ECO FRIENDLY CITRIC ACID-ASSISTED SOL-GEL SYNTHESIS OF HIGH-PURITY NANO SILICA FROM DIENG GEOTHERMAL SLAG: CHARACTERIZATION AND OPTIMIZATION METHOD
Authors
David C Birawidha , Azwar Manaf , Widi Astuti , Amru Daulay , Tri Haryono , Yuliana Sari , Suprihatin SuprihatinDOI:
10.29303/ipr.v8i2.486Published:
2025-05-23Issue:
Vol. 8 No. 2 (2025)Keywords:
Citric Acid, Geothermal Slag, Green Synthesis, Nano Silica, Sol-gelArticles
Downloads
How to Cite
Abstract
Geothermal slag is a by-product of the geothermal power generation process, but its added value is minimal. With a silica content of up to 70%, geothermal slag has potential as a secondary silicon source for battery silicon anode precursors. Usually, the synthesis of nano-silica was carried out through the sol-gel method, in which HCl is usually used as a modifier to regulate the physical and chemical properties of the material. But in this study chose citric acid for modifier agent because it is more environmentally friendly. The challenge of using citric acid is the formation of carbon-based salts that can cause silica blackening if not washed well. Therefore, optimization was done by adjusting the pH to produce high-purity nano-silica. The sol-gel process was carried out by adding 10% NaOH and 5N Citric Acid, with varying pH base conditions from 8 to 11. XRF analysis results showed the highest purity at pH 8. Impurities were still visible based on XRD data, and the formation of nanoparticles was confirmed through morphological analysis using FESEM and TEM where the average particle size formed is between 55 nm.References
S. N. A. Jenie, A. Ghaisani, Y. P. Ningrum, A. Kristiani, F. Aulia, and H. T. M. B. Petrus, “Preparation of silica nanoparticles from geothermal sludge via sol-gel method,” in AIP Conference Proceedings, pp. 1–6, 2018.
A. Adiatama, R. . Susanti, W. Astuti, H. T. B. . Petrus, and K. . Wanta, “Synthesis And Characteristic Of Nano Silica From Geothermal Sludge: Effect Of Surfactant,” Metalurgi, vol. 2, pp. 73–85, 2022.
R. Longval, R. Meirbekova, J. Fisher, and A. Maignot, “An Overview of Silica Scaling Reduction Technologies in the Geothermal Market,” Energies, vol. 17, no. 19, 2024.
W. U. Arifeen, J. Choi, K. Yoo, J. Shim, and T. J. Ko, “A nano-silica/polyacrylonitrile/polyimide composite separator for advanced fast charging lithium-ion batteries,” Chem. Eng. J., vol. 417, no. December 2020, p. 128075, 2021.
A. Bukowczan, E. Hebda, and K. Pielichowski, “The influence of nanoparticles on phase formation and stability of liquid crystals and liquid crystalline polymers,” J. Mol. Liq., vol. 321, p. 114849, 2021.
T. I. Janjua, Y. Cao, F. Kleitz, M. Linden, C. Yu, and A. Popat, “Silica nanoparticles: A review of their safety and current strategies to overcome biological barriers,” Adv. Drug Deliv. Rev., vol. 203, no. October, p. 115115, 2023.
N. O. Sifana and S. N. A. Jenie, “Fabrication and characterization of FITC-modified natural-based silica nanoparticles using sol-gel method,” in IOP Conference Series: Earth and Environmental Science, pp. 1–5, 2022.
N. Baig, I. Kammakakam, W. Falath, and I. Kammakakam, “Nanomaterials: A review of synthesis methods, properties, recent progress, and challenges,” Mater. Adv., vol. 2, no. 6, pp. 1821–1871, 2021.
P. Bhojane, “Recent advances and fundamentals of Pseudocapacitors: Materials, mechanism, and its understanding,” J. Energy Storage, vol. 45, no. December 2021, p. 103654, 2022.
X. Chen et al., “Conductive rigid skeleton supported silicon as high-performance Li-Ion battery anodes,” Nano Lett., vol. 12, no. 8, pp. 4124–4130, 2012.
