Removal of Organic Pollutants – Mycotoxin Ochratoxin A and Pharmaceutical Ketoprofen by Cationic Surfactant Modified Kaolinite

Authors

Abstract

The potential of kaolin modified with a cationic surfactant - hexadecyltrimethylammonium (HDTMA) bromide as an adsorbent for the removal of two different contaminants: mycotoxin - ochratoxin A (OCHRA) and the pharmaceutical - ketoprofen (KET) from buffer solutions (pH 7) was investigated. The amount of HDTMA used for modifcation was equal to 50% of kaolin's cation exchange capacity (CEC). The obtained material (HKR-50) was characterized using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry/thermogravimetric analysis (DSC/TG), and scanning electron microscopy (SEM), confirming successful surface modification of kaolinite with HDTMA. Adsorption experiments demonstrated that HKR-50 exhibited significantly enhanced removal efficiency for both OCHRA and KET compared to unmodified kaolin. Nonlinear adsorption isotherms suggested a complex mechanism involving both hydrophobic and electrostatic interactions between contaminants and HDTMA ions. The data fit well to the Langmuir model, with maximum adsorption capacities of 2.57 mg/g for OCHRA and 1.40 mg/g for KET. These findings indicate that surfactant-modified kaolin is a promising and cost-effective adsorbent for the removal of mycotoxins from animal feed and pharmaceuticals from contaminated water, contributing to environmental protection and public health.

Keywords:

kaolin, surfactant, ochratoxin A, ketoprofen, adsorption
Supporting Agencies
This research was funded by the Ministry of Science, Technological Development, and Innovation of the Republic of Serbia, grant number 451-03-136/2025-03/200023.

References

Alagbe, S. O., I. O. Akinwole, A. I. Ogundiran, L. O. Ajayi, O. O. Agbede, O. O. Ogunleye, and A. O. Arinkoola. 2022. “Adsorptive Removal of Ibuprofen, Ketoprofen and Naproxen from Aqueous Solution Using Coconut Shell Biomass.” Environmental Research, Engineering and Management 78 (2): 28–37. https://doi.org/10.5755/j01.erem.78.2.29695.

Cladière, Mathieu, Grégoire Delaporte, Even Le Roux, and Valérie Camel. 2018. “Multi-Class Analysis for Simultaneous Determination of Pesticides, Mycotoxins, Process-Induced Toxicants and Packaging Contaminants in Tea.” Food Chemistry 242 (May 2017): 113–21. https://doi.org/10.1016/j.foodchem.2017.08.108.

Duarte-Silva, R., M. A. Villa-García, M. Rendueles, and M. Díaz. 2014. “Structural, Textural and Protein Adsorption Properties of Kaolinite and Surface Modified Kaolinite Adsorbents.” Applied Clay Science 90: 73–80. https://doi.org/10.1016/j.clay.2013.12.027.

Kung, King Hsi S., and Kim F. Hayes. 1993. “Fourier Transform Infrared Spectroscopic Study of the Adsorption of Cetyltrimethylammonium Bromide and Cetylpyridinium Chloride on Silica.” Langmuir 9 (1): 263–67. https://doi.org/10.1021/la00025a050.

Lakshmi S, Divya, Vijaya Geetha B, and Vibha Murali. 2024. “From Prescription to Pollution: The Ecological Consequences of NSAIDs in Aquatic Ecosystems.” Toxicology Reports 13 (October): 101775. https://doi.org/10.1016/j.toxrep.2024.101775.

Lopes, Joaldo S., Marcelo L. Morais, Alan I.S. Morais, Roosevelt D.S. Bezerra, Josy A.O. Furtini, and Edson C. Silva Filho. 2024. “A New Method for Reducing Impurities in Clay Minerals.” Applied Clay Science 260 (August): 107539. https://doi.org/10.1016/j.clay.2024.107539.

Mannaa, Mohamed, and Ki Deok Kim. 2017. “Influence of Temperature and Water Activity on Deleterious Fungi and Mycotoxin Production during Grain Storage.” Mycobiology 45 (4): 240–54. https://doi.org/10.5941/MYCO.2017.45.4.240.

Mansouri, Fatma, Khawla Chouchene, Ahmed Wali, Jerome Labille, Nicolas Roche, and Mohamed Ksibi. 2024. “Adsorption of Anti-Inflammatory and Analgesic Drugs Traces in Water on Clay Minerals.” Chemosphere 353 (September 2023): 141469. https://doi.org/10.1016/j.chemosphere.2024.141469.

