Thermoanalytical studies of silver and lead jarosites and their solid solutions |
| |
| Authors: | Ray L Frost Sara J Palmer János Kristóf Erzsébet Horváth |
| |
| Institution: | 1.Inorganic Materials Research Program, School of Physical and Chemical Sciences,Queensland University of Technology,Brisbane,Australia;2.Department of Analytical Chemistry,University of Pannonia,Veszprém,Hungary;3.Department of Environmental Engineering and Chemical Technology,University of Pannonia,Veszprém,Hungary |
| |
| Abstract: | Dynamic and controlled rate thermal analysis has been used to characterise synthesised jarosites of formula M(Fe)3(SO4)2(OH)6] where M is Pb, Ag or Pb–Ag mixtures. Thermal decomposition occurs in a series of steps. (a) dehydration, (b) well defined
dehydroxylation and (c) desulphation. CRTA offers a better resolution and a more detailed interpretation of water formation
processes via approaching equilibrium conditions of decomposition through the elimination of the slow transfer of heat to
the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes of water formation
reveal the subtle nature of dehydration and dehydroxylation. CRTA offers a better resolution and a more detailed interpretation
of the decomposition processes via approaching equilibrium conditions of decomposition through the elimination of the slow
transfer of heat to the sample as a controlling parameter on the process of decomposition. Constant-rate decomposition processes
of non-isothermal nature reveal separation of the dehydroxylation steps, since in these cases a higher energy (higher temperature)
is needed to drive out gaseous decomposition products through a decreasing space at a constant, pre-set rate. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
