Computers and Concrete

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Investigation of physicochemical properties, sustainability and environmental evaluation of metakaolin- granulated blast furnace slag geopolymer concrete

  • Anas Driouich (Laboratory of Process Engineering and Environment, Faculty of Sciences and Technology, University Hassan II) ;
  • Safae El Alami El Hassani (Laboratory of Process Engineering and Environment, Faculty of Sciences and Technology, University Hassan II) ;
  • Zakia Zmirli (Laboratory of Advanced Materials and Process Engineering, Faculty of Sciences, University Ibn Tofail) ;
  • Slimane El Harfaoui (Laboratory of Process Engineering and Environment, Faculty of Sciences and Technology, University Hassan II) ;
  • Nadhim Hamah Sor (Civil Engineering Department, University of Garmian) ;
  • Ayoub Aziz (Geo-Biodiversity and Natural Patrimony Laboratory (GEOBIO), Scientific Institute, "Geophysics, Natural Patrimony and Green Chemistry" Research Center (GEOPAC), Mohammed V University in Rabat) ;
  • Jong Wan Hu (Department of Civil and Environmental Engineering, Incheon National University) ;
  • Haytham F. Isleem (Department of Construction Management, Qujing Normal University) ;
  • Hadee Mohammed Najm (Department of Civil Engineering, Zakir Husain Engineering College, Aligarh Muslim University) ;
  • Hassan Chaair (Laboratory of Process Engineering and Environment, Faculty of Sciences and Technology, University Hassan II)
  • Received : 2023.03.18
  • Accepted : 2024.03.18
  • Published : 2024.10.25
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Abstract

Geopolymers are part of a class of materials characterized by properties combining polymers, ceramics, and cement. These include exceptionally high thermal and chemical stability, excellent mechanical strength and durability in aggressive environments. This work deals with the synthesis, characterization, and sustainability evaluation of GPGBFS-MK geopolymers by alkaline activation of a granulated blast furnace slag-metakaolin mixture. In the first step, elemental and oxide analyses by XRF and EDS showed that the main constituents of GPGBFS-MK geopolymers are silicon, sodium, and aluminium oxides. The structural analyses by XRD and FTIR confirmed that the geopolymerization for GPGBFS-MK geopolymers did occur, accompanied by the formation of disordered networks from the blends and a modification to the microstructure by the geopolymerization process. Similarly, the microstructural study made by SEM showed that the GPGBFS-MK geopolymers are constituted by aluminosilicates in the form of dense clusters on which are adsorbed particles of unreacted GBFS in the form of spheroids and white residues of the alkaline activating solution. In addition, the study of the sustainability evaluation of GPGBFS-MK geopolymers showed that the water absorption of geopolymeric materials is lower than that of OPC cement. As for the elevated temperature resistance, the analyses indicated an excellent elevated temperature resistance of GPGBFS-MK. In the same way, the study of the resistance to chemical aggressions showed that the GPGBFS-MK geopolymeric materials are unattackable, contrary to the OPC cement-based materials which are strongly altered.

Keywords

Acknowledgement

This research is supported by the Ministry of Trade, Industry and Energy and the Institute for Industrial Technology Evaluation and Management (KEIT) in 2022. (Project No.: RS-2022-00154935, Title: Manufacturing of non-carbonate raw materials and development of cement technology to replace limestone with 5 wt.% or more).

References

  1. Aadi, A.S., Sor, N.H. and Mohammed, A.A. (2021), "The behavior of eco-friendly self-compacting concrete partially utilized ultra-fine eggshell powder waste", J. Phys.: Conf. Ser., 1973(1), 012143. https://doi.org/10.1088/1742-6596/1973/1/012143.
  2. Abed, J.M., Khaleel, B.A., Aldabagh, I.S. and Sor, N.H. (2021), "The effect of recycled plastic waste polyethylene terephthalate (PET) on characteristics of cement mortar", J. Phys.: Conf. Ser., 1973(1), 012121. https://doi.org/10.1088/1742-6596/1973/1/012121
  3. Ahmed, H.U., Mahmood, L.J., Muhammad, M.A., Faraj, R.H., Qaidi, S.M., Sor, N.H., ... and Mohammed, A.A. (2022b), "Geopolymer concrete as a cleaner construction material: An overview on materials and structural performances", Clean. Mater., 5, 100111. https://doi.org/10.1016/j.clema.2022.100111.
