Applied Chemical Engineering

Eco-friendly iron removal from contaminated water using chemically modified rice straw: Adsorption mechanisms and performance

Nur Qudus

Department of Civil Engineering, Faculty of Engineering, Universitas Negeri Semarang, Kampus Sekaran Gunungpati, Semarang 50229, Indonesia

Harianingsih

Department of Chemical Engineering, Faculty of Engineering, Universitas Negeri Semarang, Kampus Sekaran Gunungpati, Semarang 50229, Indonesia

Virgiawan Adi Kristianto

Department of Civil Engineering, Faculty of Engineering, Universitas Negeri Semarang, Kampus Sekaran Gunungpati, Semarang 50229, Indonesia

Dimas Gustoro

Department of Civil Engineering, Faculty of Engineering, Universitas Negeri Semarang, Kampus Sekaran Gunungpati, Semarang 50229, Indonesia

Muhammad Arief Kariem

Department of Chemical Engineering, Faculty of Engineering, Universitas Muhammadiyah Palembang, Talang Banteng Street 13, Ulu Palembang, Indonesia

Indra Sakti Pangestu

Department of Chemical Engineering, Faculty of Engineering, Universitas Negeri Semarang, Kampus Sekaran Gunungpati, Semarang 50229, Indonesia

Rizky Ilham Fadzillah

Department of Chemical Engineering, Faculty of Engineering, Universitas Negeri Semarang, Kampus Sekaran Gunungpati, Semarang 50229, Indonesia

DOI: https://doi.org/10.59429/ace.v8i3.5637

Keywords: adsorption mechanism; agricultural waste; contaminated water; iron removal; rice straw

---

Abstract

The availability of water does not always guarantee its quality, particularly when it is contaminated with iron (Fe), which poses health risks such as kidney failure, cardiovascular diseases, and digestive disorders. This study evaluates the potential of rice straw -modified Ca(OH)₂ (Rs-OCa) as an adsorbent for removing Fe(II) ions from groundwater. Rice straw, a widely available agricultural waste in Indonesia, was chemically modified to enhance its adsorption capacity by increasing active sites, removing lignin, and improving its affinity for metal ions. FTIR analysis confirmed the presence of hydroxyl (-OH) and carboxyl (-COOH) functional groups, while XRD analysis revealed both crystalline and amorphous structures that contribute to stability and adsorption efficiency. Adsorption tests indicated optimal Fe(II) removal at pH 4–5 with an adsorbent dose of 0.75 g per 100 mL of solution. The adsorption isotherm followed the Langmuir model, with a maximum adsorption capacity (Qₘ) of 22.47 mg/g, indicating a homogeneous monolayer adsorption mechanism. The Freundlich model (KF = 8.91 mg/g, n = 2.5) further confirmed surface heterogeneity and high adsorption efficiency at low Fe (II) concentrations.The results demonstrate that Rs-OCa is an effective, economical, and environmentally friendly adsorbent for iron removal from contaminated water.

---

References

[1]. Xu F, Li P. Biogeochemical mechanisms of iron (Fe) and manganese (Mn) in groundwater and soil profiles in the Zhongning section of the Weining Plain (northwest China). Science of The Total Environment 2024; 173506. https://doi.org/10.1016/j.scitotenv.2024.173506.

[2]. Lee WS, Aziz HA, Akbar NA, Wang MHS, Wang LK. Removal of Fe and Mn from groundwater. In: Industrial Waste Engineering. Cham: Springer International Publishing 2024; 135-170. https://doi.org/10.1007/978-3-031-46747-912.

[3]. Zhang R, Leiviskä T, Tanskanen J, Gao B, Yue Q. Utilization of ferric groundwater treatment residuals for inorganic-organic hybrid biosorbent preparation and its use for vanadium removal. Chemical Engineering Journal 2019; 361: 680-689. https://doi.org/10.1016/j.cej.2018.12.122.

[4]. Zhang YU, Yang MIN, Dou XM, He H, Wang DS. Arsenate adsorption on an Fe−Ce bimetal oxide adsorbent: role of surface properties. Environmental Science & Technology 2005; 39(18): 7246-7253. https://doi.org/10.1021/es050775d.

