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1.
The oxidation of CH 4 over Pt–NiO/δ-Al 2O 3 has been studied in a fluidised bed reactor as part of a major project on an autothermal (combined oxidation–steam reforming) system for CH 4 conversion. The kinetic data were collected between 773 and 893 K and 101 kPa total pressure using CH 4 and O 2 compositions of 10–35% and 8–30%, respectively. Rate–temperature data were also obtained over alumina-supported monometallic catalysts, Pt and NiO. The bimetallic Pt–NiO system has a lower activation energy (80.8 kJ mol −1) than either Pt (86.45 kJ mol −1) and NiO (103.73 kJ mol −1). The superior performance of the bimetallic catalyst was attributed to chemical synergy. The reaction rate over the Pt–NiO catalyst increased monotonically with CH 4 partial pressure but was inhibited by O 2. At low partial pressures (<30 kPa), H 2O has a detrimental effect on CH 4 conversion, whilst above 30 kPa, the rate increased dramatically with water content. 相似文献
2.
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
3.
The effect of SO 2 addition on the oxidation of ethyl acetate, ethanol, propane and propene, over Pt/γ-Al 2O 3 and Pt/SiO 2 has been investigated. The reactants (300–800 vol. ppm) were mixed with air and led through the catalyst bed. The conversions below and above light-off were recorded both in the absence and in the presence of 1–100 vol. ppm SO 2. For the alumina-supported catalyst, the conversion of ethyl acetate, ethanol and propane was promoted by the addition of SO 2, while the conversion of propene was inhibited. The effect of SO 2 was reversible, i.e. the conversion of the reactants returned towards the initial values when SO 2 was turned off. However, this recovery was quite slow. The oxidation of propane was inhibited by water, both in absence and presence of SO 2. For the silica-supported catalyst no significant effect of SO 2 could be observed on the conversion of ethyl acetate, ethanol or propane, whereas the conversion of propene was inhibited by the presence of SO 2. In situ FTIR measurements revealed the presence of surface sulphates on the Pt/γ-Al 2O 3 catalyst with and after SO 2 addition. It is proposed that these sulphate groups enhance the oxidation of propane, ethyl acetate and ethanol by creating additional reaction pathways to Pt on the surface of the Pt/γ-Al 2O 3 catalyst. 相似文献
4.
Two types of NiO/γ-Al 2O 3 catalysts prepared by the impregnation and the sol–gel method were used for the partial oxidation of methane to syngas at 850°C (GHSV1.8×10 5 lkg −1 h −1). The effects of the carbon deposition, the loss and sintering of nickel and the phase transformation of γ-Al 2O 3 support on the catalytic performance during 80 h POM reaction were investigated with a series of characterization such as XRD, BET, AAS, TG, and XPS. The results indicated that the carbon deposition and the loss and sintering of nickel could not cause the serious decrease of catalytic performance over NiO/γ-Al 2O 3 catalyst during the short-time reaction. However, the slow process of the support γ-Al 2O 3 phase transforming into -Al 2O 3 could slowly decrease the performance of NiO/γ-Al 2O 3 catalysts. Aimed at the reasons of the deactivation, an improved catalyst was obtained by the complexing agent-assisted sol–gel method. 相似文献
5.
通过等体积浸渍法制备单贵金属Pt/γ-Al 2O 3和双金属Pt-Ce/γ-Al 2O 3催化剂,考察Ce对催化剂活性的影响,确定催化剂最优配比。结果表明,当Pt的负载量为质量分数0.5%时,Pt/γ-Al 2O 3催化活性最高;当Pt的负载量为质量分数0.2%,Ce的负载量为质量分数1.0%时,Pt-Ce/γ-Al 2O 3催化剂的催化活性最高。Pt-Ce/γ-Al 2O 3催化剂的甲苯转化率高于Pt/γ-Al 2O 3催化剂。随着Pt负载量增大,催化剂孔容、孔径减小。粉体式催化剂性能优于整体式催化剂,但差别不大;Ce的添加有助于催化剂活性的提升。 相似文献
6.
