Optimum phenol sorption in peat by the response surface method

In this study, the attenuation capacity of peat soil as an adsorbent for the removal of phenol was optimised by conducting laboratory-scale batch experiments using response surface methodology (RSM). The factor-based Box–Behnken experimental design of RSM was applied to examine the combined effect of selected process parameters that is, initial phenol concentration (1–20 mg/l), soil dosage (50–200 g/l) and initial solution pH (2–10), and the percentage phenol removal were considered as a response function. A quadratic model was developed by regression analysis, using the experimental data from 17 batch runs. The predicted values of phenol removal in the model were found to be in close agreement with experimental values (R² = 0·99). With the use of a desirability function, the optimum values of initial phenol concentration, adsorption dose and initial solution pH were found to be 20 mg/l, 80·08 g/l and 6·4, respectively, with a desirability of 0·922. Under these conditions, the phenol removal efficiency was found to be 45·05%.