[5]. Bhatnagar A, Sillanpää M. Removal of natural organic matter (NOM) and its constituents from water by adsorption–a review. Chemosphere 2017; 166: 497-510. https://doi.org/10.1016/j.chemosphere.2016.09.098.

[6]. Ewis D, Ba-Abbad MM, Benamor A, El-Naas MH. Adsorption of organic water pollutants by clays and clay minerals composites: A comprehensive review. Applied Clay Science 2022; 229: 106686. https://doi.org/10.1016/j.clay.2022.106686.

[7]. Swaren L, Safari S, Konhauser KO, Alessi DS. Pyrolyzed biomass-derived nanoparticles: a review of surface chemistry, contaminant mobility, and future research avenues to fill the gaps. Biochar 2022; 4(1): 33. doi: (if available). https://doi.org/10.1007/s42773-022-00152-3.

[8]. Bayuo J, Rwiza M, Mtei K. A comprehensive review on the decontamination of lead (II) from water and wastewater by low-cost biosorbents. RSC advances 2022; 12(18): 11233-11254. https://doi.org/10.1039/d2ra00796g.

[9]. Salem LR. Kinetics and adsorption isotherm of strontium on sugarcane biochar and its application in polluted soil. International Journal of Environmental Research 2023; 17(3): 42. https://doi.org/10.1007/s41742-023-00532-y.

[10]. Siswoyo E, Dai Y, Mori M, Wada N, Itabashi H. Environmentally Friendly Adsorbents. In: Design of Materials and Technologies for Environmental Remediation. Singapore: Springer Nature Singapore 2022; 293-333. https://doi.org/10.1007/698_2021_827.

[11]. Bambal A, Gomase V, Saravanan D, Jugade R. Highly efficient mesoporous aluminium-magnetite-alginate magnetic composite for defluoridation of water. Environmental Research 2024; 261: 119698. https://doi.org/10.1016/j.envres.2024.119698.

[12]. Zhang T, Payne K, Zhang J, Purswani P, Karpyn Z, Wang M. Hybrid ion exchange and biological processes for water and wastewater treatment: a comprehensive review of process applications and mathematical modeling. Reviews in Environmental Science and Bio/Technology 2024; 23(1): 163-188. https://doi.org/10.1007/s11157-023-09677-w.

[13]. Bhatia D, Saroha AK. Use of Iron-Modified Biochar Obtained from Rice Straw as an Adsorbent for Removal of Arsenic from Water. Journal of Hazardous, Toxic, and Radioactive Waste 2024; 28(3): 04024010. https://doi.org/10.1061/jhtrbp.hzeng-1304.

[14]. Khan BA, Ahmad M, Bolan N, Farooqi A, Iqbal S, Mickan B, et al. A mechanistic approach to arsenic adsorption and immobilization in aqueous solution, groundwater, and contaminated paddy soil using pine-cone magnetic biochar. Environmental Research 2024; 245: 117922. https://doi.org/10.1016/j.envres.2023.117922.

[15]. Akbari Zadeh M, Daghbandan A, Abbasi Souraki B. Removal of iron and manganese from groundwater sources using nano-biosorbents. Chemical and Biological Technologies in Agriculture 2022; 9: 1-14. https://doi.org/10.1186/s40538-021-00268-x.

[16]. Singh S, Saksham, Kaith BS, Kumar R, Bajwa BS, Kaur I. Nanocellulose extracted from wheat straw: facile synthesis, characterization and application as an efficient U (VI) scavenger for groundwater of Bathinda district, SW-Punjab. Journal of Radioanalytical and Nuclear Chemistry 2024; 333(6): 3229-3238. https://doi.org/10.1007/s10967-023-09314-4.

[17]. Senapati S, Giri J, Mallick L, Biswal P, Mohapatra S, Behera D, et al. Ultra-fast adsorption of the industrial cationic dye pollutant using nitric acid-activated rice straw biochar: insights into adsorption mechanisms. Biomass Conversion and Biorefinery 2025; 1-19. https://doi.org/10.1007/s13399-025-06540-6.