S. B. Khan, N. li, S. Chen, J. Liang, C. Xiao, and X. Sun, “Influence of nanoparticle size on the mechanical and tribological characteristics of TiO2 reinforced epoxy composites,” J. Mater. Res. Technol., vol. 26, pp. 6001–6015, 2023.
J. Xiao et al., “Stabilization of Silicon Anode for Li-Ion Batteries,” J. Electrochem. Soc., vol. 157, no. 10, pp. A1047–A1051, 2010.
A. H. Abu Bakar and C. Jia Ni Carey, “Extraction of Silica from Rice Straw Using Alkaline Hydrolysis Pretreatment,” IOP Conf. Ser. Mater. Sci. Eng., vol. 778, no. 1, 2020.
N. N. Maseko, D. Enke, S. A. Iwarere, O. S. Oluwafemi, and J. Pocock, “Synthesis of Low Density and High Purity Silica Xerogels from South African Sugarcane Leaves without the Usage of a Surfactant,” Sustainability, vol. 15, no. 4626, pp. 1–12, 2023.
Y. L. Ni’mah, S. Suprapto, A. P. K. Subandi, N. E. Yuningsih, and A. C. Pertiwi, “The optimization of silica gel synthesis from chemical bottle waste using response surface methodology,” Arab. J. Chem., vol. 15, no. 12, p. 104329, 2022.
I. Zuwanna, M. Riza, and S. Aprilia, “The impact of solvent concentration on the characteristic of silica from rice husk ash using sol gel method,” IOP Conf. Ser. Mater. Sci. Eng., vol. 1087, no. 1, p. 012060, 2021.
F. Munawaroh, Y. Masdya, M. A. Baqiya, and T. Triwikantoro, “Synthesis and Characterization of CaO Prepared from Limestone Using Sol-Gel Method,” Indones. Phys. Rev., vol. 7, no. 2, pp. 249–258, 2024.
D. M. Shoodiqin, M. Musyarofah, F. Robiandi, and R. C. Chairunnisa, “Synthesis of Nano-Silica From Loa Kulu Rice Husk Using the Sol-Gel Method,” Indones. Phys. Rev., vol. 7, no. 1, pp. 125–132, 2024.
I. K. R. W. Artha, I. B. P. Mardana, and I. G. Arjana, “Synthesis and Characterization of Nanosilica (SiO2) Volcanic Rock of Mount Batur in Bali,” Indones. Phys. Rev., vol. 7, no. 2, pp. 268–280, 2024.
H. Bi et al., “Numerical simulation study on the formation and control of HCl during the gasification of industrial organic hazardous waste,” Process Saf. Environ. Prot., vol. 175, no. May, pp. 774–782, 2023.
A. H. Hall, D. Jacquemin, D. Henny, L. Mathieu, P. Josset, and B. Meyer, “Corrosive substances ingestion: a review,” Crit. Rev. Toxicol., vol. 49, no. 8, pp. 637–669, 2019.
I. Dudeja, R. K. Mankoo, A. Singh, and J. Kaur, “Citric acid: An ecofriendly cross-linker for the production of functional biopolymeric materials,” Sustain. Chem. Pharm., vol. 36, no. October, p. 101307, 2023.
M. H. M. Amini, R. Hashim, N. S. Sulaiman, M. Mohamed, and O. Sulaiman, “Citric acid-modified starch as an environmentally friendly binder for wood composite making,” BioResources, vol. 15, no. 2, pp. 4234–4248, 2020.
T. D. Cahyono and Syahidah, “Citric acid, an environmentally friendly adhesive and wood impregnation material-review of research,” IOP Conf. Ser. Mater. Sci. Eng., vol. 593, no. 1, 2019.
D. C. Freitas, O. Mazali, A. Sigoli, S. Francischini, M. Aur, and Z. Arruda, “The microwave-assisted synthesis of silica nanoparticles and their applications in a soy plant culture,” vol. 13, pp. 27648–27656, 2023.
D. Eissa, R. H. Hegab, A. A. Shady, and Y. H. Kotp, “Green synthesis of ZnO , MgO and SiO 2 nanoparticles and its effect on irrigation water , soil properties , and Origanum majorana productivity,” Sci. Rep., 2022.
