Abstract
Arsenic (III) ion contamination in water system is a significant and challenging global concern. In this study, agro-waste material, specifically Citrus pseudolimon peels (CP), was utilized as a precursor for the preparation of biochar (CPB). Furthermore, biochar-supported Fe₃O₄-Zn + Al layered double hydroxide (M-CPB/LDH) has been synthesized by simple co-precipitation method for the removal of noxious As (III) ions. The prepared composites undergone instrumental analysis including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) equipped with energy-dispersive X-ray spectroscopy (EDX) and elemental mapping, high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET), thermo-gravimetric (TGA), vibrating sample magnetometer (VSM), and X-ray photoelectron spectroscopy (XPS). The surface areas (BET) of CPB and M-CPB/LDH composites were recorded to be 52.49 m²/g and 99.78 m²/g, respectively. The VSM analysis confirmed the ferromagnetic characteristics of M-CPB/LDH composites. The adsorption behavior of CPB, M-LDH and M-CPB/LDH composites was strongly depend on pH, with the maximum As (III) ion uptake recorded at pH 4.0. The sorption of As (III) ion were analyzed by isotherm, kinetics and thermodynamic study. Experimental data obey the Langmuir model (R2 = 0.97–0.99), indicating that As (III) ions exhibits the monolayer adsorption. The kinetic results directed that removal mechanism conformed to pseudo-second-order model, signifying the chemisorption play a major role. The maximum monolayer capacities of CPB, M-LDH and M-CPB/LDH composites for As (III) ions were recorded to be 575.10 mg/g, 624.34 mg/g and 721.34 mg/g, respectively. The maximum adsorption of 88.95%, 92.18%, and 96.76% were achieved for CPB, M-LDH and M-CPB/LDH composites, respectively, at 65 °C under optimal conditions, indicating a endothermic and thermodynamically favorable. Regeneration study demonstrated that adsorbents were effectively recovered using 0.01 mol/L HCl as the desorbing agent. After seven adsorption-desorption cycles, the adsorption remained at 78.19%, 83.13%, and 91.45% for CPB, M-LDH, and M-CPB/LDH composites, respectively. Finally, we summarize that synthesized M-CPB/LDH composite exhibited high efficiency, versatility and economical for As (III) ion removal, making it a promising material for wastewater treatment.
Data availability
Data will be made available from the corresponding author on a request.
References
Bessaies, H. et al. Synthesis of novel adsorbent by intercalation of biopolymer in LDH for the removal of arsenic from synthetic and natural water. J. Environ. Sci. 91, 246–261 (2020).
Turk, T., Boyraz, T. & Alp, İ. Arsenic removal by layered double hydroxides (LDH): A mini review. Water Pract. Technol. 19 (5), 2088–2107 (2024).
Brahma, D., Barman, M. P., Basak, D. & Saikia, H. Prospects of Layered Double Hydroxide (LDH)-based Adsorbents for the Remediation of Environmental Inorganic Pollutants from Wastewater: a Critical Review (Environmental Science. Water Res Technol, 2025).
Adlnasab, L., Shekari, N. & Maghsodi, A. Optimization of arsenic removal with Fe3O4@ Al2O3@ Zn-Fe LDH as a new magnetic nano adsorbent using Box-Behnken design. J. Environ. Chem. Eng. 7 (2), 102974 (2019).
Borges, G. A. et al. Adsorption of organic and inorganic arsenic from aqueous solutions using MgAl-LDH with incorporated Nitroprusside. J. Colloid Interface Sci. 575, 194–205 (2020).
Yadav, M. K., Gupta, A. K., Ghosal, P. S. & Mukherjee, A. Modeling and analysis of adsorptive removal of arsenite by Mg–Fe–(CO3) layer double hydroxide with its application in real-life groundwater. J. Environ. Sci. Health. 54 (13), 1318–1336 (2019).
Hong, J., Zhu, Z., Lu, H. & Qiu, Y. Synthesis and arsenic adsorption performances of ferric-based layered double hydroxide with α-alanine intercalation. Chem. Eng. J. 252, 267–274 (2014).
