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1.
CuO particles were attempted to fill in the channel of multi-walled carbon nanotubes (MWCNTs) as novel catalytic materials CuO@MWCNTs used for ozonation of humic acids (HA) in aqueous solution.Catalyst samples were characterized by transmission electron microscopy (TEM),X-ray diffraction (XRD),thermogravimetric analysis (TG) and X-ray photoelectron spectroscopy (XPS).The removal efficiency of HA was promoted in the presence of CuO@MWCNTs compared with that of Al2O3-supported CuO catalyst (CuO/Al2O3) and CuO-coating MWCNTs catalyst (CuO/MWCNTs).The strong synergetic effect in the confinement environment on CuO nanoparticles can attribute to the locally higher pressure due to the lower potential energy of reactants in the channels.Strong interaction happened between the catalyst and reactants,which promoted the decomposition of ozone and the generation of OH.The results of experimental and theoretical investigation confirmed that CuO@MWCNTs promotes the initiation and generation of OH,hence accelerating the degradation of organic pollutants.  相似文献   

2.
CuO particles were attempted to fill in the channel of multi-walled carbon nanotubes(MWCNTs)as novel catalytic materials CuO@MWCNTs used for ozonation of humic acids(HA)in aqueous solution.Catalyst samples were characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),thermogravimetric analysis(TG)and X-ray photoelectron spectroscopy(XPS).The removal efficiency of HA was promoted in the presence of CuO@MWCNTs compared with that of Al2 O3-supported CuO catalyst(CuO/Al2O3)and CuO-coating MWCNTs catalyst(CuO/MWCNTs).The strong synergetic effect in the confinement environment on CuO nanoparticles can attribute to the locally higher pressure due to the lower potential energy of reactants in the channels.Strong interaction happened between the catalyst and reactants,which promoted the decomposition of ozone and the generation of OH.The results of experimental and theoretical investigation confirmed that CuO@MWCNTs promotes the initiation and generation of OH,hence accelerating the degradation of organic pollutants.  相似文献   

3.
采用燃烧法制备了Al2O3、CeO2、NiO 金属氧化物改性的CuO-ZnO-ZrO2 催化剂,通过X 射线衍射(XRD)、H2-程序升温还原(H2-TPR)、H2-程序升温脱附(H2-TPD)、CO2-程序升温脱附(CO2-TPD)表征手段,探讨Al2O3、CeO2、NiO 助剂对催化剂物相组成及微观结构的影响,且在固定床连续流动反应装置上考察了添加3种不同助剂对CO2 加氢合成甲醇性能的影响。结果表明,Al2O3、CeO2、NiO 助剂均有助于提高CuO-ZnO-ZrO2 催化剂的活性,且添加适量CeO2 的催化剂催化效果最好;3种助剂都可以抑制CuO 晶粒的生长和提高CuO 的分散度,从而更利于催化剂的还原和H2 的吸附解离;3种金属氧化物助剂均可不同程度地调变催化剂表面碱强度和碱性位数目,较之NiO 改性的催化剂,Al2O3 和CeO2 改性的催化剂表面碱强度更强,碱性位数目也更多,从而更利于CO2 的吸附活化。  相似文献   

4.
采用简单的物理吸附方法制备了高填充率氧化铁@多壁碳纳米管(Fe2O3@MWCNTs)复合材料,并经过正交实验优化获得了制备Fe2O3填充碳纳米管复合材料的最优方案。利用同步热分析仪(DSC-TG)、X射线衍射仪(XRD)、场发射扫描电子显微镜系统(SEM)、场发射透射电子显微分析系统(TEM)等测试手段对复合材料的组分、结构、形貌和填充率进行了表征和分析。结果表明该复合材料中Fe2O3的质量分数为25.79%,TEM结果显示,视野内的大部分碳纳米管内部空腔都填充了Fe2O3,填充的空腔体积约占总空腔体积的90%。  相似文献   