A. B. Prasetyo et al., “Development of high purity amorphous silica from emulsifier silicon by pyrolysis process at temperature of 700 oC,” J. Phys. Conf. Ser., vol. 2190, no. 1, 2022.
P. P. Nayak, S. Nandi, K. Bhunia, and A. K. Datta, “Modelling the extraction process parameters of amorphous silica-rich rice husk ash using hybrid RSM−BPANN−MOGA optimization technique,” Mater. Chem. Phys., vol. 293, no. 126944, 2023.
Y. Kusumastuti, H. T. B. M. Petrus, F. Yohana, A. T. Buwono, and R. B. Zaqina, “Synthesis and characterization of biocomposites based on chitosan and geothermal silica,” in AIP Conference Proceedings, pp. 1–6, 2017.
D. Dhaneswara, J. F. Fatriansyah, F. W. Situmorang, and A. N. Haqoh, “Synthesis of Amorphous Silica from Rice Husk Ash: Comparing HCl and CH3COOH Acidification Methods and Various Alkaline Concentrations,” Int. J. Technol., vol. 11, no. 1, pp. 200–208, 2020.
B. Sanjuan, R. Millot, C. Dezayes, and M. Brach, “Main characteristics of the deep geothermal brine (5 km) at Soultz-sous-Forêts (France) determined using geochemical and tracer test data,” Comptes Rendus - Geosci., vol. 342, no. 7–8, pp. 546–559, 2010.
B. Sanjuan, G. Négrel, M. Le Lous, E. Poulmarch, F. Gal, and P.-C. Damy, “Main geochemical characteristics of the deep geothermal brine at Vendenheim (Alsace, France) with constraints on temperature and fluid circulation.,” in World Geothermal Congress 2020, pp. 1–12, 2020.
D. E. Edem, M. K. Abba, A. Nourian, M. Babaie, and Z. Naeem, “Experimental Study on the Interplay between Different Brine Types/Concentrations and CO2 Injectivity for Effective CO2 Storage in Deep Saline Aquifers,” Sustain., vol. 14, no. 2, 2022.
P. Martz et al., “Formation of U-rich mineralizing fluids through basinal brine migration within basement-hosted shear zones: A large-scale study of the fluid chemistry around the unconformity-related Cigar Lake U deposit (Saskatchewan, Canada),” Chemical Geology, vol. 508. pp. 116–143, 2019.
X. Luo et al., “Recovery of NaCl and Na2SO4 from high salinity brine by purification and evaporation,” Desalination, vol. 530, no. January, p. 115631, 2022.
M. Seifan, S. Mendoza, and A. Berenjian, “A comparative study on the influence of nano and micro particles on the workability and mechanical properties of mortar supplemented with fly ash,” Buildings, vol. 11, no. 2, pp. 1–17, 2021.
M. A. Al-Bedairy and H. A. Habeeb Alshamsi, “Environmentally friendly preparation of zinc oxide, study catalytic performance of photodegradation by sunlight for rhodamine B dye,” Eurasian J. Anal. Chem., vol. 13, no. 6, 2018.
W. K. You, J. P. Choi, S. M. Yoon, and J. S. Lee, “Low temperature powder injection molding of iron micro-nano powder mixture,” Powder Technol., vol. 228, no. September 2012, pp. 199–205, 2012.
R. Rajan, Y. Zakaria, S. Shamsuddin, and N. F. Nik Hassan, “Robust synthesis of mono-dispersed spherical silica nanoparticle from rice husk for high definition latent fingermark development,” Arab. J. Chem., vol. 13, no. 11, pp. 8119–8132, 2020.
D. S. Choi, J. H. Choi, and C. Y. Lee, “Structural colors based on amorphous arrays comprised solely of silica particles,” Appl. Sci., vol. 10, no. 1, 2020.
License

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Authors who publish with Indonesian Physical Review Journal, agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution-ShareAlike 4.0 International Licence (CC BY SA-4.0). This license allows authors to use all articles, data sets, graphics, and appendices in data mining applications, search engines, web sites, blogs, and other platforms by providing an appropriate reference. The journal allows the author(s) to hold the copyright without restrictions and will retain publishing rights without restrictions.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in Indonesian Physical Review Journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).