Li, S. et al. Dual-functional sites for selective adsorption of mercury and arsenic ions in [SnS4] 4-/MgFe-LDH from wastewater. J. Hazard. Mater. : 403, 123940. (2021).
Sun, Y. et al. Research progress on adsorption of arsenic from water by modified Biochar and its mechanism: A review. Water 14 (11), 1691 (2022).
Meng, Z. et al. Simultaneous arsenate and alkali removal from alkaline wastewater by in-situ formation of Zn–Al layered double hydroxide. Micropor Mesopor Mat. 227, 137–143 (2016).
Bagherifam, S. et al. Evaluation of Zn–Al–SO4 layered double hydroxide for the removal of arsenite and arsenate from a simulated soil solution: isotherms and kinetics. Appl. Clay Sci. 95, 119–125 (2014).
Mandal, S., Sahu, M. K. & Patel, R. K. Adsorption studies of arsenic (III) removal from water by zirconium polyacrylamide hybrid material (ZrPACM-43). Water Resour. Ind. 4, 51–67 (2013).
Kasneryk, V. et al. From Zn-Al LDH to ZIF-8@ Zn-Al LDH conversion coatings on the surface of AA2024 alloy: inside the process and the effect of the transformation on the protective properties. S&I: 105958. (2025).
Ardau, C., Frau, F. & Lattanzi, P. New data on arsenic sorption properties of Zn–Al sulphate layered double hydroxides: influence of competition with other anions. Appl. Clay Sci. 80, 1–9 (2013).
Li, A., Deng, H., Ye, C. & Jiang, Y. Fabrication and characterization of novel ZnAl-layered double hydroxide for the superadsorption of organic contaminants from wastewater. ACS Omega. 5 (25), 15152–15161 (2020).
Ma, X., Li, S., Ren, H., Zhang, Y. & Ma, Z. Egg white-mediated fabrication of Mg/Al-LDH-hard Biochar composite for phosphate adsorption. Molecules 27 (24), 8951 (2022).
Yang, Q. et al. In situ stabilization of the adsorbed Co2 + and Ni2 + in rice straw Biochar based on LDH and its reutilization in the activation of peroxymonosulfate. J. Hazard. Mater. 416, 126215 (2021).
Li, S. et al. Adsorption and mechanistic study of the invasive plant-derived Biochar functionalized with CaAl-LDH for Eu (III) in water. J. Environ. Sci. : 96, 127–137. (2020).
Xue, L. et al. High efficiency and selectivity of MgFe-LDH modified wheat-straw Biochar in the removal of nitrate from aqueous solutions. J. Taiwan. Inst. Chem. Eng. 63, 312–317 (2016).
Nguyen, T. M. et al. Removal of Tetracycline from aqueous solution using composite adsorbent of ZnAl layered double hydroxide and Bagasse Biochar. Environ. Techno Innov. : 28, 102914. (2022).
Bai, Y. et al. Synthesis of Zn/Al layered double hydroxides magnetic-nanoparticle for removal of humic acid. DESALIN. WATER TREAT. 317, 100097 (2024).
Wang, Y. et al. Recent progress in carbon-based materials for supercapacitor electrodes: a review. J. Mater. Sci. 56, 173–200 (2021).
Li, N. et al. Harnessing corn straw biochar: A breakthrough in eco-friendly Cu(II) wastewater treatment. Waste Manage. 197, 25–34 (2025).
Dinh, T. D., Zhang, D. & Tuan, V. N. High iodine adsorption performances under off-gas conditions by bismuth-modified ZnAl-LDH layered double hydroxide. RSC Adv. 10 (24), 14360–14367 (2020).
Wang, J. et al. Arsenic removal from water/wastewater using layered double hydroxide derived adsorbents, a critical review. RSC Adv. 8 (40), 22694–22709 (2018).
Yang, H. et al. High-value utilization of agricultural waste: A study on the catalytic performance and deactivation characteristics of iron-nickel supported biochar-based catalysts in the catalytic cracking of toluene. Energy 323, 135806 (2025).
Adaileh, A. et al. Development of Cu-ZnO ZrO₂ based polyacrylonitrile polymer composites for removing pharmaceutical pollutants and heavy metals from wastewater. Sci. Rep. 15 (1), 22250 (2025).
