Preparation Of Monolithic Porous Carbon Materials And Study On High-Efficiency Antibiotic Separation

With the extensive use of antibiotics,more and more antibiotics enter the environmental media through various ways.After long-term accumulation and biological chain transmission,the residual antibiotics in the environment will not only cause adverse effects on the ecological environment,but also lead to the production of drug-resistant bacteria,and even endanger human health.Therefore,it is necessary to find a green and efficient method to remove or degrade this kind of pollutants.The commonly used treatment techniques include biological method,chemical method and adsorption method.Adsorption method is widely used in water treatment because of its rapidity,economy and ability to remove soluble and insoluble pollutants,even biological pollutants.However,the performance of adsorbent is the most important factor to determine the quality of adsorption technology.Therefore,it is very necessary to prepare excellent adsorbents.Porous carbon materials with high specific surface area and pore volume,rich pore structure,as a new type of environmental functional materials,can be used as high performance adsorbents,and have a strong adsorption capacity for organic pollutants.In this paper,the preparation of porous carbon materials with different morphologies and the test of their adsorption properties for antibiotics were studied.The main research contents are as follows:1)Synthesis of mesoporous tubular carbon?MTC?and its adsorption properties for antibiotics:MTC have attracted increasing attention due to high specific surface area and rich pore structure.In this work,MTC were synthesized by using resin as carbon precursor,natural tubular Halloysite and F127 as hard-soft templates respectively.The resulted MTC copied the tubular structure of Halloysite.The addition of F127 not only created more abundant pores,but also greatly improved the surface area.The N₂ adsorption experiments showed that the MTC possess a large specific surface area?1034 m²/g?and large pore volumes?2.62 m³/g?.The TEM of MTC showed an obvious tubular structure with abundant mesoporous structure.The strategy may offer a low-cost and scalable method to produce high-performance adsorbent by using inexpensive natural product as a template.The adsorption properties of Cefalexin in water were studied.And the adsorption effect and application prospect were further analyzed in combination with adsorption kinetics and adsorption isotherms.2)Preparation of nitrogen-doped hollow,yolk-shell and solid structure carbon spheres and their adsorption properties for antibiotics:Here,we reported controllable synthesis of hollow,yolk-shell and solid structure carbon spheres via template-free assembly method.Ethanediamine was used as nitrogen source to realize in-situ nitrogen doping and as basic catalyst to drive resorcinol-formaldehyde?RF?resin polymerization.The polymerization degree of internal RF resin tremendously depended on polymerization time,resulting in different levels of heterogeneity of the whole RF resin sphere.This fact made the structural adjustment of carbon spheres from hollow,to yolk-shell and even to solid structure after dissolution of low-molecular-weight RF resin by organic solvents and annealing treatment.As an adsorbent,carbon spheres with yolk-shell structure exhibited excellent adsorption properties,which may be attributed to its unique structure,high specific surface area?1263 m²/g?and pore volume?0.68 cm³/g?.The strategy of making full use of the difference of polymerization degree of resin provides a new idea for the structural engineering of functional carbon materials.3)Preparation of N-doped mesoporous carbon sheets/hollow carbon spheres composite and study on its adsorption properties of antibiotics:Basing on the inhomogeneity of 3-aminophenol/formaldehyde?3-AF?polymerization spheres,the hollow 3-AF spheres were obtained after the dissolution of internal 3-AF oligomer.The dispersed 3-AF oligomer reassembled with silicate oligomers on the hard template of Mg?OH?₂ sheets and hollow 3-AF spheres linked by CTAB through electrostatic force.The obtained N-MCS/HCS possessed both sheet and sphere structure,showing high specific surface area and uniform mesoporous distribution.The adsorption properties of Cefalexin in water were studied,And the adsorption effect and application prospect were further analyzed in combination with adsorption kinetics and adsorption isotherms.4)Study on preparation of fluffy mesoporous carbon spheres and their adsorption properties for antibiotics:a novel dissolution-reassembly method is developed for the fabrication of rich porous carbon spheres with good adsorption properties.The resorcinol-formaldehyde?RF?resin is firstly synthesized then completely dissolved by acetone into oligomer fragments which further reassemble with F127 to form new structured resin spheres.After carbonization,porous carbon spheres?PCS?are obtained.The obtained PCS have regular spherical morphology,rich porous structure,high specific surface area and pore volume.