5.
阻燃硅橡胶材料的制备与性能初探   总被引:1,自引:1,他引:0  
分别探讨了氢氧化铝(ATH)/氧化铁、氧化铜、稀土氧化物(ReO)用量对硅橡胶(MMQ)阻燃及力学性能的影响,结果表明:当5.0 g硅橡胶中加入6.0 g氢氧化铝与1.50 g氧化铁时,硅橡胶的阻燃性能较好,但力学性能一般;当硅橡胶中加入5.0 g氢氧化铝与1.25 g氧化铁时,再分别加入少量的氧化铜或稀土氧化物可有效改善硅橡胶的阻燃及力学性能,其最佳用量分别为0.25 g或0.075 g。  相似文献   

6.
采用均匀沉淀包裹法制备了微波诱导催化剂CuO/γ-Al2O3。以活性艳蓝模拟废水为目标降解物,考察了不同制备条件对催化剂活性的影响,并用扫描电镜(SEM)对所制备的催化剂进行了表征。结果表明,在水浴温度为80℃、焙烧温度为200℃、焙烧时间为3h、载体与活性组分摩尔比为2:1、微波烘干4min的条件下,制得的催化剂对活性艳蓝的脱色效果最好,同时将该催化剂用于焦化废水的处理,也获得了较好的处理效果。  相似文献   

7.
以Fe2O3为活性组分,γ—Al2O3为载体,采用浸渍法制备了Fe2O3/Al2O3催化剂,并将其用于催化降解模拟聚丙烯酰胺(PAM)废水考察了催化剂制备条件对催化活性的影响,得出最佳制备工艺条件为:以Fe(NO3)3水溶液为浸渍液、活性组分负载量20%、焙烧时间3h、焙烧温度500℃在温度为60℃、pH=7.0、催化剂加入量为2g/L,H2O2的质量浓度为0.6g/L的条件下对质量浓度为400mg/L聚丙烯酰胺废水进行降解,反应90min后废水中聚丙烯酰胺相对分子质量降解率最高可达90%以上,CODcr去除率达86%,显示出了较高的催化活性.Fe2O3/Al2O3催化剂经过多次重复使用,催化活性基本没有降低,使用寿命长.  相似文献   

8.
采用共沉淀法制备了用于催化湿式氧化工艺的 C u O - Z n O -C e O2 / A l 2O3 催化剂, 采用 X射线衍射 ( XR D)对催化剂进行了表征, 并以实验室配置的苯酚溶液为目标污染物, 考察了C u O - Z n O -C e O2 / A l 2O3催化剂的活性和稳定性。结果表明, C e的加入有提高催化剂体系分散度的作用; 催化剂中的活性组分 C u、 Z n、 C e分别以 C u O、 Z n O、 C e O2的形式存在, 并成功负载于载体 A l 2O3; 对于初始质量浓度为9 0 0m g / L的实验室配置苯酚溶液, 在反应温度为1 8 0℃, 压力为4MP a, 搅拌速度为3 0 0r /m i n, 催化剂加入量为0. 1g /( 1 0 0mL) , 反应时间3 0m i n时, 化学需氧量( COD) 去除率达到9 5%。  相似文献   

9.
用沉积-沉淀和溶胶-凝胶等法在扩孔后的Al2O3基载体上分别制备了不同ZrO2晶相和品粒尺寸的负载型纳米ZrO2/Al2O3复合载体,并用浸渍法制备了Ni/ZrO2/Al2O3.考察了纳米ZrO2品型结构和品粒尺寸对CO2重整CH4催化剂Ni/ZrO2/Al2O3的性能影响.结果表明,四方相ZrO2(t—ZrO2)有利于提高催化剂的表面吸附性能和催化剂的稳定性,同时t-ZrO2晶粒尺寸越小,活性物种的分散度越高,催化剂的活性好.  相似文献   

10.
A pyrotechnical battery is successfully prepared, including an anode and cathode having pyrotechnic charges with Zr, CuO and asbestos. The anode and cathode are separated by a separator formed from LiF, ZrO2, and a fibrous sponge. A digital phosphor oscilloscope (DPO) is used to analyze discharge characterization of the pyrotechnical battery. Then the properties of the electrode materials are characterized by EDS, SEM and a temperature recorder, respectively. The discharge mechanism and safety characteristic are also discussed. The results indicate that the combustion temperature of electrode materials is determined as 1 500.6 ℃ according to thermometry analysis (the case temperature of the battery is lower). The combustion product is identified as ZrO2, Cu2O and Cu by X-ray diffraction (XRD). When the diaphragm is completely melted, Li+ migration and an embedded-based conductive process are formed. Then an electromotive force will immediately reach to the maximum. The discharge performance of the pyrotechnical battery then takes on stability. The electromotive force is up to 2.29 V, and that discharge time continues for more than 18 s. The current density in the small area (less than 2.88 Acm-2) is most effective. The conversion efficiency of electric energy is 96%. The pyrotechnical battery is very safe for the production and use processes.  相似文献   

