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1.
氨分解得到的H 2不含CO x 、SO x 、NO x 等有害物质,是其他所有含碳资源为原料制氢所不能比拟的。本文采用无模板水热法制备了一系列棒状载体,并采用沉积沉淀法制备了Ru/La x Ce 1-x O y 催化剂,考察了制备方法、催化剂组成对性能的影响,并通过扫描电镜(SEM)、X射线衍射(XRD)、BET、H 2-程序升温还原(TPR)和CO 2-程序升温脱附(TPD)进行了表征。结果表明,La 2O 3掺杂量为40%的Ru/La 0.4Ce 0.6O 1.8催化剂在常压、7800h -1、450℃下氨分解转化率为98%。该催化剂活性高归因于部分还原的CeO 2-x 对Ru的供电子性能和Ru/La 0.4Ce 0.6O 1.8催化剂表面的强碱性增加了对Ru活性位的给电子能力。同时考察了K 2O含量的影响,最优的催化剂为Ru-2%K/La 0.4Ce 0.6O 1.8,在400℃、7800h -1氨气转化率可以达到93%。结果表明Ru-2%K/La 0.4Ce 0.6O 1.8可以作为一种新型高效氨分解催化剂,为工业化应用提供了可能,具有良好的发展前景。 相似文献
2.
The perovskite-type oxides La 0.8Ce 0.2Cu 0.4Mn 0.6O 3 and La 0.8Ce 0.2Ag 0.4Mn 0.6O 3 prepared by reverse microemulsion and sol–gel methods (denoted as R and S, respectively), have been investigated on their catalytic performance for the (NO + CO) reaction, and characterized by means of temperature-programmed desorption (TPD), X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). XRD measurements proved the presence of the perovskite phase with a considerable amount of CeO 2 phase and the formation of CeO 2 phase was restrained with the reverse microemulsion method. TEM investigations revealed that the La 0.8Ce 0.2Cu 0.4Mn 0.6O 3-R nanoparticles were uniform spheres in shape with diameters ranging from 40 to 50 nm, whereas an aggregation of particles was found for the La 0.8Ce 0.2Cu 0.4Mn 0.6O 3-S catalyst. The activity of NO reduction with CO decreased in the order of La 0.8Ce 0.2Cu 0.4Mn 0.6O 3-R > La 0.8Ce 0.2Cu 0.4Mn 0.6O 3-S > La 0.8Ce 0.2Ag 0.4Mn 0.6O 3-R > La 0.8Ce 0.2Ag 0.4Mn 0.6O 3-S. In NO-TPD experiments, the principal desorbed species detected in the effluent was NO with a trace amount of O 2 and N 2O, suggesting that the non-dissociated adsorption of NO on the surface of the perovskite-type oxides was dominant. The XPS results revealed that Ce 4+ and Cu + was the predominant oxidation state for Ce and Cu components in La 0.8Ce 0.2Cu 0.4Mn 0.6O 3 and La 0.8Ce 0.2Ag 0.4Mn 0.6O 3 catalysts. The existence of Cu + ions and its redox reaction (Cu + ↔ Cu 2+) would benefit the NO adsorption and reduction by CO. 相似文献
3.
The catalytic combustion of the emission from coke ovens containing various volatile organic compounds (VOCs) and inorganic species over a La 0.9Ce 0.1CoO 3 catalyst is investigated in an integral fixed reactor through several steps. (1) Combustion of a mixture of VOC reveals that the kinetics of total oxidation of methane determines the total VOC conversion. (2) The conversion of methane, in the case of sulfur-free feed is inhibited by H 2O and CO 2. 相似文献
4.
Direct nitric oxide decomposition over perovskites is fairly slow and complex, its mechanism changing dramatically with temperature. Previous kinetic study for three representative compositions (La 0.87Sr 0.13Mn 0.2Ni 0.8O 3−δ, La 0.66Sr 0.34Ni 0.3Co 0.7O 3−δ and La 0.8Sr 0.2Cu 0.15Fe 0.85O 3−δ) has shown that depending on the temperature range, the inhibition effect of oxygen either increases or decreases with temperature. This paper deals with the effect of CO 2, H 2O and CH 4 on the nitric oxide decomposition over the same perovskites studied at a steady-state in a plug-flow reactor with 1 g catalyst and total flowrates of 50 or 100 ml/min of 2 or 5% NO. The effect of carbon dioxide (0.5–10%) was evaluated between 873 and 923 K, whereas that of H 2O vapor (1.6 or 2.5%) from 723 to 923 K. Both CO 2 and H 2O inhibit the NO decomposition, but inhibition by CO 2 is considerably stronger. For all three catalysts, these effects increase with temperature. Kinetic parameters for the inhibiting effects of CO 2 and H 2O over the three perovskites were determined. Addition of methane to the feed (NO/CH 4=4) increases conversion of NO to N 2 about two to four times, depending on the initial NO concentration and on temperature. This, however, is still much too low for practical applications. Furthermore, the rates of methane oxidation by nitric oxide over perovskites are substantially slower than those of methane oxidation by oxygen. Thus, perovskites do not seem to be suitable for catalytic selective NO reduction with methane. 相似文献
5.
