EG/
Articles/
2608005023
  • Open Access
  • Article

Effective Removal of Malachite Green Dye on Camellia Sinensis Ash

  • Santosh Kumar 1,†,   
  • Nidhi Rai 1,2,†,   
  • Sanju Soni 1,   
  • Sonu Kumar 1,   
  • Aazad Verma 1,   
  • Charu Arora 1,*

Received: 04 Jul 2026 | Revised: 09 Aug 2026 | Accepted: 25 Aug 2026 | Published: 07 Sep 2026

Abstract

This study investigates the efficacy of Camellia sinensis ash (tea powder/waste ash) as an adsorbent for removing Malachite Green (MG) dye from aqueous solutions. Comprehensive analyses, including SEM, XRD, BET surface area, and FTIR, were conducted to characterise the adsorbent. Key parameters influencing adsorption, such as pH, temperature, initial dye concentration, contact time, and adsorbent dosage, were systematically evaluated. Results indicated that at 30 °C, tea ash removed approximately 95.87% of MG dye from a 25 mg/L solution, with optimal performance observed in alkaline conditions. Column experiments revealed a maximum adsorption capacity of 75.02 mg/g. The Temkin isotherm model best described the adsorption equilibrium with a high correlation coefficient of 0.95. Thermodynamic analysis indicated an endothermic, spontaneous process; kinetic data best fit the pseudo-first-order model, consistent with physisorption.

References 

  • 1.

    Hussain, S.; Salman, M.; Youngblood, J.P.; et al. Enhanced Adsorption of Congo Red Dye by CS/PEG/ZnO Composite Hydrogel: Synthesis, Characterization, and Performance Evaluation. J. Mol. Liq. 2024, 411, 125704. https://doi.org/10.1016/j.molliq.2024.125704.

  • 2.

    Dubey, S.K.; Yadav, R.; Chaturvedi, R.K.; et al. Contamination of Ground Water as a Consequence of Land Disposal of Dye Waste Mixed Sewage Effluents: A Case Study of Panipat District of Haryana, India. Bull. Environ. Contam. Toxicol. 2010, 85, 295–300. https://doi.org/10.1007/s00128-010-0073-2.

  • 3.

    Soni, S.; Rai, N.; Bajpai, P.K.; et al. Enhanced Sequestration of an Acidic Dye on Novel Bimetallic Metal-Organic Framework. J. Dispers. Sci. Technol. 2022, 45, 107–116. https://doi.org/10.1080/01932691.2022.2135521.

  • 4.

    Tkaczyk, A.; Mitrowska, K.; Posyniak, A. Synthetic Organic Dyes as Contaminants of the Aquatic Environment and Their Implications for Ecosystems: A Review. Sci. Total Environ. 2020, 717, 137222. https://doi.org/10.1016/j.scitotenv.2020.137222.

  • 5.

    Pillay, T.V.R. Aquaculture and the Environment; Fishing News Books: Oxford, UK, 1992; pp. 235–244.

  • 6.

    Arora, C.; Kumar, P.; Soni, S.; et al. Efficient Removal of Malachite Green Dye from Aqueous Solution Using Curcuma caesia Based Activated Carbon. Desalination Water Treat. 2020, 195, 341–352. https://doi.org/10.5004/dwt.2020.25897.

  • 7.

    Sirach, R.; Dave, P.N. Glutaraldehyde crosslinked chitosan-β-cyclodextrin/ZnO composite for the effective adsorption of Congo red anionic dye: A glimpse into adsorption performance and ANN modeling. Carbohydr. Polym. Technol. Appl. 2025, 10, 100835.

  • 8.

    Méndez, A.; Barriga, S.; Saa, A.; et al. Removal of malachite green by adsorbents from paper industry waste materials. J. Therm. Anal. Calorim. 2010, 99, 993–998. https://doi.org/10.1007/s10973-010-0681-4.

  • 9.

    Srivastava, S.; Sinha, R.; Roy, D. Toxicological Effects of Malachite Green. Aquat. Toxicol. 2004, 66, 319–329. https://doi.org/10.1016/j.aquatox.2003.09.008.

  • 10.

    Fessard, V.; Godard, T.; Huet, S.; et al. Mutagenicity of Malachite Green and Leucomalachite Green in in Vitro Tests. J. Appl. Toxicol. 1999, 19, 421–430. https://doi.org/10.1002/(sici)1099-1263(199911/12)19:6<421::aid-jat595>3.0.co;2-6.

  • 11.

    Gerundo, N.; Alderman, D.J.; Clifton-Hadley, R.S.; et al. Pathological effects of repeated doses of malachite green: a preliminary study. J. Fish Dis. 1991, 14, 521–532. https://doi.org/10.1111/j.1365-2761.1991.tb00607.x.