Marković, Marija, Aleksandra Daković, George E. Rottinghaus, Anđela Petković, Milan Kragović, Danina Krajišnik, and Jela Milić. 2017. “Ochratoxin A and Zearalenone Adsorption by the Natural Zeolite Treated with Benzalkonium Chloride.” Colloids and Surfaces A: Physicochemical and Engineering Aspects 529 (March): 7–17. https://doi.org/10.1016/j.colsurfa.2017.05.054.

Mitrović, Aleksandra A., Miroslav M. Komljenović, and Biljana R. Ilić. 2009. “Research of Possibilities for Use Domestic Kaolin Clays for Production of Metakaolin.” Hemijska Industrija 63 (2): 107–13. https://doi.org/10.2298/HEMIND0902107M.

Obradović, Milena, Aleksandra Daković, Danijela Smiljanić, Milica Ožegović, Marija Marković, George E. Rottinghaus, and Jugoslav Krstić. 2022. “Ibuprofen and Diclofenac Sodium Adsorption onto Functionalized Minerals: Equilibrium, Kinetic and Thermodynamic Studies.” Microporous and Mesoporous Materials 335 (February). https://doi.org/10.1016/j.micromeso.2022.111795.

Ožegović, Milica, Marija Marković, Aleksandra Daković, Milena Obradović, Danijela Smiljanić, George E. Rottinghaus, Vesna Jaćević, Ljubisa Ignjatovic, and Ivana Sredovic Ignjatovic. 2025. “Assessment of Nontoxic Surfactant-Modified Kaolinite for Potential Application as an Adsorbent for Mycotoxins.” Minerals 15 (7): 731. https://doi.org/https://doi.org/10.3390/min15070731.

Slaný, Michal, Ľuboš Jankovič, and Jana Madejová. 2019. “Structural Characterization of Organo-Montmorillonites Prepared from a Series of Primary Alkylamines Salts: Mid-IR and near-IR Study.” Applied Clay Science 176 (March): 11–20. https://doi.org/10.1016/j.clay.2019.04.016.

Smiljanić, Danijela, Aleksandra Daković, Milena Obradović, Milica Ožegović, Francesco Izzo, Chiara Germinario, and Bruno de Gennaro. 2021. “Application of Surfactant Modified Natural Zeolites for the Removal of Salicylic Acid—a Contaminant of Emerging Concern.” Materials 14 (24). https://doi.org/10.3390/ma14247728.

Soto, Rodrigo, Michael Svärd, Vivek Verma, Luis Padrela, Kevin Ryan, and Åke C. Rasmuson. 2020. “Solubility and Thermodynamic Analysis of Ketoprofen in Organic Solvents.” International Journal of Pharmaceutics 588 (March). https://doi.org/10.1016/j.ijpharm.2020.119686.

Spasojević, Milica, Aleksandra Daković, George E. Rottinghaus, Milena Obradović, Danina Krajišnik, Marija Marković, and Jugoslav Krstić. 2021. “Influence of Surface Coverage of Kaolin with Surfactant Ions on Adsorption of Ochratoxin A and Zearalenone.” Applied Clay Science 205 (October 2020). https://doi.org/10.1016/j.clay.2021.106040.

Spasojević, Milica P, Aleksandra S Daković, George E Rottinghaus, Radosavljević-Mihajlović, A.S., Marković, Marija A., and Danina R. Krajišnik. 2019. “ZEARALENONE AND OCHRATOXIN A: ADSORPTION BY KAOLIN MODIFIED WITH SURFACTANT.” Metallurgical and Materials Engineering 25 (1): 39–45. https://doi.org/https://doi.org/10.30544/413.

Werling, Nadja, Jonas Kaltenbach, Peter G. Weidler, Rainer Schuhmann, Frank Dehn, and Katja Emmerich. 2022. “Solubility of Calcined Kaolinite, Montmorillonite, and Illite in High Molar NaOH and Suitability as Precursors for Geopolymers.” Clays and Clay Minerals 70 (2): 270–89. https://doi.org/10.1007/s42860-022-00185-6.

Downloads

Published

30-09-2025

Issue

Section

Innovative Materials in Environmental Protection