Mn effect and characterization on γ-Al 2O 3-, -Al 2O 3- and SiO 2-supported Ru catalysts were investigated for Fischer–Tropsch synthesis under pressurized conditions. In the slurry phase Fischer–Tropsch reaction, γ-Al 2O 3 catalysts showed higher performance on CO conversion and C 5+ selectivity than -Al 2O 3 and SiO 2 catalysts. Moreover, Ru/Mn/γ-Al 2O 3 exhibited high resistance to catalyst deactivation and other catalysts were deactivated during the reaction. From characterization results on XRD, TPR, TEM, XPS and pore distribution, Ru particles were clearly observed over the catalysts, and γ-Al 2O 3 catalysts showed a moderate pore and particle size such as 8 nm, where -Al 2O 3 and SiO 2 showed highly dispersed ruthenium particles. The addition of Mn to γ-Al 2O 3 enhanced the removal of chloride from RuCl 3, which can lead to the formation of metallic Ru with moderate particle size, which would be an active site for Fischer–Tropsch reaction. Concomitantly, manganese chloride is formed. These schemes can be assigned to the stable nature of Ru/Mn/γ-Al 2O 3 catalyst. 相似文献
7.
In this work, different procedures, namely carbonate coprecipitation and modified solid–solid diffusion, were used to prepare hexaaluminate samples, unsupported or supported onto θ-Al 2O 3. These samples were used as catalyst for the methane total oxidation as synthesized or after impregnation of 1 wt% Pd. It was observed that the modified solid–solid diffusion procedure is an efficient method to obtain the hexaaluminate structure. At a theoretical ratio x of hexaaluminate onto Al 2O 3 less than 0.6 ( xLa 0.2Sr 0.3Ba 0.5MnAl 11O 19 + (1− x)·Al 2O 3, with x = 0.25, 0.60), samples with high specific surface area and θ-Al 2O 3 structure are then obtained. Large differences in catalytic activity can be observed among the series of sample synthesized. All the pure oxide samples (i.e. without palladium) present low catalytic activity for methane total oxidation compared to a reference Pd/Al 2O 3 catalyst. The highest activity was obtained for the samples presenting a θ-Al 2O 3 structure (with x = 0.60) and a high surface area. Impregnation of 1 wt% palladium resulted in an increase in catalytic activity, for all the solids synthesized in this work. Even if the lowest light-off temperature was obtained on the reference sample, similar methane conversions at high temperature (700 °C) were obtained on the stabilized θ-Al 2O 3 solids ( x = 0.25, 0.60). Moreover, the reference sample is found to strongly deactivate with reaction time at the temperature of test (700 °C), due to a progressive reduction of the PdO x active phase into the less active Pd° phase, whereas excellent stabilities in reaction were obtained on the pure and palladium-doped hexaaluminate and supported θ-Al 2O 3 samples. This clearly showed the beneficial effect of the support for the stabilization of the PdO x active phase at high reaction temperature. These properties are discussed in term of oxygen transfer from the support to the palladium particle. Oxygen transfer is directly related to the Mn 3+/Mn 2+ redox properties (in the case of the hexaaluminate and stabilized θ-Al 2O 3 samples), that allows a fast reoxidation of the metal palladium sites since palladium sites reoxidation cannot occur directly by gaseous dioxygen adsorption and dissociation on the surface. 相似文献
8.
A method to quantify DRIFT spectral features associated with the in situ adsorption of gases on a NO x adsorber catalyst, Pt/K/Al 2O 3, is described. To implement this method, the multicomponent catalyst is analysed with DRIFT and chemisorption to determine that under operating conditions the surface comprised a Pt phase, a pure γ-Al 2O 3 phase with associated hydroxyl groups at the surface, and an alkalized-Al 2O 3 phase where the surface –OH groups are replaced by –OK groups. Both DRIFTS and chemisorption experiments show that 93–97% of the potassium exists in this form. The phases have a fractional surface area of 1.1% for the 1.7 nm-sized Pt, 34% for pure Al 2O 3 and 65% for the alkalized-Al 2O 3. NO 2 and CO 2 chemisorption at 250 °C is implemented to determine the saturation uptake value, which is observed with DRIFTS at 250 °C. Pt/Al 2O 3 adsorbs 0.087 μmol CO 2/m 2and 2.0 μmol NO 2/m 2, and Pt/K/Al 2O 3 adsorbs 2.0 μmol CO 2/m 2and 6.4 μmol NO 2/m 2. This method can be implemented to quantitatively monitor the formation of carboxylates and nitrates on Pt/K/Al 2O 3 during both lean and rich periods of the NO x adsorber catalyst cycle. 相似文献
9.
