Optimization adsorption of lead (II) using Aceh natural-bentonite by response surface methodology

Abstract

Response Surface Methodology was employed for the removal of lead on synthetic water. The process parameters including bentonite mass (0.5; 1.25; 2.0 g), lead concentration (10; 55; 100 mg/L), and agitation time (5; 17.5; 30 minutes) were optimized using statistical Box-Behnken Design. The experimental data were obtained and analyzed by analysis of variance (ANOVA) and fit to a quadratic polynomial equation (Regression Analysis, R2 = 0.9996) for 17 runs experiment and 5 runs of the central-point (confidence level at 95%). The numerical optimation was used to identify the optimum condition for maximum removal of lead. The maximum adsorption efficiency expressed as the adsorption capacity, which was found to be 7.42 mg/L, at agitation time 17.5 minutes and adsorbent dosage 2.0 g.