Effect of additives, In 2O 3, SnO 2, CoO, CuO and Ag, on the catalytic performance of Ga 2O 3–Al 2O 3 prepared by sol–gel method for the selective reduction of NO with propene in the presence of oxygen was studied. As for the reaction in the absence of H 2O, CoO, CuO and Ag showed good additive effect. When H 2O was added to the reaction gas, the activity of CoO-, CuO- and Ag-doped Ga 2O 3–Al 2O 3 was depressed considerably, while an intensifying effect of H 2O was observed for In 2O 3- and SnO 2-doped Ga 2O 3–Al 2O 3. Of several metal oxide additives, In 2O 3-doped Ga 2O 3–Al 2O 3 showed the highest activity for NO reduction by propene in the presence of H 2O. Kinetic studies on NO reduction over In 2O 3–Ga 2O 3–Al 2O 3 revealed that the rate-determining step in the absence of H 2O is the reaction of NO 2 formed on Ga 2O 3–Al 2O 3 with C 3H 6-derived species, whereas that in the presence of H 2O is the formation of C 3H 6-derived species. We presumed the reason for the promotional effect of H 2O as follows: the rate for the formation of C 3H 6-derived species in the presence of H 2O is sufficiently fast compared with that for the reaction of NO 2 with C 3H 6-derived species in the absence of H 2O. Although the retarding effect of SO 2 on the activity was observed for all of the catalysts, SnO 2–Ga 2O 3–Al 2O 3 showed still relatively high activity in the lower temperature region. 相似文献
6.
Catalytic performance of Sn/Al 2O 3 catalysts prepared by impregnation (IM) and sol–gel (SG) method for selective catalytic reduction of NO x by propene under lean burn condition were investigated. The physical properties of catalyst were characterized by BET, XRD, XPS and TPD. The results showed that NO 2 had higher reactivity than NO to nitrogen, the maximum NO conversion was 82% on the 5% Sn/Al 2O 3 (SG) catalyst, and the maximum NO 2 conversion reached nearly 100% around 425 °C. Such a temperature of maximum NO conversion was in accordance with those of NO x desorption accompanied with O 2 around 450 °C. The activity of NO reduction was enhanced remarkably by the presence of H 2O and SO 2 at low temperature, and the temperature window was also broadened in the presence of H 2O and SO 2, however the NO x desorption and NO conversion decreased sharply on the 300 ppm SO 2 treated catalyst, the catalytic activity was inhibited by the presence of SO 2 due to formation of sulfate species (SO 42−) on the catalysts. The presence of oxygen played an essential role in NO reduction, and the activity of the 5% Sn/Al 2O 3 (SG) was not decreased in the presence of large oxygen. 相似文献
7.
Different bulk metal oxides (NiO, CuO, Mn 2O 3, Cr 2O 3 and Co 3O 4) were prepared and tested for the combustion of methane–air lean mixtures (5000 ppmV of CH 4) in presence of SO 2 (40 ppmV). Methane combustion experiments were carried out at ambient pressure, 425 and 625 °C and a space time of 93.3 g h mol CH4−1. Catalysts aged (60 h on stream) both in absence and in presence of SO 2, were characterised by nitrogen physisorption (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), temperature-programmed desorption (TPD-MS) and infrared spectroscopy (DRIFTS). It was observed that Cr 2O 3 is not deactivated at the studied conditions, whereas all the other materials present fast deactivation in presence of SO 2. Aged catalysts characterisation reveals that the outstanding behaviour of the Cr 2O 3 catalyst is caused by the absence of formation of surface sulphates. By contrast, Mn 2O 3 and Co 3O 4 are more active than Cr 2O 3 for methane oxidation in absence of sulphur species, but they are strongly deactivated in presence of SO 2. Finally, the performance of the Cr2O3 catalysts was compared to the corresponding to Pd/Al2O3 catalyst and to a highly sulphur-tolerant perovskite (La0.9Ce0.1CoO3) for the oxidation of methane in a real industrial emission from a coke oven, containing different inorganic gases (NH3, N2, H2, H2O, CO, CO2, SO2 and H2S). Cr2O3 catalyst shows to be also the most stable catalyst for the treatment of these emissions. 相似文献
8.
