Sustainable valorisation of fly ash into geopolymer-based adsorbent: structural optimization and methylene-blue removal performance

Khoa Dang Nguyen1, Anh Thi Kim Phan1, Anh Phuong Le Thi2, Sujitra Onutai3, Ky Ngoc Hoa Nguyen4

Affiliation:

1 Faculty of Environment, Van Lang School of Technology, Van Lang University, Binh Loi Trung Ward, Ho Chi Minh City 70000, Vietnam 2 Research Center for Negative Emissions Technologies, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan 3 Key Laboratory of Advanced Materials of Tropical Island Resources of Ministry of Education, School of Materials Science and Engineering, Hainan University, Hainan, 570228, PR China 4 Faculty of Basic Sciences, University of Phan Thiet, Lam Dong Province, 77100, Vietnam khoa.nd@vlu.edu.vn

DOI:

https://doi.org/10.23939/chcht20.01.010

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Abstract:

In this study, fly ash (FA)-based geopolymers were synthesized using varying proportions of sodium silicate/sodium hydroxide (Na₂SiO₃/ NaOH 10M) solution, ranging from 49% in the 51FA sample to 67% in the 33FA sample, used for the adsorption of methylene blue (MB) in water. Following curing at 60°C for 24 h, the porosity of the resulting geopolymers decreased, attributed to the enhanced polycondensation process driven by the increased Na₂SiO₃ content, which resulted in the formation of a more compact gel structure in the obtained geopolymer. The Weber–Morris model indicated that surface interactions with MB molecules were predominant in the 51FA sample, while pore-filling mechanisms were more pronounced in the 33FA geopolymer. Adsorption experiments revealed that all geopolymer samples conformed to the Langmuir isotherm model, with correlation coefficients approaching unity.

References:

[1] Pham, N. Q.; Le, K. A. Coal Fly Ash in Vietnam and its Application as a Lightweight Material. Chem. Eng. Trans. 2021, 83, 31-36. https://doi.org/10.3303/CET2183006

[2] Mathapati, M.; Amate, K.; Durga Prasad, C.; Jayavardhana, M. L.; Hemanth Raju, T. A Review on Fly Ash Utilization. Mater. Today Proc. 2022, 50, 1535-1540. https://doi.org/10.1016/j.matpr.2021.09.106
https://doi.org/10.1016/j.matpr.2021.09.106

[3] Li, H.; Xu, D. The Future Resources for eco-Building Materials: II. Fly ash And Coal Waste. J. Wuhan Univ. Technol.-Mat. Sci. Edit. 2009, 24, 667-672. http://doi.org/10.1007/s11595-009-4667-7
https://doi.org/10.1007/s11595-009-4667-7

[4] Rao, Z.; Yu, W.; Yuan, H.; Wei, P.; Yang, F.; Nyarko-Appiah, J. E. Eco-Friendly and Efficient Alumina Recovery from Coal Fly Ash by Employing the CaO as an Additive During the Vacuum Carbothermic Reduction and Alkali Dissolution. J. Sustain. Metall. 2024, 10, 2216-2226 http://doi.org/10.1007/s40831-024-00916-0
https://doi.org/10.1007/s40831-024-00916-0

[5] Davidovits, J. Geopolymers: Inorganic Polymeric New Materials. J. Therm. Anal. Calorim. 1991, 37, 1633-1656. http://doi.org/10.1007/BF01912193
https://doi.org/10.1007/BF01912193

[6] Onutai, S.; Kobayashi, T.; Thavorniti, P.; Jiemsirilers, S. Porous Fly Ash-Based Geopolymer Composite Fiber as an Adsorbent for Removal of Heavy Metal Ions from Wastewater. Mater. Lett. 2019, 236, 30-33. https://doi.org/10.1016/j.matlet.2018.10.035
https://doi.org/10.1016/j.matlet.2018.10.035

[7] Onutai, S.; Jiemsirilers, S.; Thavorniti, P.; Kobayashi, T. Aluminium Hydroxide Waste Based Geopolymer Composed of Fly Ash for Sustainable Cement Materials. Constr. Build. Mater. 2015, 101, 298-308. https://doi.org/10.1016/j.conbuildmat.2015.10.097
https://doi.org/10.1016/j.conbuildmat.2015.10.097