11.
以Al2O3、SiO2为主体原料,Fe2O3、CuO、Y2O3为辅助原料,经高温烧结合成了适用于谷物干燥的红外辐射陶瓷材料(莫来石及掺杂莫来石)。并测定了其在2.5~15μm波段的红外辐射率在0.845~0.933之间。利用正交实验设计,以红外辐射率为指标进行了配方的优化设计,经过分析得到最佳质量分数的配方方案:主体原料:莫来石子90%(Al2O3与SiO2的摩尔比为3∶2);辅助原料:Fe2O3为2.5%、CuO为5%、Y2O3为2.5%。  相似文献   

12.
以γ-Al2O3,ZrO2,CeO2及复合氧化物Ce0.5Zr0.5O2为催化剂载体,浸渍法负载Cu0制备催化剂.测试了不同载体的Cu0催化剂对CO选择性氧化的反应活性和稳定性.结果表明,催化剂的催化行为与载体的性质密切相关.载体中添加CeO2的催化剂在低温下表现出较好的催化性能.应用XRD,H2-TPR,H2滴定方法表征了催化剂的结构和表面性能.发现活性组分CuO与载体之间有强烈的相互作用.载体CeO2具有持久的供氧能力,使催化剂有优良的抗还原性能,因此表现出了较好的反应活性和稳定性.  相似文献   

13.
Catalytic Wet Air Oxidation process is an efficient measure for treatment of wastewater with great strength which is not biodegradable. Heterocatalysts now become the key investigation subject of catalytic wet air oxidation process due to their good stability and easy separation. In the paper, CuO-SnOE-CeO2/γ-Al2O3 catalysts are prepared by impregnation method, with SnO2 as a doping component, CuO as an active component, CeO2 as a structure stabilizer, γ-Al2O3 as a substrate. XPS test is carried out to investigate the effect of Sn on the chemical surrounding of Cu and O element on the catalyst surface and their catalytic activity. It is shown that the right do-ping of Sn can increase Cu content on the catalyst surface, as a result the quantity of adsorption oxygen is also increased. It is found that Cu content on the catalyst surface is one of the primary factors that determin catalytic activity of catalyst through analyzing the catalytic wet air oxidation process of phenol.  相似文献   

14.
A Sb-Fe-carbon-fiber (CF) composite was prepared by a chemical vapor deposition (CVD) method with in situ growth of CFs us-ing Sb2O3/Fe2O3 as the precursor and acetylene (C2H2) as the carbon source. The Sb-Fe-CF composite was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), and its electrochemical per-formance was investigated by galvanostatic charge-discharge cycling and electrochemical impedance spectroscopy. The Sb-Fe-CF composite shows a better cycling stability than the Sb-amorphous-carbon composite prepared by the same CVD method but using Sb2O3 as the precur-sor. Improvements in cycling stability of the Sb-Fe-CF composite can be attributed to the formation of three-dimensional network structure by CFs, which can connect Sb particles firmly. In addition, the CF layer can buffer the volume change effectively.  相似文献   

15.
采用种子乳液聚合法将Fe2O3超微粒包覆在苯乙烯/丙烯酸/丙烯酸丁酯(St/AA/BA)核-壳型复合共聚物中,形成包覆有无机粒子的有机高分子核-壳型复合微球,从微观的分子尺寸上改变了复合共聚物的性能,并着重研究Fe2O3的含量对这种复合共聚物的动态力学性能的影响。结果表明,随着Fe2O3含量的增加,复合共聚物的内耗明显增加,刚性显著下降。因而Fe2O3加入对复合共聚物有增韧作用,改善了复合共聚物的力学性能。  相似文献   

