Evaluating adsorption of methylene blue using nanocellulose from fresh coconut fiber

Abstract

This study aims to synthesize nanocellulose from fresh coconut fiber and evaluate its ability to adsorb the organic dye Methylene Blue (MB). Accordingly, it investigated factors influencing MB adsorption in aqueous environments, including pH, adsorption time, MB concentration, and temperature. Analytical techniques included Thermogravimetric Analysis (TGA), X-ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FT-IR), as well as surface morphology analysis using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). These techniques were employed to assess the properties of the material and confirm the successful synthesis of nanocellulose from fresh coconut fiber. The optimal synthesis conditions involved using 12 M sulfuric acid at a 1:10 (w/v) fiber-to-acid ratio, with a reaction time of 45 minutes at 30°C. The results showed that the specific surface area of Nanocellulose was 5.062 m²/g, with mesoporous pores having a diameter of 23.724 Å. The Nanocellulose material exhibited effective MB adsorption in water under optimal conditions: pH 6, adsorption time of 15 h, and initial MB concentration of 25 mg/L. The MB adsorption process followed the Langmuir isotherm model, second-order kinetics, and was predominantly a physical adsorption process.