| With the development of industry,industrial waste has caused serious pollution.Among them,water pollution is one of the main problems.The pollutants will endanger human health through various ways.The hexavalent chromium(Cr(Ⅵ))often contained in electroplating wastewater is highly toxic and difficult to remove.It is easy to cause carcinogenic,teratogenic and mutagenic mutations,and has been listed as one of the carcinogenic heavy metals.Bisphenol A(BPA)as a carcinogenic phenolic micro-pollutant which is often contained in plastics,it can still seriously damage human health when the content is very low.Therefore,it is of great significance to select high-efficiency technologies and materials to treat industrial wastewater and reduce toxicity.Because the adsorption-redox method is easy to operate,low cost,and can reduce the toxicity of pollutants,its processing efficiency depends on the performance of the adsorbent(specific surface area,stability,etc.)and the specificity of the composite material for degradation of pollutants.In this paper,UiO-66 material with extremely strong stability in water is selected as the research basis,porous carbon material with ultra-high specific surface area and polyaniline composite material with reducing ability are prepared,and it is used for the adsorption of high concentration BPA And Cr(VI)degradation.The main research contents are as follows:Ultra-high specific surface area nitrogen-doped carbon materials(NC)were obtained by high-temperature carbonization and acid treatment.The effects of different carbonization temperatures on the morphology and defect level of NC were studied.The successful preparation of NC is carried out by a field emission scanning electron microscope(SEM),high resolution transmission electron microscopy(TEM),X-ray diffffraction(XRD),Raman spectroscopy(Raman),X-ray photoelectron spectroscopy(XPS)and N2 adsorption-desorption isotherms(BET))and so on.At the same time,the adsorption performance of NC to BPA(40 mg/L)was also studied.The influence of pH,sodium chloride(NaCl)concentration,humic acid(HA)concentration and other influencing factors on the adsorption was mainly studied,the regeneration performance and the reuse performance were also explored,and the practical application potential of NC and the potential of removing other pollutants were tested.The experimental results show that:the obtained NC-600 can fast remove 40 mg/L of BPA within 30 min;this experiment conforms to the quasi-second-order kinetic model and Freundlich isotherm model;in addition,NC-600 has excellent reproducibility And reusability,and also has the potential to efficiently remove tetrabromobisphenol A(TBBPA),tetrachlorophenol(4-CPs)and Cr(Ⅵ).Secondly,in order to further study the removal of Cr(Ⅵ)by NC-600,this subject prepared a polyaniline/nitrogen-doped carbon material(PANI@NC)composite material to achieve the reduction of Cr(Ⅵ).The successful synthesis of PANI@NC is proved by characterization techniques such as SEM,TEM,XRD and XPS.In the experiment,the influence of pH,concentration,dosage,coexisting ions,etc.on the degradation of Cr(Ⅵ)by PANI@NC was analyzed.Related experiments were conducted on the reuse performance and practical application potential of PANI@NC The removal mechanism of Cr(Ⅵ)by PANI@NC is proposed.The experimental results show that the maximum adsorption capacity of PANI@NC-600 reaches 198.04 mg/g for Cr(Ⅵ)solution with a concentration of 80 mg/L at pH=1.The experimental process conforms to the pseudo-second-order kinetic model and follows the Langmuir isotherm model.In addition,PANI@NC-600 has excellent reusability and practical application potential.In summary,this paper uses UiO-66 as the precursor to prepare porous carbon with a specific surface area much higher than that of commercially available carbon materials,and uses Cr(Ⅵ)and BPA as the target pollutants to discuss the adsorption properties of the sample.This paper provides a research basis for waste-water treatment. |
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