  4. Ahmed, H.U., Mohammed, A.A., Rafiq, S., Mohammed, A.S., Mosavi, A., Sor, N.H. and Qaidi, S. (2021), "Compressive strength of sustainable geopolymer concrete composites: A state-of-the-art review", Sustainab., 13(24), 13502. https://doi.org/10.3390/su132413502.
  5. Ahmed, H.U., Mohammed, A.S., Faraj, R.H., Abdalla, A.A., Qaidi, S., Sor, N.H. and Mohammed, A.A. (2023), "Innovative modeling techniques including MEP, ANN and FQ to forecast the compressive strength of geopolymer concrete modified with nanoparticles", Neural Comput. Appl., 35(17), 12453-12479. https://doi.org/10.1007/s00521-023-08378-3.
  6. Ahmed, H.U., Mohammed, A.S., Qaidi, S.M., Faraj, R.H., Hamah Sor, N. and Mohammed, A.A. (2022a), "Compressive strength of geopolymer concrete composites: A systematic comprehensive review, analysis and modeling", Eur. J. Environ. Civil Eng., 27(3), 1383-1428. https://doi.org/10.1080/19648189.2022.2083022.
  7. Ahmed, S.N., Sor, N.H., Ahmed, M.A. and Qaidi, S.M. (2022c), "Thermal conductivity and hardened behavior of eco-friendly concrete incorporating waste polypropylene as fine aggregate", Mater. Today: Proc., 57, 818-823. https://doi.org/10.1016/j.matpr.2022.02.417.
  8. Akcaoglu, T., Cubukcuoglu, B. and Awad, A. (2019), "A critical review of slag and fly-ash based geopolymer concrete", Comput. Concrete, 24(5), 453-458. https://doi.org/10.12989/cac.2019.24.5.453.
  9. Akcaozoglu, S. and Ulu, C. (2014), "Recycling of waste PET granules as aggregate in alkali-activated blast furnace slag/metakaolin blends", Constr. Build. Mater., 58, 31-37. https://doi.org/10.1016/j.conbuildmat.2014.02.011.
  10. Aldabagh, I.S., Abed, J.M., Khaleel, B.A. and Sor, N.H. (2022), "Influence of water quality and slag on the development of mechanical properties of self compacting mortar", Mater. Today: Proc., 57, 892-897. https://doi.org/10.1016/j.matpr.2022.02.575.
  11. Althoey, F., Sor, N.H., Hadidi, H.M., Shah, S.F.A., Alaskar, A., Eldin, S.M., ... and Javed, M.F. (2023), "Crack width prediction of self-healing engineered cementitious composite using multi-expression programming", J. Mater. Res. Technol., 24, 918-927. https://doi.org/10.1016/j.jmrt.2023.03.036.
  12. Aziz, A. (2023), "Structural and Physico-mechanical investigations of new acidic geopolymers based on natural Moroccan pozzolan: A parametric study", Silicon, 15(3), 1133-1144. https://doi.org/10.1007/s12633-022-02089-5.
  13. Aziz, A., Bellil, A., El Hassani, I.E.E.A., Fekhaoui, M., Achab, M., Dahrouch, A. and Benzaouak, A. (2021), "Geopolymers based on natural perlite and kaolinic clay from Morocco: Synthesis, characterization, properties, and applications", Ceram. Int., 47(17), 24683-24692. https://doi.org/10.1016/j.ceramint.2021.05.190.
  14. Aziz, A., Driouich, A., Felaous, K. and Bellil, A. (2023), "Box-Behnken design based optimization and characterization of new eco-friendly building materials based on slag activated by diatomaceous earth", Constr. Build. Mater., 375, 131027. https://doi.org/10.1016/j.conbuildmat.2023.131027.
  15. Aziz, A., Felaous, K., Alomayri, T. and Jindal, B.B. (2023), "A state-of-the-art review of the structure and properties of laterite-based sustainable geopolymer cement", Environ. Sci. Pollut. Res., 30(19), 54333-54350. https://doi.org/10.1007/s11356-023-26495-3.
  16. Bellil, A., Aziz, A., El Amrani El Hassani, I.I., Achab, M., El Haddar, A. and Benzaouak, A. (2022), "Producing of lightweight concrete from two varieties of natural pozzolan from the Middle Atlas (Morocco): Economic, ecological, and social implications", Silicon, 14(8), 4237-4248. https://doi.org/10.1007/s12633-021-01155-8.
