Enhanced adsorption capacity of tetracycline on tea waste biochar with KHCO 3 activation from aqueous solution

摘要: Activation is an important pathway that can enhance the adsorption capacity of biochar. In this study, a modified tea waste biochar (MTWBC) was prepared via two-step pyrolysis approach with KHCO3 activation. Pristine (TWBC) also produced as control one-step without Various characterizations were undertaken to investigate influence modification on morphology, composition, carbon structure, surface area, and functional group biochar, including scanning electron microscope (SEM), area pore analyzer, element analysis, point zero charge (pHPZC), X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), photoelectron (XPS). After activation treatment, total volume, micropore volume MTWBC reached 1981 m2·g-1, 0.8547 cm3·g-1, 0.6439 cm3·g-1 which 7.34-fold, 7.27-fold, 7.30-fold increases, respectively, compared TWBC. The aromaticity, hydrophilicity, polarity increased after modification. More graphitization less defective structures occurred in C-, O-, N-containing groups changed reaction KHCO3. pseudo-second-order Freundlich models best described process maximum tetracycline (TC) 293.46 mg·g-1, 15-fold more than TWBC (19.68 mg·g-1). An alkaline environment decreased TC biochars. presence Na+, K+, Ca2+, Mg2+ inhibited onto Cu2+ by biochars depends its initial concentration. enhanced mainly attributable large improved aromatic structure. mechanism based filling π-π EDA interaction. Therefore, activated has potential remove from aquatic environments.