Generic placeholder image

Current Physical Chemistry

Editor-in-Chief

ISSN (Print): 1877-9468
ISSN (Online): 1877-9476

Research Article

Effect of Co-precursor Maliec Anhydride on the Thermal Decomposition of Acetyl Ferrocene: A Reaction Kinetic Analysis

Author(s): Bratati Das and Ashis Bhattacharjee*

Volume 9, Issue 1, 2019

Page: [22 - 35] Pages: 14

DOI: 10.2174/1877946809666190201142153

Abstract

Background: Thermal decomposition of iron-bearing organometallic complex acetyl ferrocene, (C5H4COCH3)Fe(C5H5), leads to hematite (α-Fe2O3) nanoparticles. Presence of maliec anhydride, C4H2O3 as co-precursor during thermal decomposition modifies the size of the particles as well as the quantity of the reaction product significantly.

Objective: Kinetic analysis of the solid-state thermal reaction of acetyl ferrocene in the presence of varying amount of co-precursor maliec anhydride under inert reaction atmosphere has been studied in order to understand the reaction mechanism involved behind the formation of hematite and the role of co-precursor in the reaction process. For this purpose, reaction kinetic analysis of three mixtures of acetyl ferrocene and maliec anhydride has been carried out.

Methods: Thermogravimetry under non-isothermal protocol with multiple heating rates has been employed. The data are analyzed using model-free iso-conversional kinetic techniques to estimate the activation energy of reaction and reaction rate. The most-probable reaction mechanism has been identified by master plot method. The kinetic triplets (activation energy, reaction rate, most probable reaction mechanism function) have been employed to estimate the thermodynamic triplets (ΔS, ΔH and ΔG).

Observations: Acetyl Ferrocene (AFc) undergoes thermal decomposition in a four-step process leaving certain residual mass whereas maliec anhydride (MA) undergoes complete mass loss owing to melting followed by evaporation. In contrast, the (AFc1-x-MAx) mixtures undergo thermal decomposition through a two-step process, and the decompositions are completed at much lower temperatures than that in AFc. The estimated activation energy and reaction rate values are found strongly dependent on the extent of conversion as well as on the extent of mixing. Introduction of MA in the solid reaction atmosphere of AFc in one hand reduces the activation energy required by AFc to undergo thermal decomposition and the reaction rate, while on the other hand varies the nature of reaction mechanism involved.

Result: The range of reaction rate values estimated for the mixtures indicate that the activated complexes during Step-I of thermal decomposition may be treated as ‘loose’ complex whereas ‘tight’ complex for the Step-II. From the estimated entropy values, thermal process of (AFc1-x-MAx) mixture for Steps I and II may be interpreted as ‘‘slow’’ stage.

Conclusion: Variation of Gibb’s free energy with the fraction of maliec anhydride in the mixtures for Step-I and II indicate that the thermal processes of changing the corresponding activated complexes are non-spontaneous at room temperature.

Keywords: Acetyl ferrocene, maliec anhydride, model free method, non-isothermal thermogravimetry, reaction kinetics, thermal decomposition.

