| As the most common type of plasticizer in plastic industry, phthalic acid esters (PAEs) is widely applied to plastic plasticizer, pesticide,cosmetics, lubricants, insect repellents and detergent raw material. Meanwhile, as a kind of typical endocrine disruptors, PAEs releases into the natural environment through those products and accumulates in the body through the enrichment of drinking water and food chain, which is not only hard to biodegradable, but also threatening to human health and the environment. So it is significant to seek effective and thorough methods for eliminating DBP.The objective of the thesis focused on the effects of initial pH, the dosing quantity of sodium persulfate (SPS) and catalyst, reaction temperature and reaction time on the reactivity of degradation of DBP in microwave systems. Meanwhile, the best condition and different ROSs’s contribution were determined. The ability of every methods including microwave, Cu/Fe3O4@AC water bathing, SPS water bathing, MW-Cu/Fe3O4@AC, MW- Cu/Fe3O4@AC-SPS to degrading DBP were also compared. In addition, degradation mechanism of catalytic oxidation with the catalyst (Cu/Fe3O4@AC) in microwave systems and DBP potential intermediate products were explored.Through experiments it is concluded that:(1) The major influencing factors of DBP waste water in Microwave strengthening Cu/Fe3O4@AC-SPS system are temperature, time, the dosing quantity of SPS and initial pH. The optimum reaction conditions are:the concentration of Cu/Fe3O4@AC is lg/L; the temperature is 70℃; the reactive time is 25 min; the mole ratio of DBP to SPS is 1:50; the initial pH is 7.0.(2) Increasing reaction temperature can not only helps producing more active site,but also stimulating more oxidizing group, which finally increases the rate of the degradation of DBP. The initial concentration of DBP has an important influence on the degradation rate, and the reaction rate constant reduced from 0.1081 to 0.0938 while and the initial concentration of DBP increased from 1 mg/L to 4 mg/L.when the reaction temperature is 70℃,the maximum reaction rate of degradation rate constant is0.1015Min-1;(3)The contribution ratio of ·OH and SO4-· to degradating DBP is 35.3% and 53.4%,respectively in microwave-Cu/Fe3O4 @ AC system, while other ROSs in the photocatalytic process contributes to the degradation of DBP is only11.3%. SO4·plays a lead role on the degradation of DBP and the degradation products mainly include holomog of PAEs, phenols aldehydes and organic acids etc.In addition, its degradation pathway may be experienced isomerization, aromatic rings with hydroxyl, ring-rupturing reactings and degradation of organic acids etc.(4) Using microwave strengthening Cu/Fe3O4@AC-SPS system to dispose DBP wastewater treatment, has significantly higher removal rate than single microwave radiation, the Cu/Fe3O4@AC of water bath, SPS bath, microwave-SPS, microwave-Cu/SPS Fe3O4@AC, microwave heating, Cu/Fe3O4@AC adsorption and catalytic effect, SPS strong oxidation effect synergy. Under the effect of microwave, the gap between activated carbon which is a good adsorbent, can gather internally high temperature in short time leading to many "arc" formed on activated carbon surface, which can pyrolysis the organic matter adsorbed and produce empty seats in the surface of activated carbon adsorbing DBP again.At the same time, the metal ions coordinated activation of microwave activated carbon and its load SPS can produce free radicals in catalytic degradation of organic matter. |
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