A fixed-bed reactor was utilized to investigate the activities of six metal catalysts (1% Pt, 1% Pd, 1% Ru, 5% Co, 5% Mo and 5% W on γ-Al 2O 3 support) in decomposing naphthalene, based on the production of carbon dioxide and the disappearance of naphthalene. The Pt and Pd catalysts were found to exhibit higher naphthalene oxidizing activity than other catalysts tested. The Co catalysts, whose activity is similar to that of the Ru catalysts, are promising for naphthalene oxidation. The kinetic results of naphthalene oxidation over 1% Pt/γ-Al 2O 3 catalysts are reported for the first time. A first-order reaction with respect to Pnaphthalene was found, while the reaction order with respect to PO2 decreased with increasing reaction temperatures. A Langmuir–Hinshelwood model was used to describe the observed kinetic behavior. Oxygen adsorption dominates at higher reaction temperatures (>140 °C), and consequently the oxidation of naphthalene over the Pt catalysts appeared to be insensitive to PO2. 相似文献
10.
H 3PMo 12O 40 catalyst was chemically immobilized on the surface modified CMK-3 (SM-CMK-3) support as a charge compensating component, by taking advantage of the overall negative charge of [PMo 12O 40] 3−. The supported H 3PMo 12O 40/SM-CMK-3 catalyst was characterized to have high surface area (≈1000 m 2/g) and relatively large pore volume (0.83 cm 3/g). The H 3PMo 12O 40/SM-CMK-3 catalyst was applied to the vapor-phase 2-propanol conversion reaction. The H 3PMo 12O 40/SM-CMK-3 catalyst exhibited higher 2-propanol conversion than the unsupported H 3PMo 12O 40 and the impregnated H 3PMo 12O 40 on CMK-3. Furthermore, the PMo 12/SM-CMK-3 catalyst showed the enhanced oxidation activity (acetone formation) and the suppressed acid catalytic activity (propylene formation) compared to the other two catalysts. It is believed that [PMo 12O 40] 3− species were chemically and finely immobilized on the SM-CMK-3 support as charge matching species, and thus, the PMo 12/SM-CMK-3 catalyst showed an excellent oxidation activity. 相似文献
11.
Time-resolved FT-IR spectra of CO oxidation over Pt/Al 2O 3 catalysts were collected in situ in transmission mode under transient reaction conditions. Using the step-scan acquisition mode of a commercial FT-IR spectrometer, time-resolution of a few milliseconds, compared to several hundred milliseconds in the normal rapid-scan mode, could be achieved. The experiments were triggered by reproducible oxygen gas pulses at constant temperature. Infrared light transmission, uniform heating and fast gas exchange were realized by pressing the pure catalyst powder onto a thin stainless steel wire mesh using a low volume reaction cell. By comparing the results of both acquisition modes, rapid-scan and step-scan, we will demonstrate, that it is possible, in a rather simple way, to investigate heterogeneously catalysed reactions under reaction conditions by means of FT-IR spectroscopy with time-resolutions down to a few milliseconds, and, in principle, lower. CO oxidation between 443 and 573 K over 1%Pt/γ-Al 2O 3 and 4%Pt/γ-Al 2O 3 catalysts has been investigated as a test reaction. By using the high time-resolution of the step-scan acquisition mode we could obtain new details of the dynamics of the CO oxidation reaction over a supported Pt catalyst at high temperatures and 1 atm pressure. 相似文献
12.