  17. Bernal, S.A., De Gutierrez, R.M. and Provis, J.L. (2012), "Engineering and durability properties of concretes based on alkali-activated granulated blast furnace slag/metakaolin blends", Constr. Build. Mater., 33, 99-108. https://doi.org/10.1016/j.conbuildmat.2012.01.017.
  18. Bheel, N., Ali, M.O.A., Liu, Y., Tafsirojjaman, T., Awoyera, P., Sor, N.H. and Bendezu Romero, L.M. (2021a), "Utilization of corn cob ash as fine aggregate and ground granulated blast furnace slag as cementitious material in concrete", Build., 11(9), 422. https://doi.org/10.3390/buildings11090422.
  19. Bheel, N., Awoyera, P., Tafsirojjaman, T. and Sor, N.H. (2021a), "Synergic effect of metakaolin and groundnut shell ash on the behavior of fly ash-based self-compacting geopolymer concrete", Constr. Build. Mater., 311, 125327. https://doi.org/10.1016/j.conbuildmat.2021.125327.
  20. Bohac, M., Palou, M., Novotny, R., Masilko, J., Vsiansky, D. and Stanek, T. (2014), "Investigation on early hydration of ternary Portland cement-blast-furnace slag-metakaolin blends", Constr. Build. Mater., 64, 333-341. https://doi.org/10.1016/j.conbuildmat.2014.04.018.
  21. Chen, Z., Wan, X., Qian, Y., Qiao, J., Jia, J., Mo, L., ... and Min, F. (2021), "The effect on the compressive strength of fly ash based geopolymer concrete with the generation of hydroxy sodalite", Constr. Build. Mater., 309, 125174. https://doi.org/10.1016/j.conbuildmat.2021.125174.
  22. Cheng, S., Shui, Z., Sun, T., Yu, R., Zhang, G. and Ding, S. (2017), "Effects of fly ash, blast furnace slag and metakaolin on mechanical properties and durability of coral sand concrete", Appl. Clay Sci., 141, 111-117. https://doi.org/10.1016/j.clay.2017.02.026.
  23. Cong, P. and Cheng, Y. (2021), "Advances in geopolymer materials: A comprehensive review", J. Traffic Transp. Eng., 8(3), 283-314. https://doi.org/10.1016/j.jtte.2021.03.004.
  24. Dadsetan, S. and Bai, J. (2017), "Mechanical and microstructural properties of self-compacting concrete blended with metakaolin, ground granulated blast-furnace slag and fly ash", Constr. Build. Mater., 146, 658-667. https://doi.org/10.1016/j.conbuildmat.2017.04.158.
  25. Davidovits, J. (1994), "Global warming impact on the cement and aggregates industries", World Resour. Rev., 6(2), 263-278.
  26. Driouich, A., Chajri, F., El Hassani, S., Britel, O., Belouafa, S., Khabbazi, A. and Chaair, H. (2020), "Optimization synthesis geopolymer based mixture metakaolin and fly ash activated by alkaline solution", J. Non-Cryst., 544, 120197. https://doi.org/10.1016/j.jnoncrysol.2020.120197.
  27. Driouich, A., Chajri, F., El Hassani, S., Britel, O., Digua, K. and Chaair, H. (2020), "Synthesis and characterization of silicate gel by using sol-gel process: Experiments and DFT calculations", Mediterr. J. Chem., 9(6), 411-421. http://dx.doi.org/10.13171/mjc9602001011134hc.
  28. Driouich, A., El Hassani, S., Labjar, H., Kassbi, S., Kambuyi, N., Britel, O., Sallek, B., Digua, K., Chroqui, R. and Chaair, H. (2020), "Modeling and optimizing synthesis of irreversible gel by sol-gel using experimental design", Phosphorus Sulfur Silicon Relat. Elem., 195(1), 50-59. https://doi.org/10.1080/10426507.2019.1634718.
  29. Dupuy, C., Havette, J., Gharzouni, A., Texier-Mandoki, N., Bourbon, X. and Rossignol, S. (2019), "Metakaolin-based geopolymer: Formation of new phases influencing the setting time with the use of additives", Constr. Build Mater., 200, 272-281. https://doi.org/10.1016/j.conbuildmat.2018.12.114.