[18]. Dakhem M, Ghanati F, Afshar Mohammadian M, Sharifi M. Effective biosorption of Al ions from drinking water by lignocellulosic biomass rice straw. International Journal of Phytoremediation 2024; 26(7): 1087-1098. https://doi.org/10.1080/15226514.2023.2289588.

[19]. Smolyanichenko A. Physical and chemical properties of silver-containing nanosorbent obtained from rice straw biochar. Agriculture 2023; 13(7): 1288. https://doi.org/10.3390/agriculture13071288.

[20]. Hamid Y, Chen Y, Lin Q, Haris M, Usman M, Rashid MS, et al. Functionality of wheat straw-derived biochar enhanced its efficiency for actively capping Cd and Pb in contaminated water and soil matrices: Insights through batch adsorption and flow-through experiments. Chemosphere 2024; 362: 142770. https://doi.org/10.1016/j.chemosphere.2024.142770.

[21]. Nguyen TH, Pham TH, Nguyen Thi HT, Nguyen TN, Nguyen MV, Tran Dinh T, et al. Synthesis of Iron‐Modified Biochar Derived from Rice Straw and Its Application to Arsenic Removal. Journal of Chemistry 2019; 2019(1): 5295610. https://doi.org/10.1155/2019/5295610.

[22]. Umare S, Thawait AK, Dhawane SH. Remediation of arsenic and fluoride from groundwater: a critical review on bioadsorption, mechanism, future application, and challenges for water purification. Environmental Science and Pollution Research 2024; 1-30. https://doi.org/10.1007/s11356-024-33679-y.

[23]. Huang H, Ge L, Zhang X, Chen H, Shen Y, Xiao J, et al. Rice straw biochar and lime regulate the availability of heavy metals by managing colloid-associated-but dissolved-heavy metals. Chemosphere 2024; 349: 140813. https://doi.org/10.1016/j.chemosphere.2023.140813.

[24]. Darma A, Liu Y, Xia X, Wang Y, Jin L, Yang J. Arsenic (III) sorption on organo-ferrihydrite coprecipitates: Insights from maize and rape straw-derived DOM. Chemosphere 2024; 352: 141372. https://doi.org/10.1016/j.chemosphere.2024.141372.

[25]. Robles-Jimarez HR, Sanjuan-Navarro L, Jornet-Martínez N, Primaz CT, Teruel-Juanes R, Molins-Legua C, et al. New silica based adsorbent material from rice straw and its in-flow application to nitrate reduction in waters: Process sustainability and scale-up possibilities. Science of the Total Environment 2022; 805: 150317. https://doi.org/10.1016/j.scitotenv.2021.150317.

[26]. Robles-Jimarez HR, Sanjuan-Navarro L, Jornet-Martínez N, Primaz CT, Teruel-Juanes R, Molins-Legua C, et al. New silica based adsorbent material from rice straw and its in-flow application to nitrate reduction in waters: Process sustainability and scale-up possibilities. Science of the Total Environment 2022; 805: 150317. https://doi.org/10.1016/j.scitotenv.2021.150317.

[27]. Ha TTV, Viet NM, Quan VT, Huong NTL. Novel Fe3O4-modified biochar generated from rice husk: a sustainable strategy for strengthening lead absorption in wastewater. International Journal of Environmental Science and Technology 2024; 1-10. https://doi.org/10.1007/s13762-024-05626-4.

[28]. Haris M, Amjad Z, Usman M, Saleem A, Dyussenova A, Mahmood Z, et al. A review of crop residue-based biochar as an efficient adsorbent to remove trace elements from aquatic systems. Biochar 2024; 6(1): 47. https://doi.org/10.1007/s42773-024-00341-2.

[29]. Rani M, Keshu, Shanker U. Green synthesis of sunlight active rice husk biochar loaded with metal ferrite nanocomposite for efficient removal of pesticides: kinetics and photoactivity. Biomass Conversion and Biorefinery 2024; 1-15. https://doi.org/10.1007/s13399-024-06000-7.

[30]. Abed EA, Alaboudi KA, Abbas MH, Attia TM, Abdelhafez AA. Iron Contamination in Groundwater: Risk Assessment and Remediation Techniques in Egypt’s New Valley. Water 2024; 16(13): 1834. https://doi.org/10.3390/w16131834.

