Bio-sorption of bisphenol a by the dried- and inactivated-lichen (Pseudoevernia furfuracea) biomass from aqueous solutions

Abstract

Bisphenol A (BPA), which is known as one of the endocrine-disrupting chemicals (EDCs) with hydrophilic hydroxyl groups and hydrophobic aromatic groups, has been widely used in plastic industries. The chemical waste from the industry is sometimes discharges into lakes and rivers, and then these surface waters can be polluted. So, this article aims to investigate the bio-sorption process of BPA by the inactivated lichen (Pseudoevernia furfuracea) biomass from aqueous solution. At initial, the effect of the variables such as initial BPA concentration, solution pH, temperature, contact time and recovery rate on the bio-sorption process was investigated. From the optimal results, it has been observed that the highest removal efficiency is approximately 64% at a contact time of 3-h, the bio-sorbent concentration of 9mg/L, initial BPA concentration of 40mg/L, and agitation speed of 150rpm at pH5.0. In explaining the bio-sorption potential of lichen biomass, Langmuir and/or Redlich-Peterson isotherms with two and three parameters, respectively were observed to be better fit with the experimental isotherm data (R2 = 0.982). From equilibrium data based on difference between the measured and predicted results (qe, exp and qe, pre), it was shown that biosorption of BPA could be best described by the pseudo second order kinetic model with minimum sum of square error of 2.61%. In addition, it shows more film diffusion, and partly pore diffusion in linearity region in terms of kinetic sorption behaviors of BPA in the rate-limiting step as well as intra-particle diffusion according to Boyd's kinetic model with better regression coefficient than 0.981 when compared to the other used kinetic models, including Bangham's pore diffusion and Elovich kinetic models (with R2 of 0.958 and 0.929). The thermodynamic studies showed that the biosorption process was spontaneous, and chemically feasible. Therefore, due to be low-cost, eco-friendly character, wide availability and easily accessible, the lichen biomass could be used as a promising bio-sorbent for the removal of BPA from the environment and wastewater effluents.