Adsorptive Separation of Nitrate from Water Using Rice Dust Biochar: Performance at 5-10 ppm Concentration

Authors

  • Manoj Kumar Sepat Department of Chemistry, S.M.C.C. Govt. College, Aburoad (Raj.) - 307026, INDIA.
  • Hanumant Singh Department of Chemistry, S.M.C.C. Govt. College, Aburoad (Raj.) - 307026, INDIA.

DOI:

https://doi.org/10.55544/jrasb.5.3.19

Keywords:

nitrate removal, rice dust biochar, adsorption, low concentration, isotherm, kinetics

Abstract

Nitrate contamination of groundwater threatens public health, yet most adsorption studies are conducted at concentrations far above those found in many supplies. This study evaluated rice dust biochar (RDB), a low-cost residue-derived sorbent, for nitrate removal at 5-10 mg L-1. The biochar was produced by oxygen-limited pyrolysis at 500 °C and characterized by SEM-EDS, FTIR, BET, XRD and pHpzc analysis. Batch experiments examined pH, dose, contact time, initial concentration and temperature, and the data were interpreted with isotherm, kinetic and thermodynamic models. RDB was a mesoporous material (86.4 m2 g-1) with a pHpzc of 6.8. Removal peaked at pH 4 (83.4%), the optimum dose was 2.0 g L-1, and equilibrium was reached in about 90 min. Kinetics followed the pseudo-second-order model (R2 = 1.000), and the Freundlich isotherm gave the best fit (R2 = 0.999). Across 5-10 mg L-1, removal was 82.8-86.8%, and adsorption was spontaneous and endothermic, with evidence pointing to electrostatic attraction, anion exchange and pore filling. After five regeneration cycles, 88% of the initial efficiency was retained; phosphate was the most inhibitory coexisting anion, and removal in a real water sample was 74.0%. These findings indicate that RDB is a promising candidate for trace-level nitrate polishing, pending column and leaching studies.

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References

[1] Singh, B., & Sekhon, G. S. (1979). Nitrate pollution of groundwater from farm use of nitrogen fertilizers—A review. Journal of Hydrology, 42(3–4), 207–225. https://doi.org/10.1016/0022-1694(79)90022-5

[2] Rivett, M. O., Buss, S. R., Morgan, P., Smith, J. W. N., & Bemment, C. D. (2008). Nitrate attenuation in groundwater: A review of biogeochemical controlling processes. Water Research, 42(16), 4215–4232. https://doi.org/10.1016/j.watres.2008.07.020

[3] Ward, M. H., Jones, R. R., Brender, J. D., de Kok, T. M., Weyer, P. J., Nolan, B. T., Villanueva, C. M., & van Breda, S. G. (2018). Drinking water nitrate and human health: An updated review. International Journal of Environmental Research and Public Health, 15(7), Article 1557. https://doi.org/10.3390/ijerph15071557

[4] Greer, F. R., & Shannon, M. (2005). Infant methemoglobinemia: The role of dietary nitrate in food and water. Pediatrics, 116(3), 784–786. https://doi.org/10.1542/peds.2005-1497

[5] International Agency for Research on Cancer. (2010). Ingested nitrate and nitrite, and cyanobacterial peptide toxins. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 94. https://publications.iarc.who.int/112

[6] Camargo, J. A., & Alonso, Á. (2006). Ecological and toxicological effects of inorganic nitrogen pollution in aquatic ecosystems: A global assessment. Environment International, 32(6), 831–849. https://doi.org/10.1016/j.envint.2006.05.002

[7] World Health Organization. (2017). Guidelines for drinking-water quality: Fourth edition incorporating the first addendum. https://www.who.int/publications/i/item/9789241549950

[8] Bureau of Indian Standards. (2012). IS 10500: Drinking water—Specification.

[9] Kapoor, A., & Viraraghavan, T. (1997). Nitrate removal from drinking water—Review. Journal of Environmental Engineering, 123(4), 371–380. https://doi.org/10.1061/(ASCE)0733-9372(1997)123:4(371)

[10] Bhatnagar, A., & Sillanpää, M. (2011). A review of emerging adsorbents for nitrate removal from water. Chemical Engineering Journal, 168(2), 493–504. https://doi.org/10.1016/j.cej.2011.01.103

[11] Soares, M. I. M. (2000). Biological denitrification of groundwater. Water, Air, and Soil Pollution, 123, 183–193.

[12] Priya, E., Kumar, S., Verma, C., Sarkar, S., & Maji, P. K. (2022). A comprehensive review on technological advances of adsorption for removing nitrate and phosphate from waste water. Journal of Water Process Engineering, 49, Article 103159. https://doi.org/10.1016/j.jwpe.2022.103159

[13] Lehmann, J., & Joseph, S. (Eds.). (2015). Biochar for environmental management: Science, technology and implementation (2nd ed.). Routledge.

[14] Ahmad, M., Rajapaksha, A. U., Lim, J. E., Zhang, M., Bolan, N., Mohan, D., Vithanage, M., Lee, S. S., & Ok, Y. S. (2014). Biochar as a sorbent for contaminant management in soil and water: A review. Chemosphere, 99, 19–33. https://doi.org/10.1016/j.chemosphere.2013.10.071

[15] Phuong, N. D., Phuong, D. T. M., Chiem, N. H., Thoa, P. N., & Loc, N. X. (2021). Adsorption of nitrate by biochar prepared from rice husks (O. sativa L., OM5451). Hue University Journal of Science: Natural Sciences, 130(1A), 31–39. https://doi.org/10.26459/hueunijns.v130i1A.5957

[16] Mohan, D., Sarswat, A., Ok, Y. S., & Pittman, C. U., Jr. (2014). Organic and inorganic contaminants removal from water with biochar, a renewable, low cost and sustainable adsorbent—A critical review. Bioresource Technology, 160, 191–202. https://doi.org/10.1016/j.biortech.2014.01.120

[17] Inyang, M. I., Gao, B., Yao, Y., Xue, Y., Zimmerman, A., Mosa, A., Pullammanappallil, P., Ok, Y. S., & Cao, X. (2016). A review of biochar as a low-cost adsorbent for aqueous heavy metal removal. Critical Reviews in Environmental Science and Technology, 46(4), 406–433. https://doi.org/10.1080/10643389.2015.1096880

[18] Lugo-Arias, J., González-Álvarez, J., & Maturana, A. (2026). Mg-impregnated rice husk biochar in fixed-bed columns: High-capacity continuous-flow removal of nitrate and phosphate from wastewater. Biomass Conversion and Biorefinery, 16, Article 149. https://doi.org/10.1007/s13399-026-07093-y

[19] Huno, S. K. M., Das, J., van Hullebusch, E. D., Annachhatre, A. P., & Rene, E. R. (2023). Nitrate removal from groundwater using chemically modified coconut husk based granular activated carbon: Characterization of the adsorbent, kinetics and mechanism. Systems Microbiology and Biomanufacturing, 3(2), 370–383. https://doi.org/10.1007/s43393-022-00108-5

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Published

2026-06-30

How to Cite

Sepat, M. K., & Singh, H. (2026). Adsorptive Separation of Nitrate from Water Using Rice Dust Biochar: Performance at 5-10 ppm Concentration. Journal for Research in Applied Sciences and Biotechnology, 5(3), 130–139. https://doi.org/10.55544/jrasb.5.3.19

Issue

Vol. 5 No. 3 (2026): June Issue

Section

Articles

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Copyright (c) 2026 Manoj Kumar Sepat, Hanumant Singh

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This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

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