[31]. Chatzimichailidou S, Xanthopoulou M, Tolkou AK, Katsoyiannis IA. Biochar derived from rice by-products for arsenic and chromium removal by adsorption: a review. Journal of Composites Science 2023; 7(2): 59. https://doi.org/10.3390/jcs7020059.

[32]. Pap S, Sekulic MT, Tran HN, Chao HP, Gilbert PJ, Gibb SW, et al. Comparison of two carbonaceous supported Fe-rich adsorbents for arsenate removal: A functionalisation and mechanistic study with applicability to groundwater treatment. Chemosphere 2024; 359: 142205. https://doi.org/10.1016/j.chemosphere.2024.142205.

[33]. Liang T, Zhou G, Chang D, Ma Z, Gao S, Nie J, et al. The dissolved organic matter from the co-decomposition of Chinese milk vetch and rice straw induces the strengthening of Cd remediation by Fe-modified biochar. Biochar 2024; 6(1): 27. https://doi.org/10.1007/s42773-024-00313-6.

[34]. Lee WS, Aziz HA, Akbar NA, Wang MHS, Wang LK. Removal of Fe and Mn from groundwater. In: Industrial Waste Engineering. Cham: Springer International Publishing 2024; 135-170. https://doi.org/10.1007/978-3-031-46747-9_4.

[35]. Mohiuddin I, Singh R, Kaur V. Blending polydopamine-derived imprinted polymers with rice straw-based fluorescent carbon dots for selective detection and adsorptive removal of ibuprofen. International Journal of Biological Macromolecules 2024; 269: 131765. https://doi.org/10.1016/j.ijbiomac.2024.131765.

[36]. Dakhem M, Ghanati F, Afshar Mohammadian M, Sharifi M. Effective biosorption of Al ions from drinking water by lignocellulosic biomass rice straw. International Journal of Phytoremediation 2024; 26(7): 1087-1098. https://doi.org/10.1080/15226514.2023.2289588.

[37]. Sakhiya AK, Vijay VK, Kaushal P. Development of rice straw biochar through pyrolysis to improve drinking water quality in arsenic and manganese contaminated areas. Surfaces and Interfaces 2023; 36: 102582. https://doi.org/10.1016/j.surfin.2022.102582.

[38]. Ning K, Chen H, Wang D, Hu Y, He Y, Hao S, et al. Effective removal of fluoride and lead ions from aqueous solutions using water treatment residue and rice straw co-pyrolysis biochar composites. Environmental Technology & Innovation 2024; 34: 103589. https://doi.org/10.1016/j.eti.2024.103589.

[39]. Umare S, Thawait AK, Dhawane SH. Remediation of arsenic and fluoride from groundwater: a critical review on bioadsorption, mechanism, future application, and challenges for water purification. Environmental Science and Pollution Research 2024; 1-30. https://doi.org/10.1007/s11356-024-33679-y.

[40]. Cuong VT, Nguyen TH, Do TX, Vu AT. Preparation of novel CS/SiO2-EDTA nanocomposite from ash of rice straw pellets for enhanced removal efficiency of heavy metal ions in aqueous medium. Journal of Water Process Engineering 2024; 60: 105175. https://doi.org/10.1016/j.jwpe.2024.105175.

[41]. Ahmad S, Gautam SB, Sawood GM, Dixit S, Mishra A. Modified paddy husk carbon with linked fibrils of FeHO2 using aluminium as the surface regulator for enhanced As (III) removal in fixed bed system. International Journal of Chemical Reactor Engineering 2024; 22(2): 153-170. https://doi.org/10.21203/rs.3.rs-3028579/v1.

[42]. Chowdhury MF, Khanum MUKH, Rahman MA, Rahman MM, Kabir SF, Rahaman MH, et al. Dynamic intercalation of methylene blue in BC-MgFe-HT composite: Unveiling adsorption mechanisms for efficient wastewater treatment. Groundwater for Sustainable Development 2024; 27: 101314. https://doi.org/10.1016/j.gsd.2024.101314.