Journal of Thermal Analysis and Calorimetry

, Volume 135, Issue 3, pp 1891–1898 | Cite as

The aid of calorimetry for kinetic and thermal study

Application to the dissolution of Tunisian natural phosphates
  • Balsam Belgacem
  • Sébastien LeveneurEmail author
  • Mohamed Chlendi
  • Lionel Estel
  • Mohamed Bagane


Phosphoric acid, a non-renewable chemical, is used in different industries. Production of this chemical from natural phosphate can be done by two routes: wet process and thermal process. The nature of the natural phosphate, i.e., its chemical composition, plays an important role in the kinetics and thermodynamics of phosphoric acid production. Thus, the establishment of a kinetic model, based on reaction mechanism, for the dissolution of natural phosphate is cumbersome due to the presence of impurities. Besides, one should use an online analytical method because the dissolution reaction is fast. The dissolution of two natural phosphates with different percentages of phosphorus pentoxide (P2O5), phosphate samples (28 mass% of P2O5) from Gafsa region (Tunisia) and phosphate samples (18 mass% of P2O5) from Cheketma-Kasserine region (Tunisia), was studied from a kinetic and thermal aspect. Experiments were performed by using a Tian—Calvet calorimeter. Two acid solutions were used for the dissolution: one with phosphoric acid (S1) and the other a mixture of phosphoric and sulfuric acid (S2). For both natural phosphates, it was found that in case of using S1 solution the heat released due to the dissolution was lower than in case of using solution S2. This difference was explained by the precipitation of monohydrate sulfate calcium to its dihydrate form. By using a granulometry distribution lower than 500 μm, heat released during the dissolution of both phosphates by S1 was similar, i.e., − 230 J g−1, and the same observation was done by using S2 solution, i.e., between − 300 and − 350 J g−1. We have demonstrated that granulometry distribution plays an important role, and by using a granulometry lower than 120 μm for Cheketma-Kasserine region phosphate, the heat released during the dissolution was higher, i.e., − 400 J g−1 with solution S2. Avrami model was found to describe the precipitation of calcium sulfate, and three distinguished domains were obtained by using Gafsa region phosphate compared to two domains with Cheketma-Kasserine region phosphate.


Tian—Calvet calorimeter Natural phosphate Dissolution Thermodynamics Kinetics Avrami equation 



The authors gratefully acknowledge the support of this work by the Research Unit of Applied Thermodynamics at the National School of Engineers of Gabes and the Laboratoire de Sécurité des Procédés Chimiques (LSPC) at INSA Rouen.


  1. 1.
    Mohammadkhani M, Noaparast M, Shafaei SZ, Amini A, Amini E, Abdollahi H. Double reverse flotation of a very low grade sedimentary phosphate rock, rich in carbonate and silicate. Int J Miner Process. 2011;100:157–65.CrossRefGoogle Scholar
  2. 2.
    Gharabaghi M, Noaparast M, Irannajad M. Selective leaching kinetics of low-grade calcareous phosphate ore in acetic acid. Hydrometallurgy. 2009;95:341–5.CrossRefGoogle Scholar
  3. 3.
    Amorri, Z. Réduction de la teneur en matière organique contenue dans l’acide phosphorique de voie humide par le peroxyde d’hydrogène et l’argile naturelle. PhD dissertation, National Engineering School of Gabes, Tunisia; 2012.Google Scholar
  4. 4.
    Pereira, F. Production d’acide phosphorique par attaque chlorhydrique de minerais phosphatés avec réductions des nuisances environnementales et récupération des terres rares entant que sous-produits. PhD dissertation, Ecole Nationale Supérieure des Mines de Saint-Etienne, France; 2003.Google Scholar
  5. 5.
    Sikdar SK, Ore F, Moore JH. Crystallisation of calcium sulfate hemihydrate in reagent-grade phosphoric acid. AIChE Symp Ser. 1980;76(193):82–9.Google Scholar
  6. 6.
    Antar K, Brahim K, Jemal M. Étude cinétique et thermodynamique de l’attaque d’une fluorapatite par des mélanges d’acides sulfurique et phosphorique À 25° C. Thermochim Acta. 2006;449:35–41.CrossRefGoogle Scholar
  7. 7.
    Brahim K, Khattech I, Dubès JP, Jemal M. Etude cinétique et thermodynamique de la dissolution de la fluorapatite dans l’acide phosphorique. Thermochim Acta. 2005;436:43–50.CrossRefGoogle Scholar
  8. 8.
    Van der Sluis S, Meszaros Y, Marchee WGJ, Wesselingh HA, Van Rosmalen GM. The digestion of phosphate ore in phosphoric acid. Ind Eng Chem Res. 1987;26:2501–5.CrossRefGoogle Scholar
  9. 9.
    Brahim K, Antar K, Khattech I, Jemal M. Effect of temperature on the attack of fluorapatite by a phosphoric acid solution. Sci Res Essays. 2008;3(1):35–9.Google Scholar
  10. 10.
    Antar K, Jemal M. Kinetics and thermodynamics of the attack of a phosphate ore by acid solutions at different temperatures. Thermochim Acta. 2008;474:32–5.CrossRefGoogle Scholar
  11. 11.
    Vaimakis TC, Economou ED, Trapalis CC. Calorimetric study of dissolution kinetics of phosphorite in diluted acetic acid. J Therm Anal Calorim. 2008;92:783–9.CrossRefGoogle Scholar
  12. 12.
    Soussi-Baatout A, Hichri M, Bechrifa A, Khattech I. Test and calibration processes for the differential reaction calorimeter (DRC): application: dissolution of calcium fluorapatite in the hydrochloric acid. Thermochim Acta. 2014;580:85–92.CrossRefGoogle Scholar
  13. 13.
    Zheng JL, Wärnå J, Salmi T, Burel F, Taouk B, Leveneur S. Kinetic modeling strategy for an exothermic multiphase reactor system: application to vegetable oils epoxidation using Prileschajew method. AIChE J. 2016;62:726–41.CrossRefGoogle Scholar
  14. 14.
    Rakotondramaro H, Wärnå J, Estel L, Salmi T, Leveneur S. Cooling and stirring failure for semi-batch reactor: application to exothermic reactions in multiphase reactor. J Loss Prev Process Ind. 2016;43:147–57.CrossRefGoogle Scholar
  15. 15.
    Avrami M. Granulation, phase change, and microstructure kinetics of phase change. III. J Chem Phys. 1941;9:177–84.CrossRefGoogle Scholar
  16. 16.
    Okur H, Tekin T, Ozer AK, Bayramoglu M. Effect of ultrasound on the dissolution of colemanite in H2SO4. Hydrometallurgy. 2002;67:79–86.CrossRefGoogle Scholar
  17. 17.
    Sevim F, Saraç H, Kocakerim MM, Yartaşı A. Dissolution kinetics of phosphate ore in H2SO4 solutions. Ind Eng Chem Res. 2003;42:2052–7.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2018

Authors and Affiliations

  • Balsam Belgacem
    • 1
  • Sébastien Leveneur
    • 2
    • 3
    Email author
  • Mohamed Chlendi
    • 1
  • Lionel Estel
    • 2
  • Mohamed Bagane
    • 1
  1. 1.Chemical Engineering Department, National Engineering School of Gabes (ENIG)University of GabesGabèsTunisia
  2. 2.INSA Rouen, UNIROUEN, LSPCNormandie UniversitéRouenFrance
  3. 3.Laboratory of Industrial Chemistry and Reaction Engineering, Process Chemistry CentreÅbo Akademi UniversityÅbo/TurkuFinland

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