Adsorptive Removal of Bisphenol A by Activated Carbon and its Regeneration Study

Abstract

Bisphenol A (BPA) is mostly manufactured for the plastics industry. It is an intermediate in the production of epoxy resins and polycarbonate plastics. The plastics are utilized in many food and drink packaging productions to line metal food cans, bottle tops and water supply pipes. BPA is an endocrine disruptor that has been shown to alter the structure or function(s) of the endocrine system and causes adverse effects in individuals, their offspring or populations. Effective technologies for BPA removal are limited; therefore the present study was aimed to study the adsorptive removal of bisphenol A (2-2-bis-4-hydroxypheniyl propane) from aqueous solution by using granular activated carbon. The contact time, adsorbent, BPA concentration, temperature and pH were optimized to obtain the maximum removal. A study of the adsorption kinetics, adsorption isotherm, effect of initial pH and effect of ionic strength were carried out. The adsorption capacity was determined by Langmuir, Freundlich and Temkin isotherms. The adsorption kinetics fit pseudo-second-order kinetic model well and the adsorption isotherms follow the Langmuir model. The maximum adsorption capacity (qe) of BPA by activated activated carbon obtained by Freundlich and Temkin isotherms was 241 mg/g and 257 mg/g . The adsorption kinetics and capacity of BPA over granular activated carbon generally depend on the average pore size and specific surface area (or pore volume) Finally, it can be suggested that granular activated carbon possessing high porosity and large pore size can be used as potential adsorbent to remove the harmful endocrine disrupting chemical BPA in contaminated water. Quantitative recovery of BPA was readily achieved by exploiting the reversibility of activated carbon sorption in BPA solutions. Thus, the study demonstrates the potential use of this inexpensive, easily accessible material as a superior sorbent medium for BPA in aqueous media