| Material as a basis and pilot of the modern socio-economic progress, plays anextremely important role for the development of human civilization. Developingenvironment-friendly materials, reducing environmental pollution, restoring thedamaged ecological environment, and improving the surrounding of people by makinguse of materials science and technology are an inevitable historical advance. Carbonmaterials have the advantages of stable to chemical, easy to gain, low cost, so they arewidely used in environmental fields, such as adsorption process, organic substancesrecycle and electrochemical reactions. This paper started with surface modification ofmaterial, creatively adopted nonthermal plasma to etch and load functional groups,established the methodology of rapid evaluation of carbon materials properties usingsolid-phase microextraction(SPME) method, and explored the combination ofelectrochemistry with adsorption to enhance the adsorption properties of organicpollutants in the water. The adsorption studies were conducted for the most widelydistributed typical pollutants at atmosphere and in water environment, and providedbasic data and theoretical evidence for modification of carbon materials.The nonthermal plasma was produced by air, under 15.7 kV potential. Thechanges of the materials surface which were treated by the plasma were surveyed usingscanning electron microscopy, Fourier transform infrared spectroscopy, elementalanalysis, thermogravimetric analysis and other modern techniques. The resultsindicated the etching process and oxidation reaction were happened simultaneouslyduring the modifying process. After modification, the surface area and pore volume ofthe carbon material increased, and new functional groups such as C=O, OH wereenriched. Also, the weight loss decreased and stability improved were observed on themodified materials. The fact that the nonthermal plasma was efficient for changing thephysical and chemical characteristics of the material was proved.The adsorption performance and the selectivity of the material were evaluated by adsorption on same gas with same conditions by different modified carbon materialsand different gases by the same modified carbon material, respectively. It was foundthat the material with treatment of 3 to 8 min by nonthermal plasma has bestadsorption performance to organic pollutants; and the adsorption performance of thecarbon materials for weak polar, middle-molecular weight organic compounds(n-butylalcohol, benzene) is improved after modification. The results also showed that theadsorption speed of benzene is greater than that of alcohols in the first 5 min, and withthe extension of the adsorption time, competition adsorption will happen amongdifferent compounds.The adsorption of gaseous organic pollutants by modified carbon material wasdeveloped in the research. Through adsorption experiments by adsorption anddesorption of eight organic pollutants, including benzene, toluene, ethylbenzene andxylene, as well as methanol, ethanol, isopropanol and n-butanol on modified carbongraphite, it was found that the modified fiber has rapid adsorption in the first 5 min,and the balance of adsorption is achieved after 35 min; desorption can be finished in 3min at 200℃. Modified graphite has good adsorption performance on both polar andnon-polar substances, and it has good adsorption performance even after 400 timesusage. The modified graphite fiber is suitable for industrial applications.The adsorption performance of polarity organic pollutants in water wasinvestigated for the modified graphite fiber. It was found that the modified fiber hasvery high adsorption efficiency for methanol, ethanol, isopropanol and n-butanoldissolved in water. The salt content, temperature and the pH values of the watersamples were all have certain impacts on the adsorption of polarity organic pollutantsby modified graphite fiber. It cost 10 min to reach adsorption equilibrium for alcoholsusing modified graphite, and it was easier to reach saturation adsorption capacitycompared with the same conditions in gas sample. The temperature 220℃is enoughto desorb the alcohols absorbed on graphite fiber and 1 min is enough to completedesorption of the alcohols with 240℃.The methods of electro-assisted adsorption of organic pollutants in water by modified carbon materials were probed. It was found that the different substancestructure and polarization voltage both have different effects on electro-adsorption. Asfor isopropanol, the polarization improved its adsorption, and the negative voltageblocked its adsorption; whereas the electrochemical effects is reversed to theadsorption of 2, 4-dichlorophenol. The inproveing of the of the electrolyte was goodfor the eledtro-adsorption, while high concentration will intrduce more ions adsorbedon the material which was for organic compounds before. The electro-adsorption of thecarbon materil was significantly improved in acid solution for isoproanol and 2, 4-DCP.The nitrobenzene in the water was sampled by the modified graphite fiber as asolid-phase microextraction fiber. Concentration of inorganic salts, pH, temperature,adsorption time, desorption temperature and desorption time parameters on the impactof pre-treatment samples were discussed. The adsorbed nitrobenzene was analyzed bygas chromatography-flame ionization detector. The linear range of the method wasbetween 10 and 1000μg L-1, and the detection limit was 5μg L-1, and the approach isshowna good sample preparation method.
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