[8] Novais, R. M.; Carvalheiras, J.; Tobaldi, D. M.; Seabra, M. P.; Pullar, R. C.; Labrincha, J. A. Synthesis of Porous Biomass Fly Ash-Based Geopolymer Spheres for Efficient Removal of Methylene Blue from Wastewaters. J. Clean. Prod. 2019, 207, 350-362. https://doi.org/10.1016/j.jclepro.2018.09.265
https://doi.org/10.1016/j.jclepro.2018.09.265

[9] Maleki, A.; Mohammad, M.; Emdadi, Z.; Asim, N.; Azizi, M.; Safaei, J. Adsorbent Materials Based on a Geopolymer Paste for Dye Removal from Aqueous Solutions. Arab. J. Chem. 2020, 13, 3017-3025. https://doi.org/10.1016/j.arabjc.2018.08.011
https://doi.org/10.1016/j.arabjc.2018.08.011

[10] Onutai, S. In Development of geopolymer materials sourced with fly ash and industrial waste, 2016.

[11] Pimraksa, K.; Chindaprasirt, P.; Rungchet, A.; Sagoe-Crentsil, K.; Sato, T. Lightweight Geopolymer Made of Highly Porous Siliceous Materials with Various Na2O/Al2O3 and SiO2/Al2O3 Ratios. Mater. Sci. Eng. A 2011, 528, 6616-6623. https://doi.org/10.1016/j.msea.2011.04.044
https://doi.org/10.1016/j.msea.2011.04.044

[12] Nguyen, K. D.; Tran, A. T. H.; Kaus, N. H. M. Preparation and Characterization of Red Mud-Based Geopolymer Composited with Rice Husk Ash for the Adsorption of Bromocresol Green in Aqueous Solution. Chem. Chem. Technol. 2023, 17, 857-869. https://doi.org/10.23939/chcht17.04.857
https://doi.org/10.23939/chcht17.04.857

[13] Yao, X.; Zhang, Z.; Zhu, H.; Chen, Y. Geopolymerization Process of Alkali-Metakaolinite Characterized by Isothermal Calorimetry. Thermochimica Acta 2009, 493, 49-54. https://doi.org/10.1016/j.tca.2009.04.002
https://doi.org/10.1016/j.tca.2009.04.002

[14] Sasui, S.; Kim, G.; van Riessen, A.; Lim, C.; Eu, H.; Park, J.; Nam, J. Effects of Na2SiO3/NaOH Ratio in Alkali Activator on the Microstructure, Strength and Chloride Ingress in fly Ash and GGBS Based Alkali Activated Concrete. J. Build. Eng. 2024, 98, 111255. https://doi.org/10.1016/j.jobe.2024.111255
https://doi.org/10.1016/j.jobe.2024.111255

[15] Salleh, M. A. M.; Mahmoud, D. K.; Karim, W. A.; Idris, A. Cationic and Anionic Dye Adsorption By Agricultural Solid Wastes: A Comprehensive Review. Desalination 2011, 280, 1-13. https://doi.org/10.1016/j.desal.2011.07.019
https://doi.org/10.1016/j.desal.2011.07.019

[16] Ma, G.; Zhu, Y.; Zhang, Z.; Li, L. Preparation and Characterization of Multi-Walled Carbon Nanotube/TiO2 Composites: Decontamination Organic Pollutant in Water. Appl. Surf. Sci. 2014, 313, 817-822. https://doi.org/10.1016/j.apsusc.2014.06.079
https://doi.org/10.1016/j.apsusc.2014.06.079

[17] Chen, Q.; He, Q.; Lv, M.; Xu, Y.; Yang, H.; Liu, X.; Wei, F. Selective Adsorption of Cationic Dyes by UiO-66-NH2. Appl. Surf. Sci. 2015, 327, 77-85. https://doi.org/10.1016/j.apsusc.2014.11.103
https://doi.org/10.1016/j.apsusc.2014.11.103

