Enhanced adsorption of Cu(II) and aniline from wastewater by eggshell biochar: Preparation, performance, mechanism

The removal of combined pollution of heavy metals and antibiotics in an industrial wastewater remains challenging. The inexpensive and high efficient adsorption technology for Cu(II) and aniline removal has caused widespread concern. Hence, A novel eggshell biochar (ESBC) adsorbent by the simple pyrolysis and KMnO 4 modified was prepared. Results of Electronic Data Systems (EDS) and X-ray diffraction(XRD) analyses indicated that aromaticity, hydrophilicity and polarity increased and more oxygen-rich functional groups were formed on ESBC. More notably, Kinetics,thermal dynamics and adsorption and desorption in double-solute systems show that the ESBC exhibits the excellent adsorption capacity for Cu(II) (20.00 mg/g) and aniline (9.71 mg/g), the adsorption process of Cu(II) and aniline followed pseudo-second-order kinetic model and was well fit the Freundlich isotherm model. Combining Fourier Transform Infrared Spectrometer (FTIR) and Scanning Electron Microscope analysis, Cu(II) adsorption was dominated C O and C-H functional groups complexation and electrostatic attraction, whereas aniline adsorption relied on π-π stacking, hydrogen bonding, and physical pore-filling. The excellent performance and stability of ESBC show its substantial potential as adsorbent for the treatment of combined pollution in wastewater. • A novel adsorbent ESBC is prepared by the simple pyrolysis and KMnO 4 modified. • ESBC exhibits the excellent adsorption performance of Cu(II) and aniline. • Cu(II) and aniline adsorption relies on complexation, π-π stacking and hydrogen bonding. • ESBC is a inexpensive and high efficient adsorbent for double-solute removal.