CH 4/CO 2 reforming over La 2NiO 4 and 10%NiO/CeO 2–La 2O 3 catalysts under the condition of supersonic jet expansion was studied via direct monitoring of the reactants and products using the sensitive technique of cavity ring-down spectroscopy. Vibration–rotational absorption lines of CH 4, H 2O, CO 2 and CO molecules were recorded in the near infrared spectral region. Our results indicated that La 2NiO 4 is superior to 10%NiO/CeO 2–La 2O 3 in performance. In addition, we observed enhanced reverse-water-gas-shift reaction at augmented reaction temperature. The formation of reaction intermediates was also investigated by means of time-of-flight mass spectrometry and there was the detection of CH x+, OH + and H + species. 相似文献
9.
The role of La 2O 3 loading in Pd/Al 2O 3-La 2O 3 prepared by sol–gel on the catalytic properties in the NO reduction with H 2 was studied. The catalysts were characterized by N 2 physisorption, temperature-programmed reduction, differential thermal analysis, temperature-programmed oxidation and temperature-programmed desorption of NO. The physicochemical properties of Pd catalysts as well as the catalytic activity and selectivity are modified by La2O3 inclusion. The selectivity depends on the NO/H2 molar ratio (GHSV = 72,000 h−1) and the extent of interaction between Pd and La2O3. At NO/H2 = 0.5, the catalysts show high N2 selectivity (60–75%) at temperatures lower than 250 °C. For NO/H2 = 1, the N2 selectivity is almost 100% mainly for high temperatures, and even in the presence of 10% H2O vapor. The high N2 selectivity indicates a high capability of the catalysts to dissociate NO upon adsorption. This property is attributed to the creation of new adsorption sites through the formation of a surface PdOx phase interacting with La2O3. The formation of this phase is favored by the spreading of PdO promoted by La2O3. DTA shows that the phase transformation takes place at temperatures of 280–350 °C, while TPO indicates that this phase transformation is related to the oxidation process of PdO: in the case of Pd/Al2O3 the O2 uptake is consistent with the oxidation of PdO to PdO2, and when La2O3 is present the O2 uptake exceeds that amount (1.5 times). La2O3 in Pd catalysts promotes also the oxidation of Pd and dissociative adsorption of NO mainly at low temperatures (<250 °C) favoring the formation of N2. 相似文献
10.
Combined effect of H 2O and SO 2 on V 2O 5/AC the activity of catalyst for selective catalytic reduction (SCR) of NO with NH 3 at lower temperatures was studied. In the absence of SO 2, H 2O inhibits the catalytic activity, which may be attributed to competitive adsorption of H 2O and reactants (NO and/or NH 3). Although SO 2 promotes the SCR activity of the V 2O 5/AC catalyst in the absence of H 2O, it speeds the deactivation of the catalyst in the presence of H 2O. The dual effect of SO 2 is attributed to the SO 42− formed on the catalyst surface, which stays as ammonium-sulfate salts on the catalyst surface. In the absence of H 2O, a small amount of ammonium-sulfate salts deposits on the surface of the catalyst, which promote the SCR activity; in the presence of H 2O, however, the deposition rate of ammonium-sulfate salts is much greater, which results in blocking of the catalyst pores and deactivates the catalyst. Decreasing V 2O 5 loading decreases the deactivation rate of the catalyst. The catalyst can be used stably at a space velocity of 9000 h −1 and temperature of 250 °C. 相似文献
11.