Lawal, S. Y., Batagarawa, S. M. & Musa, A. Effect of citrus sinensis peel-derived Biochar on the concentrations of heavy metals in soil irrigated with municipal wastewater. JJBRPAC 1 (1), 18–22 (2024).
Shen, Z. et al. Synthesis of MgO-coated corncob Biochar and its application in lead stabilization in a soil washing residue. Environ. Int. 122, 357–362 (2019).
Fouad, G., Amin, H. S., Ahmed I, A. S. & A Ali, A. Zinc-aluminium layered double hydroxides: Fabrication, study and adsorption application for removal organic dye from aqueous media. Benha J. Appl. Sci. 7 (4), 53–61 (2022).
Manjula Rani, K. & Palanisamy, P. N. Synthesis and characterization of mesoporous, nanostructured zinc aluminium carbonate layered double hydroxides (ZAC-LDHs) and its calcined product (CZA-LDH). J. Inorg. Organomet. Polym. Mater. 28, 1127–1135 (2018).
Pasieczna-Patkowska, S. & Madej, J. Comparison of photoacoustic, diffuse reflectance, attenuated total reflectance and transmission infrared spectroscopy for the study of biochars. Polish J. Chem. Technology, 20(4). (2018).
Dehkhoda, A. M., Ellis, N. & Gyenge, E. Electrosorption on activated biochar: effect of thermo-chemical activation treatment on the electric double layer capacitance. J. Appl. Electrochem. 44, 141–157 (2014).
Tang, D. et al. Y Facile synthesis of magnetic ZnAl layered double hydroxides and efficient adsorption of malachite green and congo red. Sep. Purif. Technol. : 322, 124305. (2023).
Pathania, D. et al. Biochar supported Ag/Cu-ZrO2 nano-hetero assembly for enhanced adsorption of heavy metal ions and biomedical applications. Nanotechnol Environ. Eng. 2, 189–206 (2024).
Thakur, M., Kumar, A., Sharma, A. & Pathania, D. Synthesis of Potato-Starch based Bio-nanocomposite for the removal of Trifluralin under visible light illumination. CHEM. AFR. 4, 1981–1993 (2024).
Sharma, A., Thakur, M., Kumar, A., Pathania, D. & Sharma, A. Fabrication of xyloglucan-based zirconium (IV) selenophosphate nanostructure for removal of deflazacort and antimicrobial applications. SCENV 7, 100131 (2024).
Din, S. U. et al. Investigation on cadmium ions removal from water by a nanomagnetite based Biochar derived from Eleocharis dulcis. J. Inorg. Organomet. Polym. Mater. 31, 415–425 (2021).
Majamo, S. L., Amibo, T. A. & Bedru, T. K. Synthesis and application of biomass-derived magnetic Biochar catalyst for simultaneous esterification and trans-esterification of waste cooking oil into biodiesel: modeling and optimization. Mater. Renew. Sustain. Energy. 2, 147–158 (2023).
Barnabas, M. J., Parambadath, S., Nagappan, S. & Ha, C. S. Sulfamerazine Schiff-base complex intercalated layered double hydroxide: synthesis, characterization, and antimicrobial activity. Heliyon. 5 (4), (2019).
Fayad, E., Binjawhar, D. N., Elsaid, F. G., Taha, A. & Mubarak, M. F. Innovative CuZnCr-BTC framework for enhanced congo red dye removal in sustainable wastewater treatment. J. Cluster Sci. 36 (4), 125 (2025).
Kumari, P., Pal, B. & Das, R. K. Superior adsorptive removal of eco-toxic drug diclofenac sodium by Zn–Al LDH⋅ xBi2O3 layer double hydroxide composites. Appl. Clay Sci. 208, 106119 (2021).
Wu, K. et al. ZnAl-LDH/wood-based antifouling membranes for high-flux and efficient oil/water separation. J. Hazard. Mater. 490, 137739. (2025).
Rao, M. et al. Study on ultrasonic assisted intensive leaching of germanium from germanium concentrate using HCl/NaOCl. Hydrometallurgy 230, 106385 (2024).
Zhang, H. et al. Selective transformation and removal of as (III) by constructed Fe – N bonds: the generation of singlet oxygen from the photoexcitation of MnPc leads to abundant ZnFe – LDH interface OH radical. Sci. Total Environ. 890, 164314 (2023).
