| Today, the pollution of water body becomes more and more serious and many rigorous laws have been made for protecting environment. Accordingly, it is more and more necessary and difficult to treat high-concentration organic wastewater of high color and hard biodegradation. In this thesis, an ultrafine material - MnO2, which had good adsorption performance, was synthesized with cheap raw materials and handy-way. Based on the studies of its physical and chemical properties, the idea of treating high-concentration organic waslewater with fresh MnOz was put forward for the first time. And the removal of treatment efficiency was investigated systematically.The main research aspects are as follows:(1) The foundation of the method of determining CODcrIn experiment, the reagent matched with AL-34 type CODcr measurer (from AQUALYTIC com. in Germany and DR/2010 type CODCr (from Hach in American) has been obtained using Potassium Dichromate 梀isible Spectrophotometer Metric Method(2) The synthesis and characterization of fresh MnO2The fresh MnO2 was prepared by reducing method with the raw materials of MnSO4 and KMnO4. Moreover, it was determined by XRD, TEM, BET, IR, etc. The results suggested that the MnO2 synthesized was 6 -type, with quasi-spherical shape, mean size 250nm, surface area 94.18m2/g. And it was also found that its surface was rich in hydroxyl.(3) The study on the treatment efficiency of high-concentration water-soluble organic wastewater on fresh Mn02 and the regeneration of theinadsorbent.Among the high-concentration organic wastewater, the treatment efficiency of two, the Alkaline Straw Pulping and Paper Black Liquor and printing and dyeing wastewater, was tested in detail.It was found that as a new adsorbent, fresh MnO2 not only had good removal rates of color, COD and TOC to two kind of organic wastewater, but also had such outstanding characterizations as easy operation, quick adsorption, small amount of MnO2 added and high adsorption capacity compared with other adsorbents, which can save treatment period and cost greatly. During experimental process, contact time, the amount of MnC>2 added, wastewater concentration and temperature affected the treatment efficiency in varying degrees. But among all the influencing factors, the pH value of the Mn02 suspension system before adsorption was the main factor, and acid medium was very favorable for adsorption.The results also indicated that the suitable experimental condition to Black Liquor studied was: pH 1.3-1.5, contact time 60min, the amount of MnO2 added 0.5g/L. In addition, under the above-mentioned conditions, the removal of COD and color was 61.4% and 91.3% respectively .The experimental condition to printing and dyeing wastewater studied was pH 1.5-2.5, contact time 30min, the amount of MnCn added 0.5g/L, the removal of COD and color was 53.7% and 78.1% respectively.In order to provide scientific basis for industrialization in the coming years, the preliminary study on the regeneration of the adsorbent after treating Black Liquor has been done .The lignin adsorbed by MnO: was made into activated carbon using ZnCb as an activating agent at high temperature in this thesis. Moreover, the adsorbent regenerated was used to treat Black Liquor. The result showed that the property of adsorbent after regeneration was as good as or more than that of fresh MnOz. The removal of COD and color wasIV53.7% and 94.9% respectively(4) The study on the mechanism of removing organic material on fresh MnO2On the basis of above experimental results, the removal of TOC of 42 model organic molecular compound at vary pH values, and through determination of modern analysis technology, it was regarded that the treatment efficiency on fresh MnOa was due to interface adsorption. Under the condition of acid solution, the fresh MnC^can probably form out-sphere or in-sphere complexes. As a result, the organic material was removed from water.The outcome of the research in this article would provide both a new adsorbent for...
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