Reduction behavior of pure and doped CeO 2, the multi-phase La 0.6Sr 0.4CoO 3? xCeO 2, La 0.8Sr 0.2MnO 3 ? xCeO 2, and La 0.95Ni 0.6Fe 0.4O 3? xCeO 2 composites, was studied under hydrogen containing atmosphere to address issues related to the improvement of electrochemical and catalytic performance of electrodes in fuel cells. The enhanced reduction of cerium oxide was observed initially at 800°C in all composites in spite of the presence of highly reducible transition metal cations that could lead to the increase in surface concentration of oxygen vacancies and generation of the electron enriched surface. Due to continuous reduction of cerium oxide in La 0.6Sr 0.4CoO 3? xCeO 2 and La 0.8Sr 0.2MnO 3? xCeO 2 (up to 10 h) composites the redox activity of the Ce 4+/Ce 3+ pair could be suppressed and additional measures are required for reversible spontaneous regeneration of Ce 4+. After 3 h exposure to H 2-Ar at 800°C the reduction of cerium oxides and perovskite phases in La 0.95Ni 0.6Fe 0.4O 3? xCeO 2 composites was diminished. The extent of cerium oxide involvement in the reduction process varies with time, and depends on its initial deviation from oxygen stoichiometry (that results in the larger lattice parameter and the longer pathway for O 2- transport through the fluorite lattice), chemical origin of transition metal cations in the perovskite, and phase diversity in multi-phase composites. 相似文献
12.
Ag-modified La 0.6Sr 0.4MnO 3-based catalysts with the perovskite-type structure were prepared by using a citric acid sol–gel method, and their catalytic performance for complete oxidation of methanol and ethanol was evaluated and compared with that of the γ-Al 2O 3-supported catalysts, Ag/γ-Al 2O 3, Pt/γ-Al 2O 3, and Pd/γ-Al 2O 3. The results showed that the Ag-modified La 0.6Sr 0.4MnO 3-based catalysts with the perovskite-type structure displayed the activity significantly higher than that of the supported precious metal catalysts, 0.1%Pd/γ-Al 2O 3 and 0.1%Pt/γ-Al 2O 3 in the temperature range of 370–573 K. Over a 6%Ag/20%La 0.6Sr 0.4MnO 3/γ-Al 2O 3 catalyst, the T95 temperature for methanol oxidation can be as low as 413 K. Even at such low reaction temperature, there were little HCHO and CO detected in the reaction exit-gas. However, for the 0.1%Pd/γ-Al 2O 3 and 0.1%Pt/γ-Al 2O 3 catalysts, the HCHO content in the reaction exit-gas reached 200 and 630 ppm at their T95 temperatures. Over a 6%Ag/La 0.6Sr 0.4MnO 3 catalyst, the T95 temperature for ethanol oxidation can be as low as 453 K, with a corresponding content of CH 3CHO in the exit-gas at 782 ppm; when ethanol oxidation is performed at 493 K, the content of acetaldehyde in the exit-gas can be below 1 ppm. Characterization of the catalysts by X-ray diffraction (XRD), TEM, XPS, laser Raman spectra (LRS), hydrogen temperature-programmed reduction (H 2-TPR) and oxygen temperature-programmed desorption (O 2-TPD) methods revealed that both the surface and the bulk phase of the perovskite La 0.6Sr 0.4MnO 3 played important roles in the catalytic oxidation of the alcohols, and that γ-Al 2O 3 as the bottom carrier could be beneficial in creating a large surface area of catalyst. Moreover, a small amount of Ag + doped onto the surface of La 0.6Sr 0.4MnO 3 was able to partially occupy the positions of La 3+ and Sr 2+ due to their similar ionic radii, and thus, became stabilized by the perovskite lattice, which would be in favor of preventing the aggregation of the Ag species on the surface and enhancing the stability of the catalyst. On the other hand, modification of the Ag + to the surface of La 0.6Sr 0.4MnO 3 resulted in an increase in relative content of the surface O 22−/O − species highly reactive toward the alcohols and aldehydes as well as CO. Besides, solution of low-valence metal oxides SrO and Ag 2O with proper amounts in the lattice of the trivalent metal perovskite-type oxide LaMnO 3 would also lead to an increase in the content of the reducible Mn n+ and the formation of anionic vacancies, which would be favorable for the adsorption-activation of oxygen on the functioning catalyst and the transport of the lattice and surface oxygen species. All these factors would contribute to the pronounced improvement of the catalyst performance. 相似文献
13.
