Functionalized soy waste biomass - A novel environmental-friendly biosorbent for the removal of heavy metals from aqueous solution

In order to make the biosorption process more suitable for industrial applications, soy waste biomass (a low-cost waste, resulted after oil extraction) was functionalized with industrial sulphur based chelating agent, which is a precipitation agent used in industrial wastewater treatment, and used for the removal of some heavy metals from aqueous solution. The experimental conditions for biosorbent functionalization were selected considering the efficiency of obtained biosorbent in the removal of Pb(II) ions from aqueous solution, and these were found: a mixing ratio of industrial sulphur based chelating agent solution and SWB of 0.2 mLg(-1), and a temperature of 30 degrees C. The equilibrium and kinetics analysis of Pb(ll), Cu(II) and Ni(II) biosorption on functionalized soy waste biomass (SCA-SWB) was examined in batch systems, at room temperature (20 +/- 2 degrees C), compared with raw soy waste biomass. The biosorption capacity of SCA-SWB has increased with 196% for Pb(II) ions, 131% for Cu(II) ions and 128% for Ni(11) ions, respectively. The exhausted biosorbent can be easily regenerated with 0.1 M HNO3 solution, and the regenerated SCA-SWB biosorbent can be used in at least five biosorption/desorption cycles. The tests performed with real wastewater samples and some economic considerations indicate the potential of SCA-SWB as suitable alternative biosorbent for the removal of heavy metal ions with industrial applications. (C) 2018 Elsevier Ltd. All rights reserved.