The effective removal of synthetic dyes such as Janus Green from aqueous solutions is a critical focus in environmental chemistry due to their persistent toxicity and harmful effects on ecosystems and human health. As a cationic dye, Janus Green presents significant challenges for wastewater treatment, demanding innovative and sustainable approaches to adsorption [1]. In this study, cellulose acetate nanoparticle was utilized as an eco-friendly adsorbent, with a novel focus on its in-situ synthesis using the antisolvent precipitation method [2]. This technique involves dissolving cellulose acetate in a suitable solvent, followed by the rapid addition of a non-solvent (antisolvent) under controlled conditions, leading to the precipitation of nanoparticles. The antisolvent precipitation process enables precise control over particle size and morphology, enhancing surface area and adsorption efficiency. By forming nanoparticles directly inside the dye solution, the method eliminates additional synthesis steps and ensures a homogeneous dispersion of adsorbent particles [3]. This in-situ approach offers distinct advantages for adsorption applications, maximizing contact between Janus Green dye molecules and the cellulose acetate nanoparticles, thereby improving removal efficiency. The resulting system is highly effective and provides a sustainable, scalable, and environmentally friendly alternative for wastewater treatment. The influences of parameters including solution pH, temperature, dosage of adsorbent, and contact time have been investigated to find the optimum adsorption conditions. The optimum pH for removing the investigated cationic dye was found to be 8.0 and the maximum predicted adsorption capacities for JG dye was obtained as 62.7 mg g −1 .