  • 12.

    Mittelstaedt, R.A.; Mei, N.; Webb, P.J.; et al. Genotoxicity of Malachite Green and Leucomalachite Green in Female Big Blue B6C3F1 Mice. Mutat. Res. Genet. Toxicol. Env. Mutagen. 2004, 561, 127–138. https://doi.org/10.1016/j.mrgentox.2004.04.003.

  • 13.

    Arora, C.; Sahu, D.; Bharti, D.; et al. Adsorption of hazardous dye crystal violet from industrial waste using low-cost adsorbent Chenopodium album. Desalination Water Treat. 2019, 167, 324–332. https://doi.org/10.5004/dwt.2019.24595.

  • 14.

    Cevallos-Mendoza, J.; Amorim, C.G.; Rodríguez-Díaz, J.M.; et al. Removal of Contaminants from Water by Membrane Filtration: A Review. Membranes 2022, 12, 570. https://doi.org/10.3390/membranes12060570.

  • 15.

    Yang, H.; Zhang, G.; Chen, X.; et al. Quaternized fenugreek gum grafted poly(acrylamide-co-methacryloxyethyltrimethyl ammonium chloride) novel composite hydrogel for efficient removal of Congo red dye. Int. J. Biol. Macromol. 2025, 320, 146090. https://doi.org/10.1016/j.ijbiomac.2025.146090.

  • 16.

    Singh, A.; Pal, D.B.; Mohammad, A.; et al. Biological remediation technologies for dyes and heavy metals in wastewater treatment: New insight. Bioresour. Technol. 2022, 343, 126154. https://doi.org/10.1016/j.biortech.2021.126154.

  • 17.

    Parmar, N.; Rawat, M.; Kumar, J.V. Camellia sinensis (Green Tea): A Review. Glob. J. Pharmacol. 2012, 6, 52–59.

  • 18.

    Jabeen, H.; Shaukat, S.; Abd Ur Rahman, H.M. Deep eutectic solvent mediated synthesis of ZnO nanoparticles and their catalytic activity for the removal of hazardous organic dyes. J. Mol. Liq. 2024, 395, 123783.

  • 19.

    Awasthi, N.; Singh, A.K.; Jain, R.K.; et al. Degradation and detoxification of endosulfan isomers by a defined co-culture of two Bacillus strains. Appl. Microbiol. Biotechnol. 2003, 62, 279–283. https://doi.org/10.1007/s00253-003-1241-7.

  • 20.

    Debnath, B.; Haldar, D.; Purkait, M.K. Environmental Remediation by Tea Waste and Its Derivative Products: A Review on Present Status and Technological Advancements. Chemosphere 2022, 300, 134480. https://doi.org/10.1016/j.chemosphere.2022.134480.

  • 21.

    Jia, J.; Cai, M.; Li, X.; et al. Performance and mechanism of chitosan-modified La-based MOF nanocomposites for high-efficiency adsorption of azo anion dye Congo red. J. Ind. Eng. Chem. 2025, 143, 740–751

  • 22.

    Nasar, A. Utilization of Tea Wastes for the Removal of Toxic Dyes from Polluted Water: A Review. Biomass Convers. Biorefinery 2023, 13, 1399–1415. https://doi.org/10.1007/s13399-020-01205-y.

  • 23.

    Shah, S.K.; Pate, V.A. Tea Production in India: Challenges and Opportunities. J. Tea Sci. Res. 2016, 6, 1–6. https://doi.org/10.5376/jtsr.2016.06.0005.

  • 24.

    Guo, S.; Kumar Awasthi, M.; Wang, Y.; et al. Current Understanding in Conversion and Application of Tea Waste Biomass: A Review. Bioresour. Technol. 2021, 338, 125530. https://doi.org/10.1016/j.biortech.2021.125530.

  • 25.

    Hussain, S.; Salman, M.; Al-Ahmary, K.M.; et al. Synthesis of Potential Adsorbent for Removal of Malachite Green Dye Using Alginate Hydrogel Nanocomposites. Int. J. Biol. Macromol. 2025, 289, 138816. https://doi.org/10.1016/j.ijbiomac.2024.138816.

  • 26.

    Pal, I.; Chopra, L.; Rajendran, S.; et al. Novel synthesis of GG-g-PAN based hydrolyzed products exclusion of Congo red and methylene blue dyes undertaken aqueous medium for spectroscopic investigations. J. Mol. Liq. 2024, 416, 126346.

  • 27.

