Biopolymer-Based Flocculation for Microplastic Removal: Fenugreek and Okra as Sustainable Alternatives to Synthetic Flocculants

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Year : 2026 | Volume : 14 | 02 | Page :
    By

    Vivesh Selladurai,

  • Kannan R,

  • Vinod Kumar,

  1. Student, Department of Chemical Engineering, St. Joseph’s College of Engineering, Chennai, Tamil Nadu, India
  2. Student, Department of Chemical Engineering, St. Joseph’s College of Engineering, Chennai, Tamil Nadu, India
  3. Associate Professor, Department of Chemical Engineering, St. Joseph’s College of Engineering, Tamil Nadu, India

Abstract

Microplastic pollution has emerged as a persistent global environmental concern due to its widespread presence in aquatic ecosystems and potential implications for food chains and human health. Conventional removal approaches, particularly the use of synthetic flocculants such as polyacrylamide (PAM), have demonstrated high removal efficiencies in water treatment applications. However, their use is often associated with environmental concerns including toxicity, non-biodegradable residues, and energy-intensive production processes. In this context, the present review critically examines natural biopolymers derived from fenugreek (Trigonella foenum-graecum) galactomannan and okra (Abelmoschus esculentus) mucilage as sustainable, plant-based alternatives for microplastic flocculation. Reported studies highlight the potential of these biopolymers owing to their biodegradability, abundance of hydroxyl and carboxyl functional groups, electrostatic interaction capability, and polymer-bridging behavior. This review synthesizes available literature on their extraction techniques, physicochemical characteristics, flocculation mechanisms, and performance trends reported under laboratory-scale conditions in comparison with conventional synthetic flocculants. In addition, key challenges related to scalability, structural modification, and process optimization are discussed, along with emerging research directions such as hybrid nanocomposites and synergistic polymer blends. Overall, the reviewed literature indicates that fenugreek and okra-derived biopolymers represent promising candidates for environmentally sustainable microplastic removal, while further investigation is required to support large-scale implementation.

Keywords: Microplastics, Fenugreek, Okra, Biopolymers, Natural Coagulants.

How to cite this article:
Vivesh Selladurai, Kannan R, Vinod Kumar. Biopolymer-Based Flocculation for Microplastic Removal: Fenugreek and Okra as Sustainable Alternatives to Synthetic Flocculants. Journal of Polymer & Composites. 2026; 14(02):-.
How to cite this URL:
Vivesh Selladurai, Kannan R, Vinod Kumar. Biopolymer-Based Flocculation for Microplastic Removal: Fenugreek and Okra as Sustainable Alternatives to Synthetic Flocculants. Journal of Polymer & Composites. 2026; 14(02):-. Available from: https://journals.stmjournals.com/jopc/article=2026/view=240450


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Ahead of Print Subscription Review Article
Volume 14
02
Received 30/12/2025
Accepted 03/02/2026
Published 22/04/2026
Publication Time 113 Days
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