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261.
Innovative simple method for the preparation of simonkolleite-TiO2 photocatalyst with different Zn contents was achieved. The prepared photocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), FT-IR, Raman and diffuse reflectance spectroscopy techniques. The photocatalytic activities of the materials were evaluated for the simultaneous detoxification of hexavalent chromium (Cr(VI)) and oxidation of organic compounds commonly present in wastewater under simulated solar light. The best photoreduction efficiency of Cr(VI) has been achieved at 1000 ppm simonkolleite-TiO2 photocatalyst of 5% Zn/TiO2 weight ratio, and pH value of 2.5 to enhance the adsorption onto catalyst surface. Photoreduction was significantly improved by using formic acid as holes scavenger owing to its chemical adsorption on the catalyst surface. Finally, 100% photoreduction of Cr(VI) could be achieved using formic/simonkolleite-TiO2 systems under sunlight. 相似文献
262.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g. 相似文献
263.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). Thewire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g. 相似文献
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266.
大气挥发性有机物(VOCs)不仅本身具有较强毒性,而且是影响中国区域复合大气污染的重要前体物和参与物。近年来,中国不断加大对VOCs的管控力度,从制定政策体系、建立监测标准等角度采取了一系列的措施。但总体来看,中国大气VOCs控制仍存在许多问题。突出地体现在:基础数据匮乏,排放状况不清;法律法规滞后,污染防治与监管体系不健全;排放标准和监测规范不完善,控制技术亟需革新。基于此,本文从完善法律法规、健全制度体系和加强标准控制等方面提出了加强VOCs管控的思路和对策建议。 相似文献
267.
针对紫外分光光度法测定污水COD值的误差分析问题,给出了实验的仪器和试剂的配制方法,如测试主要仪器设备和主要试剂的配制,介绍了测定水样的采集地点,介绍了重铬酸钾法的测定原理及步骤,重铬酸钾法的测定原理和重铬酸钾法的测定步骤,紫外分光光度法的测定原理及步骤,如紫外分光光度法的测定原理和紫外分光光度法的测定步骤,并对结果进行了讨论,紫外分光光度法,标准曲线的确定,测定的结果比较和方法的准确度和精密度比较. 相似文献
268.
Fe(II)/γ-Al2O3 powders synthesized using the dipping method were produced from a mixed aqueous solution containing aluminium oxide(γ-Al2O3) and iron(II)-precursor(FeSO4), and used for photoFenton degradation of phthalocyanine dyes(PCS) under ultraviolet(UV) irradiation in an up-flow fluidized bed. The catalysts were characterized by XRD, ESCA, BET, EDS and SEM. The results showed that Fe2+ion was compounded on the γ-Al2O3 carrier. The effects of different reaction parameters such as catalyst activity, dosage and solution pH on the decolorization of PCS were assessed. Results indicated that maximum decolorization(more than 95%) of PCS occurred with20 wt% Fe(II)/γ-Al2O3 catalyst(dosage of 60 g/L) using a combination of UV irradiation and heterogeneous Fenton system. The degradation efficiency of PCSincreases as pH decreases, exhibiting a maximum efficiency at pH 3.5. The recycled catalyst was capable of repeating three runs without a significant decrease in treatment efficiency, and this demonstrated the stability and reusability of catalyst. 相似文献
269.
运用Agilent(安捷伦)1200系列高效液相色谱和多环芳烃专用柱ZORBAX Eclipse PAH(4.6×250mm、5μm,P.N.959990-918,S.N.USPAB01066),对16种多环芳烃化合物混合溶液进行分析,根据具体实验条件优化EPA8310中色谱分离条件并得到了更节省时间、分离效率更好的流动相梯度变化程序。 相似文献
270.