Graphene Oxide-based Adsorbents for Pulp and Paper Wastewater Treatment: A Comprehensive Review

The pulp and paper industry generates substantial volumes of complex wastewater containing lignin, dyes, chlorinated organics, and heavy metals, posing significant environmental challenges. Traditional treatment methods are often ineffective in eliminating these persistent pollutants, necessitating advanced solutions. This comprehensive review evaluates the role of graphene oxide (GO) and its derivatives in pulp and paper industry wastewater treatment. Based on a broad synthesis of peer-reviewed studies published between 2015 and 2024, the analysis focuses on pollutant-specific performance, adsorbent types, and treatment efficiencies. The findings demonstrate that GO-based adsorbents outperform conventional materials, achieving removal efficiencies exceeding 90% for lignin, dyes, and heavy metals under optimal pH and contact time conditions. Functionalized GO variants such as GO-ZnO, amine-GO, and GO-polymer hybrids exhibit enhanced adsorption capacities (up to 210 mg/g), faster kinetics, and moderate regeneration potential over 3–5 cycles. Key mechanisms include π–π stacking, hydrogen bonding, and electrostatic attraction. However, limitations remain regarding pilot-scale validation, particularly challenges related to material recovery, process integration, hydraulic performance, and cost scalability as well as long-term stability issues such as adsorbent fouling, structural degradation, and performance loss under continuous operation, along with concerns related to the environmental fate and potential eco-toxicity of GO nanomaterials.The review identifies critical knowledge gaps in mixed pollutant remediation, toxicity assessments, and real effluent application. Future directions recommend green synthesis of GO composites, integration with membrane and photocatalytic systems, and pilot-scale trials under continuous flow. The study underscores GO's potential as a next-generation material for sustainable, scalable, and multi-functional treatment of pulp and paper industrial effluents.