles values(chemical reaction - third order);. The thermodynamic functions insert ignore into journalissuearticles values(ΔH, ΔG and ΔS); of the dehydration reaction were calculated by the activated complex theory and found that the process was endothermic, non-spontaneous and fast.
Keywords : Magnesium phosphate, decomposition kinetic, thermal behaviour, thermodynamic