  30. Duxson, P., Fernandez-Jimenez, A., Provis, J.L., Lukey, G.C., Palomo, A. and Van Deventer, J.S. (2007), "Geopolymer technology: The current state of the art", J. Mater. Sci., 42, 2917-2933. https://doi.org/10.1007/s10853-006-0637-z.
  31. Felaous, K., Aziz, A. and Achab, M. (2023), "Physico-mechanical and durability properties of new eco-material based on blast furnace slag activated by Moroccan diatomite gel", Environ. Sci. Pollut. Res., 30, 3549-3561. https://doi.org/10.1007/s11356-022-22461-7.
  32. Felaous, K., Aziz, A., Achab, M., Fernandez-Raga, M. and Benzaouak, A. (2023), "Optimizing alkaline activation of natural volcanic pozzolan for eco-friendly materials production: An investigation of NaOH molarity and Na2SiO3-to-NaOH ratio", Sustainab., 15(5), 4453. https://doi.org/10.3390/su15054453.
  33. Hamah Sor, N., Hilal, N., Faraj, R.H., Ahmed, H.U. and Sherwani, A.F.H. (2022), "Experimental and empirical evaluation of strength for sustainable lightweight self-compacting concrete by recycling high volume of industrial waste materials", Eur. J. Environ. Civil Eng., 26(15), 7443-7460. https://doi.org/10.1080/19648189.2021.1997827.
  34. Hilal, N., Hamah Sor, N. and Faraj, R.H. (2021), "Development of eco-efficient lightweight self-compacting concrete with high volume of recycled EPS waste materials", Environ. Sci. Pollut. Res., 28(36), 50028-50051. https://doi.org/10.1007/s11356-021-14213-w.
  35. Hilal, N., Tawfik, T.A., Ahmed, S.N. and Hamah Sor, N. (2022a), "The effect of waste medical radiology as fiber reinforcement on the behavior of eco-efficient self-compacting concrete", Environ. Sci. Pollut. Res., 29(32), 49253-49266. https://doi.org/10.1007/s11356-022-19360-2.
  36. Hilal, N., Tawfik, T.A., Edan, H.H. and Hamah Sor, N. (2022b), "The mechanical and durability behaviour of sustainable self-compacting concrete partially contained waste plastic as fine aggregate", Austr. J. Civil Eng., 21(2), 151-166. https://doi.org/10.1080/14488353.2022.2083408.
  37. Ismail, I., Bernal, S.A., Provis, J.L., San Nicolas, R., Hamdan, S. and van Deventer, J.S. (2014), "Modification of phase evolution in alkali-activated blast furnace slag by the incorporation of fly ash", Cement Concrete Compos., 45, 125-135. https://doi.org/10.1016/j.cemconcomp.2013.09.006.
  38. Jamil, N.H., Abdullah, M.M.A.B., Pa, F.C., Mohamad, H., Ibrahim, W.M.A.W. and Chaiprapa, J. (2020), "Influences of SiO2, Al2O3, CaO and MgO in phase transformation of sintered kaolin-ground granulated blast furnace slag geopolymer", J. Mater. Res. Technol., 9(6), 14922-14932. https://doi.org/10.1016/j.jmrt.2020.10.045.
  39. Jindal, B.B., Singhal, D., Sharma, S. and Parveen, J. (2018), "Enhancing mechanical and durability properties of geopolymer concrete with mineral admixture", Comput. Concrete, 21(3), 345-353. https://doi.org/10.12989/cac.2018.21.3.345.
  40. Kamath, M., Prashant, S. and Kumar, M. (2021), "Micro-characterisation of alkali activated paste with fly ash-GGBS-metakaolin binder system with ambient setting characteristics", Constr. Build. Mater., 277, 122323. https://doi.org/10.1016/j.conbuildmat.2021.122323.
  41. Kocak, Y. (2020), "Effects of metakaolin on the hydration development of Portland-composite cement", J. Build. Eng., 31, 101419. https://doi.org/10.1016/j.jobe.2020.101419.
  42. Kumar, P., Pankar, C., Manish, D. and Santhi, A.S. (2018), "Study of mechanical and microstructural properties of geopolymer concrete with GGBS and Metakaolin", Mater. Today: Proc., 5(14), 28127-28135. https://doi.org/10.1016/j.matpr.2018.10.054.
  43. Li, C., Sun, H. and Li, L. (2010), "A review: The comparison between alkali-activated slag (Si+ Ca) and metakaolin (Si+ Al) cements", Cement Concrete Res., 40(9), 1341-1349. https://doi.org/10.1016/j.cemconres.2010.03.020.
