Materiales de Construcción, Vol 64, No 316 (2014)

Effect of citric acid and the hemihydrate amount on the properties of a calcium sulphoaluminate cement

G. Velazco
Cinvestav Saltillo, Mexico

J. M. Almanza
Cinvestav Saltillo, Mexico

D. A. Cortés
Cinvestav Saltillo, Mexico

J. C. Escobedo
Cinvestav Saltillo, Mexico

J. I. Escalante-Garcia
Cinvestav Saltillo, Mexico


The influence of citric acid on the hydration and strength development of a calcium sulphoaluminate cement was investigated. Cement pastes were prepared by mixing calcium sulphoaluminate (C4A3Ŝ) with 15, 20 and 25wt% of hemihydrate (CŜH0.5). Citric acid was added as a retarder at 0 and 0.5wt%. The samples were cured at 20 °C for periods of time from 1 to 28 days to evaluate their compressive strength and to characterize the hydration products by scanning electron microscopy and X-ray diffraction. Calorimetric curves showed that the retarding agent considerably decreases the heat release rate and the quantity of total heat released. The main product after the curing was ettringite (C63H32). The morphology of this phase consisted of long and thin needles growing radially on the cement grains. Samples with 15wt% of hemihydrate and 0.5wt% of citric acid developed the highest compressive strength (70 MPa) at 28 days of curing.


Calorimetry; Ettringite; Sulphoaluminate; Citric acid

Full Text:



1. Sharp, J.H.; Lawrence, C.D.; Yang, R. (1999) Calcium sulphoaluminate cements – low-energy cements, special cements or what? Adv. Cem. Res., 11 [1], 3–13.

2. Propescu, C.D.; Mountean, M.; Sharp, J.H. (2003) Industrial trial production of low energy belite cement. Cem. Concr. Comp., 25 [7], 689–693.

3. Juenger, M.C.G.; Winnefeld, F.; Provis, J.L.; Ideker, J.H. (2011) Advances in alternative cementitious binders. Cem. Concr. Res., 41 [12], 1232–1243.

4. Gartner, E. (2004) Industrially interesting approaches to ''low-CO2'' cements. Cem. Concr. Res., Vol. 34 [9], 1491–1496.

5. Odler, I. (2000) Special inorganic cements, Ed. Library Binding, Great Britain.

6. Kasselouri, V.; Tsakiridis, P.; Malami, Ch.; Georgali, B.; Alexandridou, C. (1995) A study on the hydration products of non-expansive calcium sulfoaluminate cement. Cem. Concr. Res., 25 [8], 1726–1736.

7. Metha, P.K.; Klein, A. (1965) Formation of Ettringite by Hydration of a System Containing an Anhydrous Calcium Sulfoaluminate. J. Am. Cer. Soc., 48 [8], 435–436.

8. Puertas, F.; Blanco, M.T.; Gimenez-Molina, S. (1995) Kinetics of the thermal decomposition of C4A3S^ in air. Cem. Concr. Res., 25 [3], 572–580.

9. Glasser, F.P.; Zhang, L. (2001) High-performance cement matrices based on calcium sulfoaluminate–belite compositions. Cem. Concr. Res., 31 [12], 1881–1886.

10. Arjunan, P.; Silsbee, M.R.; Roy, D.M. (1999) Sulfoaluminate-belite cement from low-calcium fly ash and sulfur rich and other industrial by-products. Cem. Concr. Res., 29 [8], 1305–1309.

11. Perá, J.; Ambroise, J. (2004) New applications of calcium sulfoaluminate cement. Cem. Concr. Res., Vol. 34 [4], 671–676.

12. Sahu, S.; Havlica, J.; Tomková, V.; Majling, J. (1991) Hydration behaviour of sulphoaluminate belite cement in the presence of various calcium sulphates. Thermochimica Acta, 175 [1], 45–52.

13. Winnefeld, F.; Lothenbach, B. (2010) Hydration of calcium sulphoaluminate cements - experimental findings and thermodinamic modeling. Cem. Concr. Res., 40 [1], 1239–1247.

14. Escalante-Garcia, J.I.; Rios-Escobar, M.; Gorokhovsky, A.; Fuentes, A.F. (2008) Fluorgypsum binders with OPC and PFA additions, strength and reactivity as a function of component proportioning and temperatura, Cem. Concr. Comp., 30 [2] 88–96.

15. Lorprayon, V.; Rossington, D.R. (1981) Early hydration of cement constituents with organic admixtures. Cem. Concr. Res., 11 [2], 267–277.

16. Hewlett, P.C. (2004) Lea's Chemistry of Cement and Concrete 4th Edition, Elsevier, (2004).

17. Tinnea, J.; Young, J.F. (1977) Influence of citric acid on reactions in the system 3CaO-Al2O3-CaSO4·H2O-CaO-H2O. J. Am. Ceram. Soc., 60 [9], 387–389.

18. Singh, N.B.; Shing, A.K.; Shing, S.P. (1990) Hydration study of the system Ca3Al2O6-CaSO4·2H2O-Ca(OH)2-H2O with and without citric acid. J. Am. Ceram. Soc., 73 [10], 3063–3068.

19. Möschner, G.; Lothenbach, B.; Figi, R.; Kretschmar, R. (2009) Influence of citric acid on the hydration of Portland cement. Cem. Concr. Res., 39 [4], 275–282.

20. ASTM C-204, Fineness of Hydraulic Cement by Air Permeability Apparatus, 1995 Annual Book of ASTM Standars. Section 4. Construction. Volume 04.01. Cement, Lime, Gypsum.

21. Ramachandran, V.R.; Beaudoin, J.J. (2001) Handbook of Analytical Techniques in Concrete Science and Technologies. Noyes Publications, (2001).

22. Kurdowsky, W.; Nokun-Wzcelik, W. (1995) Calorimetric Studies Of Special Cements. J. Therm. Anal., 45 [10], 923–930.

23. Escalante, J.I.; Sharp, J.H. (2000) The effect of temperature on early hydration of Portland cement and blended cements. Adv. Cem. Res., 12 [3], 121–130.

24. Winnefeld, F.; Barlag, S. (2010) Calorimetric and thermogavimetric study on the influence of calcium sulfate on the hydration of ye'elimite. J. Therm. Anal. Calorim., 101 [3], 949–957.

25. Magallanes-Rivera, R.X.; Escalante-Garcia, J.I.; Gorokhovsky, A. (2009) Hydration reactions and microstructural characteristics of hemihydrate with citric and malic acid, Constr Build Mater, 23 [3] 1298–1305.

26. Quennoz, A.; Scrivener, K.L. (2012) Hydration of C3A–gypsum systems. Cem. Concr. Res., 42 [7], 1032–1041.

27. Motzet, H.; Pöllmann, H. (1999) Synthesis and characterisation of sulfite-containing AFm phases in the system CaO-Al2O3-SO2-H2O. Cem. Concr. Res., 29 [7], 1005–1011.

Copyright (c) 2014 Consejo Superior de Investigaciones Científicas (CSIC)

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.

Contact us

Technical support