Graphical Abstract
[1]
Amara, D.; Grinblat, J.; Marge, S. Solventless thermal decomposition of ferrocene as a new approach for one-step synthesis of magnetite nanocubes and nanospheres. J. Mater. Chem., 2012, 22, 2188-2195.
[2]
Bhattacharjee, A.; Rooj, A.; Roy, M.; Kusz, J.; Gütlich, P. Solventless synthesis of hematite nanoparticles using ferrocene. J. Mater. Sci., 2013, 48, 2961-2968.
[3]
Perez De Berti, I.O.; Cagnoli, M.V.; Pecchi, G.; Alessandrini, J.L.; Stewart, S.J.; Bengoa, J.F.; Marchetti, S.G. Alternative low-cost approach to the synthesis of magnetic iron oxide nanoparticles by thermal decomposition of organic precursors. Nanotechnology, 2013, 24, 175601-175611.
[4]
Monteiro, S.D.; Da Souza, G.M.O. Thermal decomposition of precursors and iron oxide properties: influence of promoters (Mn and Cu) and preparation method. J. Therm. Anal. Calorim., 2016, 123, 955-963.
[5]
Das, B.; Kusz, J.; Reddy, V.R.; Zubko, M.; Bhattacharjee, A. Solventless synthesis, morphology, structure and magnetic properties of iron oxide nanoparticles. Solid State Sci., 2017, 74, 62-69.
[6]
Das, B.; Bhattacharjee, A. Kinetic analysis of nonisothermal decomposition of acetyl ferrocene. Int. J. Chem. Kinet., 2018, 51(1), 74-80.
[7]
Vlaev, L.; Nedelchev, N.; Gyurova, K.; Zagorcheva, M. A comparative study of non-isothermal kinetics of decomposition of calcium oxalate monohydrate. J. Anal. Appl. Pyrolysis, 2008, 81, 253-262.
[8]
Jankovi’c, B. Kinetic analysis of the nonisothermal decomposition of potassium metabisulfite using the model-fitting and isoconversional (model-free) methods. Chem. Eng. J., 2008, 139, 128-135.
[9]
Vyazovkin, S. The handbook of thermal analysis & calorimetry, in recent advances, techniques and applications.1st Ed.; Brown, M.E.; Gallagher, P.K.; Eds.; Elsevier: Amsterdam, The Netherlands; , 2008, Vol. 5,, pp. 1-691.
[10]
Farjas, J.; Roura, P. Modification of the Kolmogorov-Johnson-Mehl-Avrami rate equation for non-isothermal experiments and its analytical solution. Acta Mater., 2006, 54, 5573-5579.
[11]
Ozawa, T. A new method of analyzing thermogravimetric data. Bull. Chem. Soc. Jpn., 1965, 38, 1881-1886.
[12]
Flynn, J.H.; Wall, L.A. A quick, direct method for the determination of activation energy from thermogravimetric data. Polym. Lett., 1966, 4, 323-328.
[13]
Kissinger, H.E. Reaction kinetics in differential thermal analysis. Anal. Chem., 1957, 29, 1702-1706.
[14]
Akahira, T.; Sunose, T. Method of determining activation deterioration constant of electrical insulating materials. Res. Rep. Chiba. Instrum. Technol., 1971, 16, 22-31.
[15]
Starink, M.J. The determination of activation energy from linear heating rate experiments: a comparison of the accuracy of isoconversion methods. Thermochim. Acta, 2003, 404, 163-176.
[16]
Gao, Z.; Nakada, M.; Amasaki, I. A consideration of errors and accuracy in the isoconversional methods. Thermochim. Acta, 2001, 369, 137-142.
[17]
Vyazovkin, S. Modification of the integral isoconversional method to account for variation in the activation energy. J. Comput. Chem., 2001, 22, 178-183.
[18]
Vyazovkin, S. Model-free kinetics staying free of multiplying entities without necessity. J. Therm. Anal. Calorim., 2006, 83, 45-51.
[19]
Liavitskaya, T.; Vyazovkin, S. Delving into the kinetics of reversible thermal decomposition of solids measured on heating and cooling. J. Phys. Chem. C, 2017, 121(28), 15392-15401.
[20]
Cai, J.; Yao, F.; Yi, W.; He, F. New temperature integral approximation for nonisothermal kinetics. AIChE J., 2006, 52, 1554-1557.
[21]
M’alek, J. The kinetic analysis of non-isothermal data. Thermochim. Acta, 1992, 200, 257-269.
[22]
Gotor, F.J.; Criado, J.M.; M’alek, J.; Koga, M. Kinetic analysis of solid-state reactions: the universality of master plots for analyzing isothermal and nonisothermal experiments. J. Phys. Chem. A, 2000, 104, 10777-10782.
[23]
Young, D. Decomposition of solids, 1st ed; Pergamon Press: Oxford, 1966, p. 209.
[24]
Cordes, H.M. Pre-exponential factors for solid-state thermal decomposition. J. Phys. Chem., 1968, 72, 2185-2189.
[25]
Das, B.; Bhattacharjee, A. Study on the melting mechanism of maleic anhydride. Communicated.,
[26]
Yang, H.C.; Eun, H.C.; Cho, Y.Z.; Kim, E.H.; Kim, I.T. Kinetic study of a thermal dechlorination and oxidation of neodymium oxychloride. Thermochim. Acta, 2007, 460, 53-59.
[27]
Vyazovkin, S.; Wight, C.A. Model-free and model-fitting approaches to kinetic analysis of isothermal and nonisothermal data. Thermochim. Acta, 1999, 340-341, 53-68.
[28]
Wanjun, T.; Donghua, C.; Cunxin, W. Kinetic study on the thermal dehydration of CaCO3·H2O by the master plots method. AIChE J., 2006, 52, 2211-2216.

© 2024 Bentham Science Publishers | Privacy Policy