Preparation Of High Catalytic Nano-copper And Its Application In Degrading Environmental Pollutants

In recent years,the energy and environmental issues are the focus of attention due to the rapid development of technology and the improvement of environmental requirements of life.In addition,the water environment plays an important role in production activities and life.However,sewage discharge and other pollution problems are increasingly prominent,which not only affects human health and economic development,but also violates the idea of sustainable development and getting along harmoniously with nature.There are many methods of water pollution treatment,but some methods limit a wide range of applications due to high cost and other issues.The research what based on water pollution and practical water-treatment problems has been done as follows in this thesis.?1?Copper nanoparticles?Cu NPs?are synthesized in a simple and short period method,and the effect of adding ammonia and phenol on the synthetic of Cu NPs is investigated.Using X-ray diffraction?XRD?,field emission scanning electron microscopy?FESEM?and transmission electron microscopy?TEM?study the characteristics of as-prepared product.The results indicate adding ammonia and phenol cause Cu NPs which have mean particle size of about 32 nm is formed and the surface of copper nanoparticles is rough.However,cuprous oxide particles are synthesized when the synthetic process has not excluding ammonia,and phenol and the surface of cuprous oxide particles is smooth.Therefore,the additional ammonia and phenol in the process prevent as-prepared Cu NPs from being oxidized into the metastable state copper.And the addition of ammonia and phenol make the resulting copper nanoparticles having small particle sizes and rough surfaces.In this chapter,Cu NPs as catalyst are used to degrade organic pollutants in the environment,organic pollutants including the nitro phenol?4-NP?,rhodamine B?RhB?,methylene blue?MB?,and methyl orange?MO?.The result suggests that Cu NPs can catalyze the degradation of these organic pollutants under the same conditions,and the order of catalytic degradation of these organic pollutants is MB>MO>4-NP>Rh B.Uv-vis spectrophotometer?Uv-vis?is used to record the process of the degradation of different organic dyes and the situationcatalytic degradation under different temperature conditions,and the rate of catalytic degradation and the reaction rate constant under different temperature are calculated to explore how temperature effects the reaction of catalytic degradation.?2?CuCl nanoparticles?CuCl NPs?are synthesized by a convenient,hydrothermal method.The synthetic approach does not include calcination process and the as-prepared CuCl NPs have excellent dispersing property and antioxidant propery.CuCl NPs with antioxidant property are used to catalyze the degradation of organic pollutants and dyes.In order to further explore the catalytic performance of as-prepared CuCl NPs,the synthetic CuCl NPs as catalyst are employed to degrade of nitro phenol pollution and of rhodamine B dye.In this chapter,field emission scanning electron microscope?FESEM?,transmission electron microscopy?TEM?and other optical instruments are used to describe the characteristics of CuCl NPs,and the catalytic reaction process of degrading nitro phenol and rhodamine B are proved to fit first-order kinetics equation.The quasi-first-order kinetic constants of catalytic degradation reaction are obtained by using the first-order kinetics equation,and the quasi-first-order kinetic constants of nitro phenol and rhodamine B were 0.44 min^-11 and 1.00 min^-11 respectively at the temperature of 292 K.In addition,the as-prepared CuCl NPs are also used to investigate the catalytic degradation of solution what contains simultaneously both nitro phenol and rhodamine B.Through the above test and calculation,the conclusion that CuCl NPs have high catalytic performance can be drawn.The cycle performance of CuCl NPs has been explored,and the result shows there is a little reduction of catalytic activity of Cu Cl NPs after 4 cycles which may be due to small amount of CuCl NPs loss in recycling use.The possible mechanism of the cycle of Cu Cl NPs is described in this chapter.These properties of CuCl NPs broaden its application in environmental protection and other areas.?3?The advantages and catalytic performance of the composite catalyst in some aspects have special effect that the single catalyst is not able to achieve,and so many researchers are keen on composite catalyst.By a series of exploration in this chapter shows using simple synthetic method which copper sources are reduced in aqueous solution,the Cu/Cu₂O compounds with different morphology are successfully prepared.And X-ray diffraction?XRD?,field emission scanning electron microscopy?FESEM?and transmission electron microscopy?TEM?are employed to analyze the character of synthetic samples,and make a comparison.Subsequently,the synthetic Cu/Cu₂O particles are applied to catalyze the degradation of organic pollutants in water,including nitro phenol and azo organic dyes.The change of the absorbance value in the maximum absorption peaks is used to assess the catalytic degradation ability of as-prepared Cu/Cu₂O compounds.The results indicate that the catalytic performance of the rhomboid Cu/Cu₂O is better than that of the cuboid Cu/Cu₂O for the catalytic degradation of the above-mentioned organic pollutants,and there is wider gap in catalytic efficiency between rhomboid Cu/Cu₂O and cuboid Cu/Cu₂O with the decrease of temperature when they catalyze the degradation of nitro phenol and azo organic dyes.Finally,the catalytic activity of Cu NPs is compared with Cu/Cu₂O composite having different morphology in catalyzing the degradation of organic pollutants,and discovered that Cu₂O/Cu composites are higher than single catalytic performance of Cu NPs.?4?The cuprous chloride modified by manganese/nickel?Ni/Mn-CuCl?was synthesized and proved by X-ray diffraction?XRD?,X-ray photoelectron spectroscopy?XPS?and Energy dispersive spectrum?EDS?.Subsequently,the degradation of organic pollutants including 4-NP and RhB was compared with that of the unmodified copper chloride.The results showed that under the same conditions the order of catalytic degradation activity for 4-NP was Ni/Mn-CuCl>Mn-CuCl>CuCl>Ni-CuCl However,the order of catalytic degradation for RhB was Ni-CuCl>Mn-CuCl>Ni/Mn-CuCl>CuCl,and this could be due to the pollutant itself structure.