  44. Mansi, A., Sor, N.H., Hilal, N. and Qaidi, S.M. (2022), "The impact of nano clay on normal and high-performance concrete characteristics: A review", IOP Conf. Ser.: Earth Environ. Sci., 961(1), 012085. https://doi.org/10.1088/1755-1315/961/1/012085.
  45. Mehdipour, S., Nikbin, I.M., Dezhampanah, S., Mohebbi, R., Moghadam, H., Charkhtab, S. and Moradi, A. (2020), "Mechanical properties, durability and environmental evaluation of rubberized concrete incorporating steel fiber and metakaolin at elevated temperatures", J. Clean. Prod., 254, 120126. https://doi.org/10.1016/j.jclepro.2020.120126.
  46. Mohamed, A., Canpolat, O. and Al-Mashhadani, M. (2022), "Mechanical and durability of geopolymer concrete containing fibers and recycled aggregate", Comput. Concrete, 30(6), 421-432. https://doi.org/10.12989/cac.2022.30.6.421.
  47. Mohammed, A.A., Tawfik, T.A., Aadi, A.S. and Hamah Sor, N. (2023), "Ultra-high performance of eco-friendly self-compacting concrete incorporated cement Kiln dust with/without waste plastic and polypropylene fiber", Innov. Infrastr. Solut., 8(3), 94. https://doi.org/10.1007/s41062-023-01058-0.
  48. Mohammed, A.S., Hilal, N.N., Ali, T.K.M. and Sor, N.H. (2021), "An investigation of the effect of walnut shell as sand replacement on the performance of cement mortar subjected to elevated temperatures", J. Phys.: Conf. Ser., 1973(1), 012034. https://doi.org/10.1088/1742-6596/1973/1/012034
  49. O z, H.O., Gesoglu, M., Guneyisi, E. and Sor, N.H. (2017), "Self-consolidating concretes made with cold-bonded fly ash lightweight aggregates", ACI Mater. J., 114(3), 385-395.
  50. Petlitckaia, S., Gharzouni, A., Vlasceanu, I.N., Tantot, O., Sobrados, I., Piancastelli, A. and Rossignol, S. (2020), "Effect of kaolin and argillite mixtures on the dielectric properties of geopolymers", Ceram. Int., 4, 100035. https://doi.org/10.1016/j.oceram.2020.100035.
  51. Phoo-ngernkham, T., Maegawa, A., Mishima, N., Hatanaka, S. and Chindaprasirt, P. (2015), "Effects of sodium hydroxide and sodium silicate solutions on compressive and shear bond strengths of FA-GBFS geopolymer", Constr. Build. Mater., 91, 1-8. https://doi.org/10.1016/j.conbuildmat.2015.05.001.
  52. Puertas, F., Palacios, M., Manzano, H., Dolado, J.S., Rico, A. and Rodriguez, J. (2011), "A model for the CASH gel formed in alkali-activated slag cements", J. Eur. Ceram. Soc., 31(12), 2043-2056. https://doi.org/10.1016/j.jeurceramsoc.2011.04.036.
  53. Puligilla, S. and Mondal, P. (2013), "Role of slag in microstructural development and hardening of fly ash-slag geopolymer", Cement Concrete Res., 43, 70-80. https://doi.org/10.1016/j.cemconres.2012.10.004.
  54. Raja, V.B., Raj, S.K., Sairam, M.D., Kasyap, A.V.R.S., Kumar, V.G., Padmapriya, R., ... and Sonawane, P.D. (2021), "Geopolymer green technology", Mater. Today: Proc., 46, 1003-1007. https://doi.org/10.1016/j.matpr.2021.01.138.
  55. Robayo-Salazar, R.A., de Gutierrez, M. and Puertas, F. (2017), "Study of synergy between a natural volcanic pozzolan and a granulated blast furnace slag in the production of geopolymeric pastes and mortars", Constr. Build. Mater., 157, 151-160. https://doi.org/10.1016/j.conbuildmat.2017.09.092.
  56. Saleh, R.D., Hilal, N. and Sor, N.H. (2022), "The impact of a large amount of ultra-fine sunflower ash with/without polypropylene fiber on the characteristics of sustainable self-compacting concrete", Iran. J. Sci. Technol. Trans. Civil Eng., 46(5), 3709-3722. https://doi.org/10.1007/s40996-022-00845-6.
