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91.
转鼓式内电解装置处理水中酸性橙Ⅱ染料 总被引:3,自引:1,他引:3
设计制作了转鼓式内电解反应装置,将铁屑与活性炭按体积比为1:1混匀后装填在转鼓内,对偶氮染料酸性橙Ⅱ(AOⅡ)进行降解实验,考察了溶液pH、转鼓转速和溶液浓度对AOⅡ降解过程的影响.结果表明,AOⅡ降解过程符合准一级动力学方程,酸性条件有利于AOⅡ的降解,转鼓转速过快和溶液浓度过高则不利于AOⅡ的降解.解决了铁炭床长时间运行板结结块的问题.AOⅡ分子在转鼓式内电解的作用下,其可见光和紫外光区的特征吸收峰逐渐降低直至消失,并新生成更容易生物降解的对氨基苯磺酸盐. 相似文献
92.
93.
大气污染带来的危害已明显影响到人民群众的身心健康,菏泽市城区“十五”以来降水监测的酸雨现状表明菏泽市酸雨污染呈逐年加重趋势,指出了菏泽市城区酸雨污染成因和发展趋势,进而提出了改善城市大气环境质量的建议与对策。 相似文献
94.
Decolorization and biodegradation of dye wastewaters by a facultative-aerobic process 总被引:1,自引:0,他引:1
BACKGROUND: Dye wastewater is one of the main pollution sources of water bodies in China. Conventional biological processes are relatively ineffective for color removal, the development of alternative treatment methods will become important. Our subjective was that of introducing a new biotreatment technology which combined a facultative biofilm reactor (FBR) with an aerobic reactor (AR) to treat a dye wastewater. The efficiencies of color and chemical oxygen demand (COD) removal and the mechanism of dye degradation were investigated. METHODS: The anthraquinone acid dye (acid blue BRLL) concentration, organic loading rate (OLR) and hydraulic retention time (HRT) were varied in the experiments to evaluate the treatment efficiency and process stability. The biodegradation products were detected by infrared (IR) and high performance liquid chromatography and mass spectrometry (HPLC-MS). RESULTS AND DISCUSSION: The results demonstrated that the facultative biofilm process was more effective for decolorization than the anaerobic stage of an anaerobic-aerobic process. Most color removal occurred in the facultative reaction (maximum to 88.5%) and the BOD (biochemical oxygen demand): COD of the FBR effluent increased by 82.2%, thus improving the biodegradability of dyes for further aerobic treatment. The dye concentration, OLR and HRT will be the factors affecting decolorization. Color removal efficiency falls as the influent dye concentration increases, but rises with increased HRT. The infrared and HPLC-MS analyses of the effluents of FBR and AR reveal that the dye parent compound was degraded in each reactor during the process. CONCLUSION: The Facultative-aerobic (F-A) system can effectively remove both color and COD from the dye wastewater. The FBR played an essential role in the process. The average overall color and COD in the system were removed by more than 93.9% and 97.1%, respectively, at an OLR of 1.1 kg COD m(-3) d(-1) and at the HRT of 18-20 hours in the FBR and 4-5 hours in the AR. The color removal mechanism in each reactor was not only a sort of biosorption on the floc materials, but even more an effect of biodegradation, especially in the facultative process. Recommendation and Outlook. In applying the F-A system to treat a dye wastewater, the control of facultative processes and the set up of appropriate operation conditions appear to be critical factors. Also, it is suggested a moderate COD loading rate and about a 24-hour HRT will favor the F-A system. 相似文献
95.
96.
采用改进的共沉淀法与溶剂热法相结合制备了ZnFe2O4纳米晶,利用X射线衍射(XRD)、透射电镜(TEM)对ZnFe2O4的晶型和形貌进行了表征,讨论了其表面的光伏效应,以酸性橙Ⅱ的光催化脱色性能作为探针反应,详细地考察了催化剂的用量、底物浓度及溶液pH等因素对其脱色效果的影响.结果表明,制备的ZnFe2O4为正尖晶石型结构,平均粒径为7 nm左右,样品具有一定的捕获电子能力,在外加电场下光伏响应变化明显,在正电场下有最佳响应值,而当负电场达到一定值时,外电场的光伏响应占据主导地位.在酸性橙Ⅱ为20 mg/L、催化剂用量为1.0 g/L的中性条件下,其脱色效率达95%左右,而且经过4次重复使用后催化剂仍然具有一定的脱色性能. 相似文献
97.
石灰—硫酸亚铁法处理高浓度砷和氟酸性废水试验研究 总被引:7,自引:0,他引:7
采用二级石灰-硫酸亚铁法处理砷和氟浓度分别高达110mg/L和650mg/L以上的酸性废水。当一、二级控制条件分别为pH9.5和9.0、Fe/As比为2.5和15时,一级砷和氟去除率分别可达99.5%和94%,二级出口砷和氟残余浓度分别可低至0.1mg/L和13.8mg/L,Cu、Zn和Pb等重金属离子均达检不出水平。 相似文献
98.
99.
Acid hydrolysis of estuarine water samples for the determination of amino acids (AAs) was tested and found to be effective
at high (250 μM) nitrate concentrations when the anti-oxidant, ascorbic acid, was added to the samples. Hydrolysable AA concentrations
were then determined in surface sediments collected from low and high salinity regions of the Tamar Estuary (UK) during winter
2003 and 2004, and in overlying water when simulated resuspension of sediment particles was performed. Concentrations of AAs
in sediment samples comprised <50% of particulate nitrogen, fitting the paradigm that most sedimentary nitrogen is preserved
within an organic matrix. When sediment samples were resuspended in overlying water (salinity 17.5), the rapid, measured increase
in dissolved AA concentrations almost equalled the reported nitrate concentration in the lower estuary, with the subsequent
decrease in the total dissolved AA levels suggested that bacterial uptake was occurring. Our data concur with previous studies
on nitrogen desorption from sediments and suggest that an understanding of organic nitrogen cycling will be an important aspect
of future effective estuarine management. 相似文献
100.
The photodegradation of Acid blue 74 in aqueous solution employing a H2O2/ultraviolet system in a photochemical reactor was investigated. The kinetics of decolorization were studied by application of a kinetic model. The results show that the reaction of decolorization followed pseudo-first order kinetics. We demonstrate that there is an optimum H2O2 concentration, at which the rate of the decolorization reaction is maximum. Irradiation at 253.7 nm of the dye solution in the presence of H2O2 results in complete discoloration after ten minutes of treatment. 相似文献