[18] Takele, T.; Angassa, K.; Abewaa, M.; Kebede, A. M.; Tessema, I. Adsorption of Methylene Blue from Textile Industrial Wastewater Using Activated Carbon Developed from H3PO4-Activated Khat Stem Waste. Biomass Convers. Biorefin. 2025, 15, 4085-4108. http://doi.org/10.1007/s13399-023-05245-y
https://doi.org/10.1007/s13399-023-05245-y

[19] el Alouani, M.; Alehyen, S.; el Achouri, M.; Taibi, M. H. Removal of Cationic Dye - Methylene Blue- from Aqueous Solution by Adsorption on Fly Ash-Based Geopolymer. J. Mater. Environ. Sci. 2018, 9, 32-46. http://doi.org/10.26872/jmes.2018.9.1.5
https://doi.org/10.26872/jmes.2018.9.1.5

[20] Modi, S.; Yadav, V. K.; Gacem, A.; Ali, I. H.; Dave, D.; Khan, S. H.; Yadav, K. K.; Rather, S.-u.; Ahn, Y.; Son, C. T.; et al. Recent and Emerging Trends in Remediation of Methylene Blue Dye from Wastewater by Using Zinc Oxide Nanoparticles. Water 2022, 14, 1749. http://doi.org/10.3390/w14111749
https://doi.org/10.3390/w14111749

[21] Yang, Y.; Le, T.-C.-D.; Kudo, I.; Do, T.-M.-D.; Niihara, K.; Suematsu, H.; Thorogood, G. Pore-Forming Process in Dehydration of Metakaolin-Based Geopolymer. International Journal of Ceramic Engineering & Science 2021, 30, 211-216. https://doi.org/10.1002/ces2.10100
https://doi.org/10.1002/ces2.10100

[22] Sulistiyo, Y. A.; Andriana, N.; Piluharto, B.; Zulfikar, Z. Silica Gels from Coal Fly Ash as Methylene Blue Adsorbent: Isotherm and Kinetic Studies. Bull. Chem. React. Eng. Catal. 2017, 12, 10. http://doi.org/10.9767/bcrec.12.2.766.263-272
https://doi.org/10.9767/bcrec.12.2.766.263-272

[23] Sinha, D. K.; Kumar, A.; K.; Kumar, S. Development of Geopolymer Concrete from Fly Ash and Bottom Ash Mixture. Trans. Indian Ceram. Soc. 2014, 73, 143-148. https://doi.org/10.1080/0371750X.2014.922427
https://doi.org/10.1080/0371750X.2014.922427

[24] Petrus, H. T.; Olvianas, M.; Shafiyurrahman, M. F.; Pratama, I. G.; Jenie, S. N.; Astuti, W.; Nurpratama, M. I.; Ekaputri, J. J.; Anggara, F. Circular Economy of Coal Fly Ash and Silica Geothermal for Green Geopolymer: Characteristic and Kinetic Study. Gels 2022, 8, 233 http://doi.org/10.3390/gels8040233
https://doi.org/10.3390/gels8040233

[25] Dupuis, R.; Pellenq, R.; Champenois, J.-B.; Poulesquen, A. Dissociation Mechanisms of Dissolved Alkali Silicates in Sodium Hydroxide. J. Phys. Chem. C. 2020, 124, 8288-8294. http://doi.org/10.1021/acs.jpcc.0c01495
https://doi.org/10.1021/acs.jpcc.0c01495

[26] Matinfar, M.; Nychka, J. A. A review of Sodium Silicate Solutions: Structure, Gelation, and Syneresis. Adv. Colloid Interface Sci. 2023, 322, 103036. https://doi.org/10.1016/j.cis.2023.103036
https://doi.org/10.1016/j.cis.2023.103036

[27] Adewuyi, Y. G. Recent Advances in Fly-Ash-Based Geopolymers: Potential on the Utilization for Sustainable Environmental Remediation. ACS Omega 2021, 6, 15532-15542. http://doi.org/10.1021/acsomega.1c00662
https://doi.org/10.1021/acsomega.1c00662

[28] Luhar, I.; Luhar, S. A Comprehensive Review on Fly Ash-Based Geopolymer. J. Compos. Sci. 2022, 6, 219 http://doi.org/10.3390/jcs6080219
https://doi.org/10.3390/jcs6080219