采用自行研究设计的介质阻挡-电晕放电等离子体反应装置在模拟烟气中进行NO、SO 2的脱除研究。考察了O 2、CO 2、水蒸气等气体组分对脱除NO、SO 2的影响,并进一步探讨了添加剂CH 3COONH 4对脱除NO、SO 2的影响及作用机理。实验结果表明:O 2、CO 2和水蒸气浓度的增加对NO脱除有抑制作用,而引入CH 3COONH 4后,这些抑制作用会被减弱,使NO的脱除率得到大幅度提升,但这些抑制作用不会完全消除。在引入CH 3COONH 4后,气体组分和输入电流的变化对脱除SO 2的影响不明显,SO 2脱除率可达到94%左右。在N 2/O 2/CO 2/H 2O/NO/SO 2体系中加入0.27%的CH 3COONH 4后,NO初始浓度不变的条件下,SO 2含量较少时,对NO的脱除影响不明显,随着SO 2浓度的增加,NO的脱除率不断下降,增加CH 3COONH 4的添加量可消除SO 2的影响;另一方面,在SO 2初始浓度恒定的条件下,随着NO含量的增加,SO 2的脱除率保持在94%左右。在N 2/O 2/CO 2/H 2O/NO/SO 2体系中加入0.51%的CH 3COONH 4后,输入电流2.5A时,NO的脱除率达到72%。 相似文献
14.
Catalytic reduction of NO by propene in the presence of oxygen was studied over SnO 2-doped Ga 2O 3–Al 2O 3 prepared by sol–gel method. Although SnO 2-doped Ga 2O 3–Al 2O 3 gave lower NO conversion than Ga 2O 3–Al 2O 3 in the absence of H 2O, the activity was enhanced considerably by the presence of H 2O and much higher than that of Ga 2O 3–Al 2O 3. The presence of SnO 2 and Ga 2O 3–Al 2O 3 species having intimate Ga–O–Al bondings was found to be essential for the promotional effect of H 2O. The promotional effect of H 2O was interpreted by the following two reasons. The first one is the removal of carbonaceous materials deposited on the catalyst surface by H 2O. The other is the selective inhibition by H 2O of the reaction steps resulting in propene oxidation to CO x without reducing NO. 相似文献
15.
采用自行设计的介质阻挡耦合电晕放电等离子体反应装置进行了模拟烟气同时脱硫脱硝的研究,分别考察乙醇胺(HOCH 2CH 2NH 2,MEA)在不同模拟烟气体系中对NO、SO 2脱除的影响,深入探讨了MEA在放电过程中与NO的作用机理。结果表明:在N 2/O 2/SO 2/NO体系中,0.56% MEA的加入可以显著消除O 2对NO脱除的抑制作用;在N 2/CO 2/SO 2/NO体系中,MEA会吸收进入体系中的部分CO 2,以减弱CO 2对NO脱除的抑制;在N 2/O 2/CO 2/H 2O/NO/SO 2体系中,0.56% MEA的加入既可以有效减弱H 2O的影响,也可以使NO的脱除率达到71.28%,继续将MEA的体积分数增大至1.20%时,可将该体系下NO脱除率提高到81.25%;同时,MEA可以在短时间内高效吸收体系内的SO 2,且几乎不受其他气体成分的影响,SO 2脱除率保持在95%左右。 相似文献
16.
The catalytic behavior in N 2O reduction by propane in the presence of O 2, H 2O and SO 2 of Fe/ZSM-5 catalysts prepared by ion exchange and chemical vapour deposition (CVD) is reported. The catalyst prepared by CVD shows a lower dependence of the rate of selective N 2O reduction on the decrease in C 3H 8 to N 2O ratio in the feed and a higher resistance to deactivation by SO 2 in accelerated durability tests with high SO 2 concentration (500 ppm). This catalyst shows stable catalytic behavior in the presence of SO 2 for more than 600 h of time-on-stream. Characterization of the catalysts by UV–VIS–NIR diffuse reflectance indicates that the poor performances of the sample prepared by ion exchange could be related to the presence of highly clustered Fe 3+ species, in this catalyst. On the other hand, Fe 2O 3 particles are not present in the sample prepared by CVD while mainly isolated Fe 3+ ions and iron-oxide nanoclusters are present. 相似文献
17.