16.
采用水热合成法制备了SiO2?CeO2载体,并利用浸渍法负载活性组分CuO得到CuO?SiO2?CeO2催化剂。通过XRD、BET和H2?TPR等手段对载体和催化剂进行表征及性能测试,最后探究了SiO2摩尔分数对催化剂的比表面积以及甲醇水蒸气重整制氢实验中催化性能的影响。研究发现,适量添加SiO2可以增加载体和催化剂的比表面积,降低催化剂活性组分CuO的还原温度,提高CH3OH的转化率。当SiO2摩尔分数为2.5%时,催化剂CuO5.0%?SiO22.5%?CeO2的比表面积为112.8 m2/g,CH3OH转化率为75.1%。继续提高催化剂中SiO2的摩尔分数,催化剂的比表面积减小,CH3OH转化率降低。  相似文献   

17.
N2O是循环流化床锅炉产生的主要污染物之一,在循环流化床中,高浓度的循环灰能促进N2O的热分解.本文利用固定床反应器研究了循环灰及其主要组分对N2O热分解的催化作用,实验结果表明,循环灰对N2O热分解的催化作用与循环灰的组成和比表面积分布有关.循环灰中的Al2O3,CaO,Fe2O3和Fe3O4是促进N2O热分解的活性成分,能促进N2O的热分解,循环灰的比表面积也是影响其对N2O热分解催化能力的重要因素.在循环灰作用下,N2O热分解会通过副反应生成少量的NO.  相似文献   

18.
CuO—Al混合粉末微波加热至一定温度下可发生内氧化反应,用X射线衍射仪对反应后的复合粉末进行成份分析,确定CuO-Al混合粉末发生内氧化反应的最佳温度与时间。在此条件下采用常规烧结方法制备Al2O3/Cu复合材料。SEM分析表明,微波内氧化法可以有效制备Al2O3/Cu复合材料,细小的Al2O3增强相弥散分布在Al2O3/Cu复合材料中。  相似文献   

19.
Fenton reaction based on Fe2+-H2O2 system has been widely applied in water remediation, but the obvious drawbacks largely hinder its practical uses. Alternatively, heterogeneous nanomaterials with proper surface modification could be used as Fenton-like catalysts. Surface doping of Ti O2 could concentrate the pollutants surrounding the Fe3O4 catalyst, which might benefit the catalytic performance of Fe3O4. Herein, we reported that Ti O2-doped Fe3O4 nanoparticles(NPs) could be used as high-performance Fenton-like catalyst for dye decoloration in near neutral environment, where the doping of Ti O2 on Fe3O4 surface dramatically improved the catalytic activity of Fe3O4 in Fenton-like reaction. Ti O2-doped Fe3O4 NPs catalyzed the decomposition of H2O2 to oxidize methylene blue without external energy supply, resulting in effective decoloration. Ti O2-doped Fe3O4 NPs showed high catalytic activity under various p H values and even in the presence of radical scavenger. More catalysts and H2O2 would facilitate the decoloration. At higher temperature, the decoloration became faster and more effective. The implication to the environmental applications of Ti O2-doped Fe3O4 NPs is discussed.  相似文献   

20.
Three-dimensional hierarchical Co3O4 microstructures decorated with Ag and Cu oxides were prepared via displacement reaction and subsequent annealing treatment. Photocatalytic properties measurements revealed that the photocatalystic activities of CuO/Co3O4 composites (Co3O4 microstructures decorated with CuO) were enhanced while those of Ag2O/Co3O4 composites (Co3O4 microstructures decorated with Ag2O) were reduced, when compared with those of pure hierarchical Co3O4 microstructures toward the degradation of methyl orange. In addition, CuO/Co3O4 composites exhibited an excellent recyclability ability of photodegradation. The electrochemical properties test indicated that both of the composite oxide electrodes exhibited excellent pseudocapacitive performance with relatively high specific capacitance and good long-term cycling stability. With the increase of the loaded Ag2O and CuO dosages deposited on the Co3O4 microstructures surface, the specific capacitance values of the composites were increased. Ag2O/Co3O4 composite electrodes showed higher specific capacitance values and better cycling stability than CuO/Co3O4 composite ones.  相似文献   

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