Rahman, S. et al. High capacity aqueous phosphate reclamation using Fe/Mg-layered double hydroxide (LDH) dispersed on Biochar. J. Colloid Interface Sci. 597, 182–195 (2021).
Zhu, Y. et al. Enhanced photocatalytic activity of Zn/Ti-LDH via hybridizing with C60. MOL. CATAL. 427, 54–61 (2017).
Li, X. et al. A novel strategy to construct a visible-light-driven Z-scheme (ZnAl-LDH with active phase/g-C3N4) heterojunction catalyst via polydopamine Bridge (a similar Bridge structure). J. Hazard. Mater. 386, 121650 (2020).
Zou, J. et al. Photocatalytic selective oxidation of benzyl alcohol over ZnTi-LDH: the effect of surface OH groups. Appl. Catal. B. 260, 118185 (2020).
Smith, M., Scudiero, L., Espinal, J., McEwen, J. S. & Garcia-Perez, M. Improving the Deconvolution and interpretation of XPS spectra from Chars by Ab initio calculations. Carbon 110, 155–171 (2016).
Peighambardoust, S. J., Abdollahian Aghbolagh, S., Foroutan, R. & Peighambardoust, N. S. Decontamination of crystal Violet using nanocomposite adsorbent based on pine cone Biochar modified with CoFe₂O₄/Mn-Fe LDH. Sci. Rep. 15 (1), 15067 (2025).
Wang, S., Gao, B., Li, Y., Zimmerman, A. R. & Cao, X. Sorption of arsenic onto Ni/Fe layered double hydroxide (LDH)-biochar composites. RSC Adv. 6 (22), 17792–17799 (2016).
Lee, S. H., Choi, H. & Kim, K. W. Removal of as (V) and Sb (V) in aqueous solution by Mg/Al-layered double hydroxide-incorporated polyethersulfone polymer beads (PES-LDH). Environ. Geochem. Health. 40, 2119–2129 (2018).
Kumari, S. et al. Strategic synthesis of biowaste-derived magnetic hydrochar for adsorption and photocatalytic removal of Chlorpyrifos herbicides from simulated wastewater. MSEB : 314,118009. (2025).
Gao, C. et al. Millimeter-sized Mg–Al-LDH nanoflake impregnated magnetic alginate beads (LDH-n-MABs): a novel bio-based sorbent for the removal of fluoride in water. J. Mater. Chem. A. 2 (7), 2119–2128 (2014).
Pu, S. et al. Isolation, identification, and characterization of an Aspergillus Niger bioflocculant-producing strain using potato starch wastewater as nutrilite and its application. PLoS ONE. 13 (1), e0190236 (2018).
Sharma, A., Siddiqi, Z. M. & Pathania, D. Adsorption of polyaromatic pollutants from water system using carbon/ZnFe2O4 nanocomposite: equilibrium, kinetic and thermodynamic mechanism. J. Mol. Liq. 240, 361–371 (2017).
Dharmapriya, T. N., Li, D., Chung, Y. C. & Huang, P. J. Green synthesis of reusable adsorbents for the removal of heavy metal ions. ACS Omega. 6 (45), 30478–30487 (2021).
Sharma, A., Sharma, G., Naushad, M., Ghfar, A. A. & Pathania, D. Remediation of anionic dye from aqueous system using bio-adsorbent prepared by microwave activation. Environ. Technol. 39 (7), 917–930 (2018).
Kumar, A., Pathania, D., Gupta, N., Raj, P. & Sharma, A. Photo-degradation of noxious pollutants from water system using cornulaca monacantha stem supported ZnFe2O4 magnetic bio-nanocomposite. Sustain. Chem. Pharm. 1, 18:100290 (2020).
Zubair, M., Daud, M., McKay, G., Shehzad, F. & Al-Harthi, M. A. Recent progress in layered double hydroxides (LDH)-containing hybrids as adsorbents for water remediation. Appl. Clay Sci. : 143, 79-292 (2017).
