Adsorbent performance of nipa (nypafruticans) frond in methylene blue dye degradation: Response surface methodology optimization

Abstract

This study primarily focused on optimizing the performance of nipa (Nypafruticans)frond as an adsorbent for methylene blue (MB) dye, using the response surface methodology (RSM). The process of preparing nipafrond includes several key steps, such as washing, drying, and size reduction to 100 mesh. Subsequently, the adsorbent is activated using a 5%v/v HCl activator for 24 hours, and it is characterized by its functional groups using Fourier transform infrared spectroscopy (FT-IR). The composition of both the natural and activated nipa frond is examined through X-ray fluorescence (XRF), while the surface area of the samples is characterized using Brunauer-EmmettTeller surface srea (BET) analysis. The adsorption characteristics are then tested as a function of two independent factors, including adsorbent mass (2.0, 3.0, and 4.0 g) and contact time (80–100 minutes), with an initial concentration of 50 mg/l MB. The statistical analysis, specifically analysis of variance (ANOVA), shows the substantial influence of these variables on the adsorption process. By applying the RSM model, the optimal conditions for MB adsorption are determined. These optimal conditions include nipa frond powder mass of 3.7071 g and a contact time of 83.1142 minutes, resulting in an optimum adsorption capacity of 2499 mg/g. The corresponding optimum adsorption efficiency is 99.7224%, with a desirability value of 0.974.