References

  1. J. Davidovits, Geopolymers and geopolymeric materials, J. Therm. Anal., 35 (1989) 429–441.
  2. P.G. He, M.R. Wang, S. Fu, D.C. Jia, S. Yan, J.K. Yuan, J.H. Xu, P.F. Wang, Y. Zhou, Effects of Si/Al ratio on the structure and properties of metakaolin based geopolymer, Ceram. Int., 42 (2016) 14416–14422.
  3. G.S. Wang, Y.W. Ma, Drying shrinkage of alkali-activated fly ash/slag blended system, J. Sustainable Cem.-Based Mater., 7 (2018) 203–213.
  4. R.M. Novais, M.P. Seabra, J.A. Labrincha, Porous geopolymer spheres as novel pH buffering materials, J. Cleaner Prod., 143 (2017) 1114–1122.
  5. Y. Zhang, P.G. He, J.K. Yuan, C. Yang, D.C. Jia, Y. Zhou, Effects of graphite on the mechanical and microwave absorption properties of geopolymer based composites, Ceram. Int., 43 (2017) 2325–2332.
  6. B.L. El-Eswed, O.M. Aldagag, F.I. Khalili, Efficiency and mechanism of stabilization/solidification of Pb(II), Cd(II), Cu(II), Th(IV) and U(VI) in metakaolin based geopolymers, Appl. Clay Sci., 140 (2017) 148–156.
  7. S. Onutai, T. Kobayashi, P. Thavorniti, S. Jiemsirilers, Porous fly ash-based geopolymer composite fiber as an adsorbent for removal of heavy metal ions from wastewater, Mater. Lett., 236 (2019) 30–33.
  8. Q. Tang, G.-H. Xue, S.-J. Yang, K.T. Wang, X.-M. Cui, Study on the preparation of a free-sintered inorganic polymerbased proppant using the suspensions solidification method, J. Cleaner Prod., 148 (2017) 276–282.
  9. A. Madi Balo, H. Rahier, A. Mobili, A. Katsiki, N. Fagel, U. Melo Chinje, D. Njopwouo, Metakaolin-based inorganic polymer synthesis using cotton shell ash as sole alkaline activator, Constr. Build. Mater., 191 (2018) 1011–1022.
  10. F.L. Fu, Q. Wang, Removal of heavy metal ions from wastewaters: a review, J. Environ. Manage., 92 (2011) 407–418.
  11. P.-S. Keng, S.-L. Lee, S.-T. Ha, Y.-T. Hung, S.-T. Ong, Removal of hazardous heavy metals from aqueous environment by lowcost adsorption materials, Environ. Chem. Lett., 12 (2014) 15–25.
  12. N.H. Abdullah, K. Shameli, E.C. Abdullah, L.C. Abdullah, Solid matrices for fabrication of magnetic iron oxide nanocomposites: synthesis, properties, and application for the adsorption of heavy metal ions and dyes, Composites, Part B, 162 (2019) 538–568.
  13. B.M. Ibrahim, N.A. Fakhre, Crown ether modification of starch for adsorption of heavy metals from synthetic wastewater, Int. J. Biol. Macromol., 123 (2019) 70–80.
  14. I. Kara, D. Tunc, F. Sayin, S.T. Akar, Study on the performance of metakaolin based geopolymer for Mn(II) and Co(II) removal, Appl. Clay Sci., 161 (2018) 184–193.
  15. I. Kara, D. Yilmazer, S.T. Akar, Metakaolin based geopolymer as an effective adsorbent for adsorption of zinc(II) and nickel(II) ions from aqueous solutions, Appl. Clay Sci., 139 (2017) 54–63.
  16. V. Nejadshafiee, M.R. Islami, Adsorption capacity of heavy metal ions using sultone-modified magnetic activated carbon as a bio-adsorbent, Mater. Sci. Eng., C, 101 (2019) 42–52.
