Construction And Adsorption Properties Of Carbon Nanofiber-carbon Nanotube Three-dimensional Structural Fiber Composite Membrane

In recent years,China has hexavalent chromium pollution incident occurred frequently,causing the surrounding water body pollution,the serious influence of nearby residents drinking water safety and body health,caused the panic across the country,also make the chromium pollution problem to get the attention of the public.Hexavalent complex ion is A kind of harm is very big heavy metal ions,by the U.S.environmental protection agency?EPA?classified as class A carcinogen,so to study the effective removal of new technology and the method has the vital significance.Currently,the main materials used for heavy metal ion adsorption are the modification of electrostatic spinning nanofiber membrane,directly using carbon nanometer materials as adsorbents and so on.The adsorbent has some defects,electrostatic spinning of nanofibers membrane used as adsorbent adsorption performance is low,after modification of carbon nanotubes is likely to cause secondary pollution of water resources and other issues,according to this phenomenon,this article through the use of preoxidation and carbonization technology,electrostatic spinning of PAN nanofibers film preparation into carbon nanofiber membranes with excellent properties on this basis,by PECVD technique,tec,hnique in nanometer fiber surface to grow rich even a layer of carbon nanotubes,adjust PECVD conditions of various parameters of the technique,the preparation of a kind of high specific surface area,pore bulky composite structure materials,used for adsorption of heavy metal ions.The main research contents of this paper include the following three aspects:?1?Currently used for adsorption of heavy metal ions adsorption material was studied,on this basis,put forward by preoxidation and carbonization electrostatic spinning PAN nanofibers membrane method,through continuous regulation of preoxidation and carbonization process parameters,the preparation of the performance and structure to meet the requirements of PECVD growth technique of carbon nanofiber membranes.?2?Passed by PECVD technique in the surface of the carbon nanofibers grow a 'layer of uniform distribution of carbon nanotubes,build a kind of composite structure materials of high specific surface area,through the selection of catalyst,the growth time,growth regulation of power and air pressure inside the cavity for a group to grow carbon nanotubes ideal structure parameters.Through BET test characterization,growth of carbon nanotubes before and after the fiber specific surface area were 12.986 m²g^-1 and 398.127 m²g^-1 developed mesoporous structure on carbon nanofibers,and the pore volume content increasing.?3?Will build a composite structure of the materials used in the study of heavy metal ions adsorption,respectively,through contaminated solution PH,adsorbent additive quantity,pollution liquid initial concentration and the adsorption time to study the adsorption performance.At the same time,the adsorption isothermal of Langmuir adsorption isotherm and Freundlich adsorption isotherm were used to study the adsorption mechanism of adsorption materials.The stripping performance test to the adsorption material,in the first 3 times of the stripping process,the adsorption performance of adsorption material stability remains above 90%,realized the high adsorption and stability of composite structure material circulation characteristics.