[29] Rahman, M. M.; Muttakin, M.; Pal, A.; Shafiullah, A. Z.; Saha, B. B. A Statistical Approach to Determine Optimal Models for IUPAC-Classified Adsorption Isotherms. Energies 2019, 12, 4565 http://doi.org/10.3390/en12234565
https://doi.org/10.3390/en12234565

[30] Rattanasak, U.; Chindaprasirt, P. Influence of NaOH solution on the synthesis of fly ash geopolymer. Miner. Eng. 2009, 22, 1073-1078. https://doi.org/10.1016/j.mineng.2009.03.022
https://doi.org/10.1016/j.mineng.2009.03.022

[31] Guerrieri, M.; Sanjayan, J.; Mohd Ali, A. Z. Geopolymer damage due to leaching when exposed to water. In Concrete Durability and Service Life Planning; Kovler, K.; Zhutovsky, S.; Spatari, S.; Jensen, O. M., Eds.; Springer International Publishing, Cham, 2020; pp 74-78.
https://doi.org/10.1007/978-3-030-43332-1_15

[32] Lv, X.-s.; Qin, Y.; Lin, Z.-x.; Tian, Z.-k.; Cui, X.-m. Inhibition of Efflorescence in Na-Based Geopolymer Inorganic Coating. ACS Omega 2020, 5, 14822-14830. http://doi.org/10.1021/acsomega.0c01919
https://doi.org/10.1021/acsomega.0c01919

[33] Morsy, M. S.; Alsayed, S. H.; Al-Salloum, Y.; Almusallam, T. Effect of Sodium Silicate to Sodium Hydroxide Ratios on Strength and Microstructure of Fly Ash Geopolymer Binder. Arab. J. Sci. Eng. 2014, 39, 4333-4339. http://doi.org/10.1007/s13369-014-1093-8
https://doi.org/10.1007/s13369-014-1093-8

[34] Matinfar, M.; Nychka, J. A. Process Mapping of the Sol-Gel Transition in Acid-Initiated Sodium Silicate Solutions. Gels 2024, 10, 673 http://doi.org/10.3390/gels10100673
https://doi.org/10.3390/gels10100673

[35] Kwek, S. Y.; Awang, H.; Cheah, C. B. Influence of Liquid-to-Solid and Alkaline Activator (Sodium Silicate to Sodium Hydroxide) Ratios on Fresh and Hardened Properties of Alkali-Activated Palm Oil Fuel Ash Geopolymer Materials 2021, 14, 4253. https://doi.org/10.3390/ma14154253
https://doi.org/10.3390/ma14154253

[36] Efe, M.; Öz, A.; Bayrak, B.; Kaplan, G.; Aydın, A. C. Effect of Na2SiO3/NaOH Rate and Natural Zeolite Content on Basalt Fiber Reinforced Eco-Efficient Slag-Based Geopolymer Mortar Synthesis. Arch. Civ. Mech. Eng. 2024, 24, 215. http://doi.org/10.1007/s43452-024-01021-5
https://doi.org/10.1007/s43452-024-01021-5

[37] Katoueizadeh, E.; Rasouli, M.; Zebarjad, S. M. A Comprehensive Study on the Gelation Process of Silica Gels from Sodium Silicate. J. Mater. Res. Technol. 2020, 9, 10157-10165. https://doi.org/10.1016/j.jmrt.2020.07.020
https://doi.org/10.1016/j.jmrt.2020.07.020

[38] Kugbe, J.; Matsue, N.; Henmi, T. Synthesis of Linde Type A zeolite-Goethite Nanocomposite as an Adsorbent for Cationic and Anionic Pollutants. J. Hazard. Mater. 2009, 164, 929-935. https://doi.org/10.1016/j.jhazmat.2008.08.080
https://doi.org/10.1016/j.jhazmat.2008.08.080

[39] Nguyen, K. D.; My, Q. N. V.; Kim, A. P. T.; Tran, P. T.; Huynh, D. T. K.; Le, O. T. K. Coal Fly Ash-Slag and Slag-Based Geopolymer as an Absorbent for the Removal of Methylene Blue in Wastewater. STDJ 2022, 25, 2215-2223. https://doi.org/10.32508/stdj.v25i1.3421
https://doi.org/10.32508/stdj.v25i1.3421

