Studies On Controllable Preparation Of Functional Porous Carbon And The Separation Properties Of Antibiotics

With the rapid improvement of social economy,the ecological environment that human beings rely on has been seriously damaged.Water pollution is closely related to human activities and has become one of the serious environmental problems in the world.In recent years,the consequences of antibiotic pollution are becoming obvious in many countries.Exploring efficient and economic antibiotic pollution treatments have become the focus of scientists and engineers.Porous carbon materials have rich pore structure and stable physical and chemical properties,which have application prospects in adsorption,energy storage,drug delivery and release,electrocatalysis and other aspects.In this paper,nitrogen doping was used to prepare a variety of functional porous carbon materials and their adsorption behavior was studied as follows:1)Nitrogen-doped carbon spheres(NCS)with regular shape and uniform particle size were prepared by improved St?ber method and applied to adsorb cephalexin.Hexamethylenetetramine(HMT)was used as carbon and nitrogen sources in the synthesis process.Resorcinol and formaldehyde produced by the pyrolysis of HMT were polymerized to form resin spheres catalyzed by ammonia,and in-situ nitrogen doping was achieved.The obtained NCS with regular morphology had high specific surface area and suitable nitrogen doping.NCS was used as adsorbent to test the adsorption property for cephalexin,and adsorption isothermal model,adsorption thermodynamics and adsorption kinetics were used for fitting analysis of its adsorption behavior.2)Nitrogen-doped mesoporous carbon spheres(NMC)were prepared by one-step method.In this experiment,HMT was used as the only carbon and nitrogen source,and tetraethoxysilane(TEOS)was the template.Ammonia produced by HMT pyrolysis provided basic conditions for the system.The silica hydrolyzed by TEOS and carbon precursor formed resin-silica dioxide composite material which was transformed into nitrogen-doped mesoporous carbon after carbonization and template removal.The NMC was used to adsorb antibiotics,and its adsorption behavior was studied by adsorption isothermal model,adsorption thermodynamics and kinetics.3)N-doped hollow carbon spheres(N-HCS)were prepared by using RF resin as carbon source and silica spheres as template.In the experiment,polyvinylpyrrolidone(PVP)not only acted as the nitrogen source,but also as a modifier to provide electrostatic and hydrogen bonding forces between silica spheres and resin.N-HCS and cephalexin were used as adsorbents and adsorbates respectively.Isothermal adsorption model,adsorption thermodynamics and kinetics were analysed.