Login for students

Login for employees

Publication detail

Thermal decomposition of mixed calcium oxalate hydrates - kinetic deconvolution of complex heterogeneous processes
Authors: Svoboda Roman | Olmrová Zmrhalová Zuzana | Galusek Dusan | Brandová Daniela | Chovanec Jozef
Year: 2020
Type of publication: článek v odborném periodiku
Name of source: Physical Chemistry Chemical Physics
Publisher name: Royal Society of Chemistry
Place: Cambridge
Page from-to: 8889-8901
Titles:
Language Name Abstract Keywords
cze Tepelný rozklad směsných hydrátů šťavelanu vápenatého - kinetická dekonvoluce heterogenních procesů Dehydratace a následný rozklad hydrátů šťavelanu vápenatého byly studovány pomocí DSC, TG a in situ XRD. Výsledky byly zpracovány za účelem dekonvoluce probíhajících procesů a stanovení kinetiky jednotlivých dějů. štavelan vápenatý; hydrát; dehydratace; rozklad; DSC; TG; in situ XRD; kinetika; dekonvoluce
eng Thermal decomposition of mixed calcium oxalate hydrates - kinetic deconvolution of complex heterogeneous processes Differential scanning calorimetry (DSC), thermogravimetry (TG) and in situ XRD were used to study dehydration and consequent decomposition reactions of mixed calcium oxalate hydrates. As the complex dehydration kinetics exhibited certain trends with respect to the applied heating rate, the modified multivariate kinetic analysis approach (based on averaged curve-by-curve optimizations) was employed to obtain a full kinetic description of the data. The Sestak-Berggren equation was used to model the two consequent dehydration reactions. Good agreement was found between the kinetic parameters calculated from the DSC and TG data - approximate values of activation energies were 68 and 81 kJ mol(-1) for the trihydrate -> monohydrate and monohydrate -> anhydride transformations, respectively. A procedural methodology was developed to predict both dehydration kinetics and hydrate content ratios. For the calcium oxalate decomposition the TG technique provided very precise single-step prediction with an activation energy of 180 kJ mol(-1). DSC on the other hand provided complex information on joint decomposition and carbon monoxide oxidation reactions - the proposed reaction mechanism includes completion of two reaction paths composed of consequent chemical reactions. A mechanistic view of the complex reaction path is discussed in terms of the diffusion barrier limiting the oxidation step. urinary calculi; crystal-growth; kidney-stones; activation-energy; phase-change; dehydration; whewellite; crystallization; raman; precipitation

Departments

Other Parts

Map

en.mapy.cz

Services

Popular Links

© 2023 University of Pardubice, Studentská 95, 532 10 Pardubice 2
Phone: +420 466 036 111, 466 036 112, 466 036 113
Webmaster, RSS
Data box ID: f5vj9hu
Accessibility Statement
CC BY-NC-ND 4.0