    Farasati Far, B.; Naimi-Jamal, M.R.; Jahanbakhshi, M.; et al. Decontamination of Congo red dye from aqueous solution using nanoclay/chitosan-graft-gelatin nanocomposite hydrogel. J. Mol. Liq. 2024, 395, 123839. https://doi.org/10.1016/j.molliq.2023.123839.

  • 28.

    Hussain, S.; Anjali, K.P.; Hassan, S.T.; et al. Waste Tea as a Novel Adsorbent: A Review. Appl. Water Sci. 2018, 8, 165. https://doi.org/10.1007/s13201-018-0824-5.

  • 29.

    Rasilingwani, T.E.; Gumbo, J.R.; Masindi, V.; et al. Removal of Congo red dye from industrial effluents using metal oxide-clay nanocomposites: Insight into adsorption and precipitation mechanisms. Water Resour. Ind. 2024, 31, 100253.

  • 30.

    Kushwaha, A.K.; Gupta, N.; Chattopadhyaya, M.C. Removal of cationic methylene blue and malachite green dyes from aqueous solution by waste materials of Daucus carota. J. Saudi Chem. Soc. 2014, 18, 200–207. https://doi.org/10.1016/j.jscs.2011.06.011.

  • 31.

    Mittal, A.; Mittal, J.; Malviya, A.; et al. Adsorption of Hazardous Dye Crystal Violet from Wastewater by Waste Materials. J. Colloid Interface Sci. 2010, 343, 463–473. https://doi.org/10.1016/j.jcis.2009.11.060.

  • 32.

    Osmari, T.A.; Gallon, R.; Schwaab, M.; et al. Statistical Analysis of Linear and Non-Linear Regression for the Estimation of Adsorption Isotherm Parameters. Adsorpt. Sci. Technol. 2013, 31, 433–458. https://doi.org/10.1260/0263-6174.31.5.433.

  • 33.

    Soni, S.; Bajpai, P.K.; Mittal, J.; et al. Utilisation of Cobalt Doped Iron Based MOF for Enhanced Removal and Recovery of Methylene Blue Dye from Waste Water. J. Mol. Liq. 2020, 314, 113642. https://doi.org/10.1016/j.molliq.2020.113642.

  • 34.

    Soni, S.; Bajpai, P.K.; Bharti, D.; et al. Removal of Crystal Violet from Aqueous Solution Using Iron Based Metal Organic Framework. Desalination Water Treat. 2020, 205, 386–399. https://doi.org/10.5004/dwt.2020.26387.

  • 35.

    Rai, N.; Sinha, D.K.; Soni, S.; et al. Biosorption study of basic dye using aerial part of widely growing weed Chenopodium album. Desalination Water Treat. 2023, 314, 276–285. https://doi.org/10.5004/dwt.2023.30112.

  • 36.

    Delpiano, G.R.; Tocco, D.; Medda, L.; et al. Adsorption of Malachite Green and Alizarin Red S Dyes Using Fe-BTC Metal Organic Framework as Adsorbent. Int. J. Mol. Sci. 2021, 22, 788. https://doi.org/10.3390/ijms22020788.

  • 37.

    Svidrytski, A.; Hlushkou, D.; Thommes, M.; et al. Modeling the Impact of Mesoporous Silica Microstructures on the Adsorption Hysteresis Loop. J. Phys. Chem. C 2020, 124, 21646–21655. https://doi.org/10.1021/acs.jpcc.0c07571.

  • 38.

    Patel, A.; Soni, S.; Mittal, J.; et al. Sequestration of Crystal Violet from Aqueous Solution Using Ash of Black Turmeric Rhizome. Desalination Water Treat. 2021, 220, 342–352. https://doi.org/10.5004/dwt.2021.26911.

  • 39.

    Tahir, S.S.; Rauf, N. Removal of Cationic Dye from Aqueous Solutions by Adsorption onto Bentonite Clay. Chemosphere 2006, 63, 1842–1848. https://doi.org/10.1016/j.chemosphere.2005.10.033.

  • 40.

    Hameed, B.H.; Ahmad, A.A. Batch Adsorption of Methylene Blue from Aqueous Solution by Garlic Peel, an Agricultural Waste Biomass. J. Hazard. Mater. 2009, 164, 870–875. https://doi.org/10.1016/j.jhazmat.2008.08.084.

  • 41.

    Mansour, M.S.; Ossman, M.E.; Farag, H.A. Removal of Cadmium(II) Ion from Wastewater by Adsorption onto Polyaniline Coated on Sawdust. Desalination 2011, 272, 301–305. https://doi.org/10.1016/j.desal.2011.01.037.

  • 42.

    Duff, D.G.; Ross, S.M.C.; Vaughan, D.H. Adsorption from Solution: An Experiment to Illustrate the Langmuir Adsorption Isotherm. J. Chem. Educ. 1988, 65, 815. https://doi.org/10.1021/ed065p815.