  57. Santos, T.A. and Cilla, M.S. (2022), "Use of asbestos cement tile waste (ACW) as mineralizer in the production of Portland cement with low CO2 emission and lower energy consumption", J. Clean. Prod., 335, 130061. https://doi.org/10.1016/j.jclepro.2021.130061.
  58. Shi, C., Jimenez, A.F. and Palomo, A. (2011), "New cements for the 21st century: The pursuit of an alternative to Portland cement", Cement Concrete Res., 41(7), 750-763. https://doi.org/10.1016/j.cemconres.2011.03.016.
  59. Sor, H. and Abdulwahid, N.A.D.H.I.M. (2018), "The effect of superplasticizer dosage on fresh properties of self-compacting lightweight concrete produced with coarse pumice aggregate", J. Garmian Univ., 5(2), 190-209.
  60. Sor, N.H., Ali, T.K.M., Vali, K.S., Ahmed, H.U., Faraj, R.H., Bheel, N. and Mosavi, A. (2022), "The behavior of sustainable self-compacting concrete reinforced with low-density waste Polyethylene fiber", Mater. Res. Express, 9(3), 035501. https://doi.org/10.1088/2053-1591/ac58e8.
  61. Sornlar, W., Wannagon, A. and Supothina, S. (2021), "Stabilized homogeneous porous structure and pore type effects on the properties of lightweight kaolinite-based geopolymers", J. Build. Eng., 44, 103273. https://doi.org/10.1016/j.jobe.2021.103273.
  62. Tchakoute, H.K., Bewa, C.N., Fotio, D., Dieuhou, C.M., Kamseu, E. and Ruscher, C.H. (2021), "Influence of alumina on the compressive strengths and microstructural properties of the acid-based geopolymers from calcined indurated laterite and metakaolin", Appl. Clay Sci., 209, 106148. https://doi.org/10.1016/j.clay.2021.106148.
  63. Tiwari, P.K., Sharma, P., Sharma, N. and Verma, M. (2021), "An experimental investigation on metakaoline GGBS based concrete with recycled coarse aggregate", Mater. Today: Proc., 43, 1025-1030. https://doi.org/10.1016/j.matpr.2020.07.691.
  64. Tognonvi, M.T., Soro, J. and Rossignol, S. (2012), "Physical-chemistry of silica/alkaline silicate interactions during consolidation Part 1: Effect of cation size", J. Non Cryst. Solids, 358(1), 81-87. https://doi.org/10.1016/j.jnoncrysol.2011.08.027.
  65. Van Deventer, J.S., Provis, J.L. and Duxson, P. (2012), "Technical and commercial progress in the adoption of geopolymer cement", Miner. Eng., 29, 89-104. https://doi.org/10.1016/j.mineng.2011.09.009.
  66. Van Deventer, J.S., Provis, J.L., Duxson, P. and Brice, D.G. (2010), "Chemical research and climate change as drivers in the commercial adoption of alkali activated materials", Waste Biomass Valoriz., 1, 145-155. https://doi.org/10.1007/s12649-010-9015-9.
  67. Vejmelkova, E., Keppert, M., Grzeszczyk, S., Skalinski, B. and Cerny, R. (2011), "Properties of self-compacting concrete mixtures containing metakaolin and blast furnace slag", Constr. Build. Mater., 25(3), 1325-1331. https://doi.org/10.1016/j.conbuildmat.2010.09.012.
  68. Wan, Q., Rao, F., Song, S., Garcia, R.E., Estrella, R.M., Patino, C.L. and Zhang, Y. (2017), "Geopolymerization reaction, microstructure and simulation of metakaolin-based geopolymers at extended Si/Al ratios", Cement Concrete Compos., 79, 45-52. https://doi.org/10.1016/j.cemconcomp.2017.01.014.
  69. Wu, Q., Chen, Q., Huang, Z., Gu, B., Zhu, H. and Tian, L. (2020), "Preparation and characterization of porous ceramics from nickel smelting slag and metakaolin", Ceram. Int., 46(4), 4581-4586. https://doi.org/10.1016/j.ceramint.2019.10.187.
  70. Xu, H. and Van Deventer, J.S.J. (2000), "The geopolymerisation of alumino-silicate minerals", Int. J. Miner Pr., 59(3), 247-266. https://doi.org/10.1016/S0301-7516(99)00074-5.