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With the increase in environmental pollution, one of the current major issues is preserving the already degraded environment by preventing the improper disposal of effluents. Pollution can be defined as any physical, chemical, or biological change that can alter an ecosystem. With the substantial production and consumption of chemical products in industries worldwide, the effluents they generate pose a significant concern for the well-being of exposed organisms due to the potential toxicity of some compounds when accumulated within organisms. In response, water and effluent treatment technologies have gained prominence to minimize the damage caused by potentially harmful substances in the environment. One technology that stands out for its efficiency in removing pollutants at a reduced cost is adsorption, which employs cheaper and biodegradable materials such as natural polysaccharides. The study aims to synthesize hydrogels based on pectin modified with glycidyl methacrylate and composite hydrogels with the addition of montmorillonite for adsorption studies on the removal of metals Cd, Cu, Mn, Ni and Zn from aqueous samples. The adsorbent hydrogels underwent Fourier transform infrared (FT-IR) characterization, revealing the presence of carboxylic and vinyl groups within their structure. The swelling degree of the pectin-based hydrogel varied depending on the type of solution, being more pronounced in distilled water. Adsorption capacities of pollutants on the hydrogel networks varied with factors such as adsorption time, pH of the aqueous solution, initial concentration of the pollutant, and solution temperature. Using the Freundlich isotherm, the best performance for Cu adsorption was achieved, allowing for the correlation of surface heterogeneity of the hydrogels. By applying pseudo-first-order, pseudosecond-order, and Elovich adsorption kinetics, it was possible to determine the most suitable model for each pollutant on each hydrogel. Overall, composite hydrogels with montmorillonite exhibited superior adsorption capabilities compared to pectin-based hydrogels without montmorillonite addition. Therefore, both pectin-based hydrogels and composite hydrogels with montmorillonite addition show promise as matrices for the decontamination of water and effluents contaminated with metals.