Das, S., Dash, S. K. & Parida, K. M. Kinetics, isotherm, and thermodynamic study for ultrafast adsorption of Azo dye by an efficient sorbent: ternary Mg/(Al + Fe) layered double hydroxides. ACS Omega. 3 (3), 2532–2545 (2018).
Su, L. et al. Creep characterisation and microstructural analysis of municipal solid waste incineration fly ash geopolymer backfill. Sci. Rep. 14 (1), 29828 (2024).
Çiftçi, T. D. & Henden, E. Nickel/nickel boride nanoparticles coated resin: A novel adsorbent for arsenic (III) and arsenic (V) removal. J Powder Technol. 269, 470 – 80 (2015).
65. Otgonjargal, E., Kim, Y. S., Park, S. M., Baek, K., Yang, J. S., Mn–Fe layered double hydroxides for adsorption of As (III) and As (V), Sep. Sci. Technol., 47, 2192–2198 (2012).66. Bessaies, H., et al., Synthesis of novel adsorbent by intercalation of biopolymer in LDH for the removal of arsenic from synthetic and natural water, Environ. Sci., 91, 246–261 (2020). 67. Ma, L., et al., Selective and efficient removal of toxic oxoanions of As (III), As (V), and Cr (VI) by layered double hydroxide intercalated with MoS4²⁻, J. Mater. Chem., 29, 3274–3284 (2017). 68. Guo, Q., et al., Effective treatment of arsenic-bearing water by a layered double metal hydroxide: Iowaite, J. Appl. Geochem., 77, 206–212 (2017). 69. Hong, J., Zhu, Z., Lu, H., Qiu, Y., Synthesis and arsenic adsorption performances of ferric- based layered double hydroxide with α-alanine intercalation, Chem. Eng. J., 252, 267–274 (2014). 70. Yavuz, C. T., et al., Low-field magnetic separation of monodisperse Fe3O4 nanocrystals, Science, 314, 964–967 (2006). 71. Zhang, G., Ren, Z., Zhang, X., Chen, J., Nanostructured iron (III)-copper (II) binary oxide: a novel adsorbent for enhanced arsenic removal from aqueous solutions, Water Res., 47, 4022–4031 (2013). 72. Chen, B., et al., Facile hydrothermal synthesis of nanostructured hollow iron–cerium alkoxides and their superior arsenic adsorption performance, ACS Appl. Mater. Interfaces, 6, 14016–14025 (2014). 73. Du, Y., et al., α-Fe2O3 nanowires deposited diatomite: highly efficient absorbents for the removal of arsenic, J. Mater. Chem. A, 1, 7729–7737 (2013). 74. Yang, J., et al., High-content, well-dispersed γ-Fe2O3 nanoparticles encapsulated in macroporous silica with superior arsenic removal performance, Adv. Funct. Mater., 24, 1354–1363 (2014). 75. Su, H., Ye, Z., Hmidi, N., Subramanian, R., Carbon nanosphere–iron oxide nanocomposites as high-capacity adsorbents for arsenic removal, RSC Adv., 7, 36138–36148 (2017)
Funding
The authors (Abdulrhman Alsayari and Shadma Wahab) extend their appreciation to the Deanship of Research and Graduate studies at King Khalid University for funding them through large group Research Project under grant number (RGP2/425/46). The authors also extend their appreciation to Maharishi Markandeshwar University (Deemed to be University), Mullana, Ambala for providing the laboratory and necessary instrumental support.
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Arush Sharma: Writing–review & editing, Writing–original draft, Software, Data curation. Suchi Sharma and Ajay Kumar: Formal analysis, Visualization. Nadeem Sharma and Abhishek Thakur: Investigation. Methodology, Investigation, Data curation. Anand Somvanshi, Rohit Jasrotia and Deepak Pathania: Supervision. Abdulrhman Alsayari and Shadma Wahab: Resources. Allah Dekama Jara: Writing-Review and Editing, Resources.
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Sharma, S., Sharma, N., Somvanshi, A. et al. Waste citrus pseudolimon peels derived biochar assisted magnetic Zn + Al (LDH) nanocomposites for As (III) adsorption. Sci Rep (2026). https://doi.org/10.1038/s41598-026-40288-x
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DOI: https://doi.org/10.1038/s41598-026-40288-x