Bacterial Cellulose Composite for Heavy Metal Removal: A Review

Heavy metal contamination in water bodies poses severe environmental and health risks due to the persistence and toxicity of metals such as lead (Pb), cadmium (Cd), and mercury (Hg). Conventional removal methods, including chemical precipitation, ion exchange, and membrane filtration, suffer from limitations such as high costs, sludge generation, and low regeneration potential. In recent years, bacterial cellulose (BC)-based composites have emerged as a promising alternative for heavy metal remediation. BC, a biopolymer synthesized by bacteria, exhibits unique properties such as high surface area, excellent mechanical strength, and biodegradability. This review explores the properties and synthesis of BC, its modification strategies, and the mechanisms involved in heavy metal adsorption. Various BC-based composites, including those functionalized with graphene oxide (GO), metal oxides, and chitosan, demonstrate significantly improved adsorption capacities compared to conventional adsorbents. A comparative analysis of BC composites with other adsorbents, such as activated carbon, biochar, and polymeric materials, highlights their potential for large-scale wastewater treatment. Challenges related to scalability, cost-effectiveness, and adsorption efficiency under real wastewater conditions are also discussed, along with future research directions aimed at enhancing the industrial viability of BC composites for water purification.