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为开发一种简单经济的湿法脱硝新工艺,采用浸渍法制备沸石载体负载Fe_2O_3的非均相类Fenton催化剂,并对其进行表征,同时考察了H_2O_2浓度、初始pH、催化剂质量浓度和反应温度对Fe_2O_3/沸石催化剂非均相类Fenton湿法脱硝效率的影响。结果表明,Fe_2O_3/沸石催化剂具有较大的比表面积,载体结构没有改变,活性组分Fe_2O_3均匀分散在载体上; Fe_2O_3/沸石催化剂具有明显的催化活性; H_2O_2浓度、初始p H、催化剂质量浓度和反应温度在最佳条件下,NO的脱除效率达52%;催化剂具有较好的稳定性,循环使用5次依然有48%左右的NO脱除效率。 相似文献
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采用过量浸渍法制备活性炭负载Fe催化剂(Fe/AC),并以电镀废水作为处理对象考察了H_2O_2投加量、p H值以及反应时间等因素对异相Fenton反应的影响,同时在优化条件下开展了连续异相Fenton试验。结果表明,催化剂活性组分为α-Fe_2O_3、负载量为13.3%;优化后的反应条件为:pH值为3.0,反应时间为1.0 h, H2O2(30%)投加量为500 mg/L。在此优化条件下, Fenton反应对电镀废水中的CODCr具有明显的去除效果, H_2O_2的利用率在27%~62%之间波动,催化剂可在一定时期内维持其催化稳定性。 相似文献
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以Al_2O_3为载体,RuCl_3·xH_2O和FeCl_3·6H_2O为活性组分前驱体,采用吸附-沉淀法制备了Ru-Fe/Al_2O_3和Ru/Al_2O_3催化剂,以马来酸二甲酯加氢合成丁二酸二甲酯为探针反应,结合H_2-TPR和XRD表征技术,考察Fe改性Ru基催化剂的氧化-还原性能及催化活性。经氧化-还原循环处理后,催化剂Ru-Fe/Al_2O_3上马来酸二甲酯加氢活性高于Ru/Al_2O_3。XRD结果显示,经处理的Ru-Fe/Al_2O_3上未见金属Ru的特征衍射峰,而Ru/Al_2O_3上出现了金属Ru的特征衍射峰。结合H_2-TPR结果推断,Ru与Fe之间发生了相互作用,这种协同作用可以改善Ru/Al_2O_3催化剂的热稳定性。 相似文献
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在Al_2O_3负载的镍基纳米催化剂作用下进行了4-甲氧基苯酚催化加氢反应,然后使用双氧水对加氢反应液进行催化氧化合成4-甲氧基环己酮。在催化加氢反应中,考察了沉积-沉淀法和浸渍法及反应条件对催化剂活性和稳定性的影响。通过XRD、H_2-程序升温还原(H_2-TPR)及TEM等对催化剂进行了表征,结果发现,沉积-沉淀法制备的Ni/Al_2O_3-DP催化剂中活性粒子分散度高、粒径较小,并且活性粒子与载体之间有较强的作用力,具有比浸渍法制备的Ni/Al_2O_3-IMP催化剂更好的活性和稳定性。在4-甲氧基苯酚的加氢反应中,以Ni/Al_2O_3-DP为催化剂,最佳的反应条件为:反应温度423 K、反应压力4.0 MPa、反应时间1.0 h、m(4-甲氧基苯酚)∶m(Ni/Al_2O_3-DP)=6∶1。在氧化反应中,探究了氧化条件对反应活性的影响,结果表明:当n(4-甲氧基环己醇)∶n(双氧水)=1.0∶2.5时,353 K反应20 h,目标产物4-甲氧基环己酮的选择性可达95.3%。 相似文献
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以钨酸钠、磷酸、过氧化氢(H_2O_2)和十六烷基三甲基氯化铵为原料制备了过氧磷钨酸季铵盐催化剂。通过FT-IR、TG对催化剂进行了结构和热稳定性的表征。在H_2O_2为氧化剂,无溶剂条件下,采用过氧磷钨酸季铵盐催化α-柏木烯环氧化合成环氧柏木烷。考察了各反应条件对环氧化反应的影响。结果表明,在反应温度60 ℃,反应时间3.5 h,H_2O_2与α-柏木烯摩尔比为1∶2,催化剂过氧磷钨酸季铵盐用量3.0% (以H_2O_2质量计,下同),助剂Na_2HPO_4用量1.6%条件下,环氧柏木烷的收率为65.7%,α-柏木烯的转化率为90.1%,环氧产物选择性可达72.9%。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献