Preparation of P-doped Coal Pitch-based Porous Carbon and Its Adsorption Performance for Broad-spectrum Antibiotics in Wastewater
P-doped porous carbon(CPCx)was prepared by one-step method with coal tar pitch as carbon,sodium hypophosphite monohydrate as phosphorus sources and MgO as template coupled with KOH activation.CPCx were characterized by SEM,BET,FTIR,XPS,and the adsorption properties of porous carbon for oxytetracycline and chloramphenicol were investigated.When the mass ratio of coal tar pitch to phosphorus source is 2∶1,the BET results show that the total specific surface area and the microporous specific surface area of as-made CPC2.0 are 2739 and 2353 m2/g,respectively,and the average pore size is 3.78 nm.The results of FTIR indicate that the phenyl absorption peak for CPCx is deepened compared to the original carbon,as well as a new stretching vibration peak of P—O is displayed.The XPS results demonstrate that the P content and the most stable C3—P=O functional group content of phosphorus configuration on the surface of carbon materials are 0.45%and 37.7%(molar fraction).The adsorption process of antibiotics by CPC2.0 can be better described by Langmuir model and pseudo second-order kinetic model,and the maximum adsorption capacities of CPC2.0 for oxytetracycline and chloramphenicol are 1780 and 1122 mg/g,respectively,showing better adsorption performance.