ADSORPTIVE REMOVAL OF BISPHENOL-A USING LOW COST ADSORBENT

Abstract

In the past few years, the research on the endocrine disrupting chemicals (EDCs) has been increased with great interest in the area of environmental science and technology owing to the reason that these chemicals (EDCs) have various properties such as estrogenic, antiestrogenic or antiandrogenic and hence their existence leads to the potential damage the endocrine systems of human beings and wildlife. One of the ECDs such as Bisphenol A [2, 2-bis (4- hydroxyphenyl) propane] or BPA is of the important concern due its adverse potentiality to the human health and environment. BPA is mainly used in the manufacturing of resins and polycarbonate plastics. There is chance of entering the BPA into water bodies while manufacturing plastic products, leaching from plastic products, disposed at the landfill sites, and many routes. Thus it causes contaminating the various sources of water such as ground water, surface water, etc. and poses danger to fecundity and reproductive health of human beings and aquatic animals. The present work deals with optimization of various process variables for the removal of BPA from aqueous solutions by cheaply available adsorbent such as Bagasse Fly Ash (BFA) using Response Surface Methodology based Central Composite Design (CCD). The process variables such as BFA dose (w), time of contact (t), initial pH of BPA solution, temperature (T) were varied at five levels to examine the effects on the adsorption of BPA onto BFA and the results were analyzed by Sequential model sum of squares and analysis of variance (ANOVA). The optimum conditions for the removal of BPA were found to be pH = 5.8, adsorbent dose = 17.5 g/l, contact time = 270 min, temperature = 400C. The characterization was done to determine the physicochemical properties, textural properties of BFA. Equilibrium isotherms for BPA-BFA system were studied by Langmuir, Freundlich, Redlich-Peterson, Hill, Sips, Tempkin, Toth isotherm models using a non-linear regression method.