[40] Rivera-Muñoz, E. M.; Nava, R.; Velázquez-Castillo, R.; Manzano-Ramírez, A.; Ramón, J.; Apátiga-Castro, M.; Rodríguez-López, A. Ion Exchange in Geopolymers. In New Trends in Ion Exchange Studies, Karakuş, S., Ed.; IntechOpen: Rijeka, 2018. http://doi.org/10.5772/intechopen.80970
https://doi.org/10.5772/intechopen.80970

[41] Li, C. J.; Zhang, Y. J.; Chen, H.; He, P. Y.; Meng, Q. Development of Porous and Reusable Geopolymer Adsorbents for Dye Wastewater Treatment. J. Clean. Prod. 2022, 348, 131278. https://doi.org/10.1016/j.jclepro.2022.131278
https://doi.org/10.1016/j.jclepro.2022.131278

[42] El Alouani, M.; Alehyen, S.; El Achouri, M.; Taibi, M. h. Adsorption of Cationic Dye onto Fly Ash-Based Geopolymer: Batch and Fixed Bed Column Studies. MATEC Web Conf. 2018, 149, 02088.
https://doi.org/10.1051/matecconf/201814902088

[43] Hasani, N.; Selimi, T.; Mele, A.; Thaçi, V.; Halili, J.; Berisha, A.;Sadiku, M. Theoretical, Equilibrium, Kinetics and Thermodynamic Investigations of Methylene Blue Adsorption onto Lignite Coal. Molecules 2022, 27, 1856. https://doi.org/10.3390/molecules27061856
https://doi.org/10.3390/molecules27061856

[44] Heah, C. Y.; Kamarudin, H.; Bakri, A. M. M. A.; Binhussain, M.; Luqman, M.; Nizar, I. K.; Ruzaidi, C. M.; Liew, Y. M. Effect of Curing Profile on Kaolin-based Geopolymers. Phys. Procedia 2011, 22, 305-311. https://doi.org/10.1016/j.phpro.2011.11.048
https://doi.org/10.1016/j.phpro.2011.11.048

[45] Komnitsas, K.; Zaharaki, D. Geopolymerisation: A Review and Prospects for the Minerals Industry. Miner. Eng. 2007, 20, 1261-1277. https://doi.org/10.1016/j.mineng.2007.07.011
https://doi.org/10.1016/j.mineng.2007.07.011

[46] Singh, B.; Ishwarya, G.; Gupta, M.; Bhattacharyya, S. K. Geopolymer Concrete: A Review of Some Recent Developments. Constr. Build. Mater. 2015, 85, 78-90. https://doi.org/10.1016/j.conbuildmat.2015.03.036
https://doi.org/10.1016/j.conbuildmat.2015.03.036

[47] Temuujin, J.; Minjigmaa, A.; Lee, M.; Chen-Tan, N.; van Riessen, A. Characterisation of Class F fly Ash Geopolymer Pastes Immersed in Acid and Alkaline Solutions. Cem. Concr. Compos. 2011, 33, 1086-1091. https://doi.org/10.1016/j.cemconcomp.2011.08.008
https://doi.org/10.1016/j.cemconcomp.2011.08.008

[48] Bakharev, T. Geopolymeric materials prepared using Class F fly ash and elevated temperature curing. Cem. Concr. Res. 2005, 35, 1224-1232. https://doi.org/10.1016/j.cemconres.2004.06.031
https://doi.org/10.1016/j.cemconres.2004.06.031

[49] Zhou, Y.; Zhang, M.; Hu, X.; Wang, X.; Niu, J.; Ma, T. Adsorption of Cationic Dyes on a Cellulose-Based Multicarboxyl Adsorbent. J. Chem. Eng. Data 2013, 58, 413-421. http://doi.org/10.1021/je301140c
https://doi.org/10.1021/je301140c

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Sustainable valorisation of fly ash into geopolymer-based adsorbent: structural optimization and methylene-blue removal performance

Keywords: