Optimization of preparation conditions for activated carbons from polyethylene terephthalate using response surface methodology

Abstract

This work proposes the optimal conditions for the preparation of activated carbons from polyethylene terephthalate (PET) with good surface area and yield. The PET-based activated carbon was prepared using a chemical activation technique employing sulfuric acid (H 2 SO 4 ). Different preparation conditions involving impregnation ratio, activation temperature and activation time were investigated to evaluate their effects on both surface area and yield. The central composite design (CCD) approach was adopted to determine the effects of preparation conditions on responses. Based on the CCD, quadratic models for both surface area and yield were developed. The significant factors for each experimental design response were identified from the analysis of variance (ANOVA). The optimum conditions for PET-based activated carbon preparation were obtained by using an impregnation ratio of 37.63%, activation temperature of 600ºC, and activation time of 30 min, which resulted in 537 m 2 /g of surface area and a 12.57% yield.