Optimizing the Removal of Acid Red 14 Onto Chitosan-Based Electrospun Nanofibers Using Surface Response Technique: Adsorption Kinetic Studies Using Linear and Nonlinear Approaches

Abstract

Environmentally friendly chitosan (CS)/polyvinyl alcohol (PVA) mats were produced using electrospinning technology. The fibers were investigated to see if they worked as Acid Red 14 (AR14) adsorbents. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to evaluate the chemical structure and appearance of the fibers. It successfully modeled and optimized the adsorption process using the Box–Behnken design (BBD). This study examined the combination of three independent variables: adsorbent dosage (0.005–0.015 g), pH of AR14 solution (2–12), and initial AR14 concentration (10–100 mg/L) on AR14 removal efficiency (%) in batch systems. The results showed that the polynomial quadratic model could clearly explain the adsorption process as indicated by the high regression parameters (\({R}^{2}\) value = 0.9695, adjusted \({R}^{2}\) value = 0.9302). Furthermore, the proposed model was validated by analysis of variance (ANOVA). According to the model, the optimum value to achieve 80.99% AR14 removal was estimated as 0.01 g nanofiber, 70 mg/L AR14 concentration, and pH of 2.96. The four distinct pseudo-second-order linear kinetic models were used to assess the kinetic data. The best-fitting equation was found using error analysis techniques, such as the coefficient of determination (\({R}^{2}\)) and the chi-square test (χ²). The type 1 pseudo-second-order kinetic model and the pseudo-second-order nonlinear method were found to be appropriate for estimating the adsorption parameters. The findings of this investigation show that the synthesized nanofibers are promising and cost-effective adsorbents for the removal of AR14 from aqueous solutions.