Microwave Preparation of Modified Activated Carbons for Phenol Adsorption in Aqueous Solution

Abstract

Microwave energy was used to prepare modified activated carbons (GAC, GAC/MW, GAC/Ni, and GAC/Cu). The modified activated carbons were used for phenol adsorption in aqueous solution. The adsorption conditions were optimized. Adsorption capacities of the different modified activated carbons were evaluated. The effect of microwave pretreatment of activated carbons was investigated. A comparative study on the activated carbons adsorption capacities was also investigated. Under optimal conditions the results showed that there was no obvious effect on activated carbons adsorption when rising temperature and pH during the adsorption process. Stirring has a very high effect on the activated carbons adsorption capacity. The adsorption capacity of the modified activated carbons reaches 95%. MW/GAC, GAC/Ni and GAC/Cu adsorptive capacity was higher compared to the Granulated Activated Carbon (GAC) used as received. GAC treated with microwave energy has highest adsorption capacity. The adsorption capacity of GAC loaded with ion Ni2+ is higher than the activated carbon loaded with Cu2+. The untreated GAC has the lowest adsorption capacity. These results can be explained by the effect of microwave irradiation on GAC.The activated carbon loaded with Ni2+ adsorbs more microwave energy than the GAC loaded with Cu2+.