Removal of bisphenol A from aqueous solution using modified fibric peat as a novel biosorbent

Fibric peat was modified with hexadecyltrimethylammonium bromide (HTAB) and its efficiency as a biosorbent for the removal of endocrine disrupting chemical-bisphenol A (BPA) was investigated. The HTAB-modified peat displayed a faster initial BPA sorption and substantially higher capacity than the unmodified peat over a wide concentration range. Kinetic study showed that the sorption followed the pseudo-second-order kinetic model. The maximum sorption capacity of 31.40 mg g−1 was obtained at initial concentration of 45 mg L−1. The BPA sorption to HTAB-modified peat was better described by Freundlich isotherm, while Langmuir isotherm fits better to the BPA sorption against unmodified peat. Comparing with raw fibric peat, the HTAB-modified peat removed more BPA molecules and the desorption rate was much lower. It shows that the improved hydrophobic interactions are the dominant mechanism and the chemical modification of the peat surface greatly enhanced the sorption capacity toward organic compound dissolved in water.

► Fibric peat was modified with hexadecyltrimethylammonium bromide (HTAB) as a biosorbent for the removal of bisphenol A. ► The HTAB-modified peat displayed a faster initial BPA sorption and substantially higher capacity than the unmodified peat. ► The chemical modification of the peat surface greatly enhanced the sorption capacity toward bisphenol A. ► The improved hydrophobic interactions are the dominant mechanism.