A comparative analysis of perovskite structured cathode materials, La 0.65Sr 0.35MnO 3 (LSM), La 0.8Sr 0.2CoO 3 (LSC), La 0.6Sr 0.4FeO 3 (LSF) and La 0.6Sr 0.4Co 0.2Fe 0.8O 3 (LSCF), was performed for a ceramic-carbonate nanocomposite fuel cell using composite electrolyte consisting of Gd 0.1Ce 0.9O 1.95 (GDC) and a eutectic mixture of Na 2CO 3 and Li 2CO 3. The compatibility of these nanocomposite electrode powder materials was investigated under air, CO 2 and air/CO 2 atmospheres at 550 °C. Microscopy measurements together with energy dispersive X-ray spectroscopy (EDS) elementary analysis revealed few spots with higher counts of manganese relative to lanthanum and strontium under pure CO 2 atmosphere. Furthermore, electrochemical impedance (EIS) analysis showed that LSC had the lowest resistance to oxygen reduction reaction (ORR) (14.12 Ω·cm 2) followed by LSF (15.23 Ω·cm 2), LSCF (19.38 Ω·cm 2) and LSM (>300 Ω·cm 2). In addition, low frequency EIS measurements (down to 50 µHz) revealed two additional semi-circles at frequencies around 1 Hz. These semicircles can yield additional information about electrochemical reactions in the device. Finally, a fuel cell was fabricated using GDC/NLC nanocomposite electrolyte and its composite with NiO and LSCF as anode and cathode, respectively. The cell produced an excellent power density of 1.06 W/cm 2 at 550 °C under fuel cell conditions. 相似文献
18.
In this contribution, a commercial spherical SiO 2 was modified with different amounts of La 2O 3, and used as the support of Ni catalysts for autothermal reforming of methane in a fluidized-bed reactor. Nitrogen adsorption, XRD and H 2-TPR analysis indicated that La 2O 3-modified SiO 2 had higher surface area, strengthened interaction between Ni and support, and improved dispersion of Ni. CO 2-TPD found that La 2O 3 increased the alkalescence of SiO 2 and improved the activation of CO 2. Coking reaction (via both temperature-programmed surface reaction of CH 4 (CH 4-TPSR) and pulse decomposition of CH 4) disclosed that La 2O 3 reduced the dehydrogenation ability of Ni. CO 2-TPO, O 2-TPO (followed after CH 4-TPSR) confirmed that only part amount of carbon species derived from methane decomposition could be removed by CO 2, and O 2 in feed played a crucial role for the gasification of the inactive surface carbons. Ni/ xLa 2O 3-SiO 2 ( x = 10, 15, 30) possessed high activity and excellent stability for autothermal reforming of methane in a fluidized-bed reactor. 相似文献
19.
Novel, hierarchical, flower-like Ag/Cu 2O and Au/Cu 2O nanostructures were successfully fabricated and applied as efficient electrocatalysts for the electrochemical reduction of CO 2. Cu 2O nanospheres with a uniform size of ~180 nm were initially synthesized. Thereafter, Cu 2O was used as a sacrificial template to prepare a series of Ag/Cu 2O composites through galvanic replacement. By varying the Ag/Cu atomic ratio, Ag 0.125/Cu 2O, having a hierarchical, flower-like nanostructure with intersecting Ag nanoflakes encompassing an inner Cu 2O sphere, was prepared. The as-prepared Ag x/Cu 2O samples presented higher Faradaic efficiencies (FE) for CO and relatively suppressed H 2 evolution than the parent Cu 2O nanospheres due to the combination of Ag with Cu 2O in the former. Notably, the highest CO evolution rate was achieved with Ag 0.125/Cu 2O due to the larger electroactive surface area furnished by the hierarchical structure. The same hierarchical flower-like structure was also obtained for the Au 0.6/Cu 2O composite, where the FE CO (10%) was even higher than that of Ag 0.125/Cu 2O. Importantly, the results reveal that Ag 0.125/Cu 2O and Au 0.6/Cu 2O both exhibit remarkably improved stability relative to Cu 2O. This study presents a facile method of developing hierarchical metal-oxide composites as efficient and stable electrocatalysts for the electrochemical reduction of CO 2. 相似文献
20.
以改性活性炭为载体,采用等体积浸渍法制备了La 2O 3/AC催化剂。采用XRD和BET手段对催化剂进行表征,使用微型固定床反应器考察催化剂的脱硫脱硝活性。结果表明,La 2O 3/AC催化剂对CO同时还原SO 2和NO具有良好活性,负载质量分数10%的La 2O 3/AC催化剂活性较好,SO 2和NO转化率达到90%的反应温度最低,分别为335 ℃和325 ℃;载体与活性组分之间存在协同作用,引入活性炭载体能够降低反应温度并提高催化活性。 相似文献
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