  17. Z.L. Du, T. Zheng, P. Wang, Experimental and modelling studies on fixed bed adsorption for Cu(II) removal from aqueous solution by carboxyl modified jute fiber, Powder Technol., 338 (2018) 952–959.
  18. A.V. Dmitriev, E.V. Vladimirova, M.V. Kandaurov, D.G. Kellerman, A.Y. Chufarov, A.P. Tyutyunnik, Hollow spheres of BiFeO3: synthesis and properties, J. Alloys Compd., 743 (2018) 654–657.
  19. H. Ge, H.B. Xu, T.Y. Lu, J. Li, H.S. Chen, J.D. Wan, Microfluidic production of porous carbon spheres with tunable size and pores, J. Colloid Interface Sci., 461 (2016) 168–172.
  20. Q. Tang, Y.-Y. Ge, K.-T. Wang, Y. He, X.-M. Cui, Preparation and characterization of porous metakaolin-based inorganic polymer spheres as an adsorbent, Mater. Des., 88 (2015) 1244–1249.
  21. X. Zhao, W. Li, F.G. Kong, H.L. Chen, Z.Q. Wang, S.X. Liu, C.D. Jin, Carbon spheres derived from biomass residue via ultrasonic spray pyrolysis for supercapacitors, Mater. Chem. Phys., 219 (2018) 461–467.
  22. Y.Y. Ge, Y. Yuan, K.T. Wang, Y. He, X.M. Cui, Preparation of geopolymer-based inorganic membrane for removing Ni2+ from wastewater, J. Hazard. Mater., 299 (2015) 711–718.
  23. C.M. Li, Y. He, Q. Tang, K.-T. Wang, X.-M. Cui, Study of the preparation of CdS on the surface of geopolymer spheres and photocatalyst performance, Mater. Chem. Phys., 178 (2016) 204–210.
  24. Y.Y. Ge, X.M. Cui, Y. Kong, Z.L. Li, Y. He, Q.Q. Zhou, Porous geopolymeric spheres for removal of Cu(II) from aqueous solution: synthesis and evaluation, J. Hazard. Mater., 283 (2015) 244–251.
  25. T. Luukkonen, M. Sarkkinen, K. Kemppainen, J. Rämö, U. Lassi, Metakaolin geopolymer characterization and application for ammonium removal from model solutions and landfill leachate, Appl. Clay Sci., 119 (2016) 266–276.
  26. T.W. Cheng, M.L. Lee, M.S. Ko, T.H. Ueng, S.F. Yang, The heavy metal adsorption characteristics on metakaolin-based geopolymer, Appl. Clay Sci., 56 (2012) 90–96.
  27. Q. Tang, K. Wang, M. Yaseen, Z. Tong, X. Cui, Synthesis of highly efficient porous inorganic polymer microspheres for the adsorptive removal of Pb(II) from wastewater, J. Cleaner Prod., 193 (2018) 351–362.
  28. B.-H. Mo, H. Zhu, X.-M. Cui, Y. He, S.-Y. Gong, Effect of curing temperature on geopolymerization of metakaolin-based geopolymers, Appl. Clay Sci., 99 (2014) 144–148.
  29. M. Basu, A.K. Guha, L. Ray, Adsorption of lead on lentil husk in fixed bed column bioreactor, Bioresour. Technol., 283 (2019) 86–95.
  30. S. Chatterjee, S. Mondal, S. De, Design and scaling up of fixed bed adsorption columns for lead removal by treated laterite, J. Cleaner Prod., 177 (2018) 760–774.
  31. M.H. Zhang, H. Dong, Z.F. Geng, Computational study of particle packing process and fluid flow inside Polydisperse cylindrical particles fixed beds, Powder Technol., 354 (2019) 19–29.
  32. J.J. Qu, T. Song, J.S. Liang, X. Bai, Y. Li, Y.N. Wei, S.Q. Huang, L.Y. Dong, Y. Jin, Adsorption of lead(II) from aqueous solution by modified Auricularia matrix waste: a fixed-bed column study, Ecotoxicol. Environ. Saf., 169 (2019) 722–729.