  • 43.

    Rai, N.; Verma, A.; Kumar, S.; et al. Affordable Sequestration of Basic Fuchsin Using Ferrocene Impregnated Iron-Based Metal-Organic Frameworks. Part. Sci. Technol. 2026, 44, 95–110. https://doi.org/10.1080/02726351.2025.2567434.

  • 44.

    Rai, N.; Soni, S.; Verma, A.; et al. Sequestration of a Cationic Dye Using Graphene Oxide as Adsorbent. Desalination Water Treat. 2023, 307, 180–189. https://doi.org/10.5004/dwt.2023.29846.

  • 45.

    Senthil Kumar, P.; Palaniyappan, M.; Priyadharshini, M.; et al. Adsorption of Basic Dye onto Raw and Surface-Modified Agricultural Waste. Environ. Prog. Sustain. Energy 2014, 33, 87–98. https://doi.org/10.1002/ep.11756.

  • 46.

    Zhao, X.; Liu, S.; Tang, Z.; et al. Synthesis of Magnetic Metal-Organic Framework (MOF) for Efficient Removal of Organic Dyes from Water. Sci. Rep. 2015, 5, 11849. https://doi.org/10.1038/srep11849.

  • 47.

    Khan, F.A.; Dar, B.A.; Farooqui, M. Characterization and adsorption of malachite green dye from aqueous solution onto Salix alba L. (Willow tree) leaves powder and its respective biochar. Int. J. Phytoremediation 2023, 25, 646–657. https://doi.org/10.1080/15226514.2022.2098909.

  • 48.

    Jabar, J.M.; Odusote, Y.A. Utilization of prepared activated biochar from water lily (Nymphaea lotus) stem for adsorption of malachite green dye from aqueous solution. Biomass Convers. Biorefinery2024, 14, 5999–6010. https://doi.org/10.1007/s13399-021-01399-9.

  • 49.

    Hammud, H.H.; Hammoud, M.H.; Hussein, A.A.; et al. Removal of Malachite Green Using Hydrochar from PALM Leaves. Sustainability 2023, 15, 8939. https://doi.org/10.3390/su15118939.

  • 50.

    Arora, C.; Verma, A.; Soni, S.; et al. Recent Advances in Sequestration of Dyes Using Metal-Organic Frameworks. Chem. Pap. 2025, 79, 3513–3545. https://doi.org/10.1007/s11696-025-04025-4.

  • 51.

    Özkan, U.; Bayram, O.; Şahin, H.T. Effect of Sorption Parameters on the Removal of Malachite Green with Modified Juniperus excelsa Cone Biochar. Biomass Convers. Biorefinery 2025, 15, 25093–25106. https://doi.org/10.1007/s13399-025-06797-x.

  • 52.

    Yıldırım, G.M.; Bayrak, B. The synthesis of biochar-supported nano zero-valent iron composite and its adsorption performance in removal of malachite green. Biomass Convers. Biorefinery 2022, 12, 4785–4797. https://doi.org/10.1007/s13399-021-01501-1.

  • 53.

    Belcaid, A.; Beakou, B.H.; Bouhsina, S.; et al. Biosorption of Cobalt and Chromium from Wastewater Using Manganese Dioxide and Iron Oxide Nanoparticles Loaded on Cellulose-Based Biochar: Modeling and Optimization with Machine Learning (Artificial Neural Network). Int. J. Biol. Macromol. 2024, 282, 136855. https://doi.org/10.1016/j.ijbiomac.2024.136855.

  • 54.

    Jabar, J.M.; Adebayo, M.A.; Odusote, Y.A.; et al. Valorization of microwave-assisted H3PO4-activated plantain (Musa paradisiacal L.) leaf biochar for malachite green sequestration: models and mechanism of adsorption. Results Eng. 2023, 18, 101129. https://doi.org/10.1016/j.rineng.2023.101129.

  • 55.

    Kameliya, J.; Verma, A.; Dutta, P.; et al. Layered Double Hydroxide Materials: A Review on Their Preparation, Characterization, and Applications. Inorganics 2023, 11, 121. https://doi.org/10.3390/inorganics11030121.

Share this article:
Download PDF
Issue
Volume 1, Issue 1
How to Cite
Kumar, S.; Rai, N.; Soni, S.; Kumar, S.; Verma, A.; Arora, C. Effective Removal of Malachite Green Dye on Camellia Sinensis Ash. Environmental Guardian 2026, 1 (1), 3.
RIS
BibTex
Copyright & License
article copyright Image
Copyright (c) 2026 by the authors.
Article Metrics
29
Article Views
0
Citations