| At present,most of the pollution in the environment exists in the form of compound pollution,in which the heavy metal-organic compound pollution is more common.In real life,industrial production wastewater,domestic water and livestock and poultry breeding wastewater composition is complex and changeable,heavy metal copper and antibiotics Pefloxacin at the same time there is a great possibility.The carbon nanotubes?CNTs?have the advantages of large specific surface area,small particle size and high adsorption capacity,and the adsorption of carbon nanotubes on various organic and heavy metals in water.Therefore,carbon nanotubes as an adsorbent has been the focus of extensive research scholars.The characterization results show that the modified multi-walled carbon nanotubes are more dispersible,the structure did not undergo a major change;The pH of the isoelectric point is about 3.5.In the adsorption of copper alone,the adsorption capacity of O-MWCNTs slightly increased,from 20.609 mg·g-1 before modification to 29.6619 mg·g-1,the adsorption process of the two materials is more consistent with Langmuir model,that is,adsorption for the single layer adsorption,the adsorption capacity of O-MWCNTs is better than that of MWCNTs.It is presumed that the functional groups such as carboxyl groups?-COOH?and hydroxyl groups?-OH?are introduced on the oxidized multi-walled carbon nanotubes,and the dispersibility is also improved.More bit of adsorption.In the adsorption of peofloxacin alone,it can be seen that the removal effect of O-MWCNTs under neutral conditions was significantly higher than that of MWCNTs.The experimental data of adsorption capacity of MWCNTs are more consistent with Langmuir model,which is the single adsorption and the maximum adsorption capacity is 172.430 mg·g-1;While the O-MWCNTs are more in accordance with the Freundlich model and the maximum adsorption capacity is 224 mg·g-1,It is presumed that the adsorption capacity of the surface adsorption sites is no longer uniform due to the appearance of many different types of oxygen-containing functional groups,making the adsorption process a complicated adsorption process.In the system of coexistence of copper and pefloxacin,low concentration of copper has a good effect on high concentration of pefloxacin,and with the increase of copper concentration,the removal effect is decreased;similarly,with the concentration of pefloxacin slowly increased to a certain concentration,the high concentration of copper ion removal has a certain role in promoting,continue to enhance the concentration of pefloxacin will reduce the removal of copper effect.Presumably because Cu???and PEF will form a common structure that no longer compete with each other for adsorption sites,but both complexed product is increased,the required increase in adsorption energy,adsorption sites consumed increases,so can only enhance Cu???,or the PEF adsorption efficiency in a range of concentrations. |
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