ABSTRACT
Magnetic phosphorous biochar ï¼MPBCï¼ was prepared from Camellia oleifera shells using phosphoric acid activation and iron co-deposition. The materials were characterized and analyzed through scanning electron microscopy ï¼SEMï¼ï¼ X-ray diffractometry ï¼XRDï¼ï¼ specific surface area and pore size analysis ï¼BETï¼ï¼ Fourier infrared spectroscopy ï¼FT-IRï¼ï¼ and X-ray photoelectron spectroscopy ï¼XPSï¼. MPBC had a high surface area ï¼1 139.28 m2·g-1ï¼ and abundant surface functional groupsï¼ and it could achieve fast solid-liquid separation under the action of an external magnetic field. The adsorption behavior and influencing factors of sulfamethoxazole ï¼SMXï¼ in water were investigated. The adsorbent showed excellent adsorption properties for SMX under acidic and neutral conditionsï¼ and alkaline conditions and the presence of CO32- had obvious inhibition on adsorption. The adsorption process conformed to the quasi-second-order kinetics and Langmuir model. The adsorption rate was fastï¼ and the maximum adsorption capacity reached 356.49 mg·g-1. The adsorption process was a spontaneous exothermic reactionï¼ and low temperature was beneficial to the adsorption. The adsorption mechanism was mainly the chemisorption of pyrophosphate surface functional groups ï¼C-O-P bondï¼ between the SMX molecule and MPBC and also included hydrogen bondingï¼ π-π electron donor-acceptor ï¼π-πEDAï¼ interactionï¼ and a pore filling effect. The development of MPBC adsorbent provides an effective way for resource utilization of waste Camellia oleifera shells and treatment of sulfamethoxazole wastewater.