Dispersing La 2O 3 on δ- or γ-Al 2O 3 significantly enhances the rate of NO reduction by CH 4 in 1% O 2, compared to unsupported La 2O 3. Typically, no bend-over in activity occurs between 500° and 700°C, and the rate at 700°C is 60% higher than that with a Co/ZSM-5 catalyst. The final activity was dependent upon the La 2O 3 precursor used, the pretreatment, and the La 2O 3 loading. The most active family of catalysts consisted of La 2O 3 on γ-Al 2O 3 prepared with lanthanum acetate and calcined at 750°C for 10 h. A maximum in rate (mol/s/g) and specific activity (mol/s/m 2) occurred between the addition of one and two theoretical monolayers of La 2O 3 on the γ-Al 2O 3 surface. The best catalyst, 40% La 2O 3/γ-Al 2O 3, had a turnover frequency at 700°C of 0.05 s −1, based on NO chemisorption at 25°C, which was 15 times higher than that for Co/ZSM-5. These La 2O 3/Al 2O 3 catalysts exhibited stable activity under high conversion conditions as well as high CH 4 selectivity (CH 4 + NO vs. CH 4 + O 2). The addition of Sr to a 20% La 2O 3/γ-Al 2O 3 sample increased activity, and a maximum rate enhancement of 45% was obtained at a SrO loading of 5%. In contrast, addition of SO =4 to the latter Sr-promoted La 2O 3/Al 2O 3 catalyst decreased activity although sulfate increased the activity of Sr-promoted La 2O 3. Dispersing La 2O 3 on SiO 2 produced catalysts with extremely low specific activities, and rates were even lower than with pure La 2O 3. This is presumably due to water sensitivity and silicate formation. The La 2O 3/Al 2O 3 catalysts are anticipated to show sufficient hydrothermal stability to allow their use in certain high-temperature applications. 相似文献
13.
A multi-component NO x-trap catalyst consisting of Pt and K supported on γ-Al 2O 3 was studied at 250 °C to determine the roles of the individual catalyst components, to identify the adsorbing species during the lean capture cycle, and to assess the effects of H 2O and CO 2 on NO x storage. The Al 2O 3 support was shown to have NO x trapping capability with and without Pt present (at 250 °C Pt/Al 2O 3 adsorbs 2.3 μmols NO x/m 2). NO x is primarily trapped on Al 2O 3 in the form of nitrates with monodentate, chelating and bridged forms apparent in Diffuse Reflectance mid-Infrared Fourier Transform Spectroscopy (DRIFTS) analysis. The addition of K to the catalyst increases the adsorption capacity to 6.2 μmols NO x/m 2, and the primary storage form on K is a free nitrate ion. Quantitative DRIFTS analysis shows that 12% of the nitrates on a Pt/K/Al 2O 3 catalyst are coordinated on the Al 2O 3 support at saturation. When 5% CO2 was included in a feed stream with 300 ppm NO and 12% O2, the amount of K-based nitrate storage decreased by 45% after 1 h on stream due to the competition of adsorbed free nitrates with carboxylates for adsorption sites. When 5% H2O was included in a feed stream with 300 ppm NO and 12% O2, the amount of K-based nitrate storage decreased by only 16% after 1 h, but the Al2O3-based nitrates decreased by 92%. Interestingly, with both 5% CO2 and 5% H2O in the feed, the total storage only decreased by 11%, as the hydroxyl groups generated on Al2O3 destabilized the K–CO2 bond; specifically, H2O mitigates the NOx storage capacity losses associated with carboxylate competition. 相似文献
14.
The catalytic oxidation of unsymmetrical dimethylhydrazine (UDMH) by air has been studied in a vibro-fluidized catalyst bed laboratory kinetic setup over catalysts Cu xMg 1−xCr 2O 4/γ-Al 2O 3, 32.9%Ir/γ-Al 2O 3 and β-Si 3N 4 in a temperature range 150–400 °C. The catalyst Cu xMg 1−xCr 2O 4/γ-Al 2O 3 was found to be optimal regarding high yields of CO 2 and low yields of NO x. A probable mechanism of UDMH heterogeneous catalytic oxidation is proposed. Catalyst Cu xMg 1−xCr 2O 4/γ-Al 2O 3 has been further used in the pilot plant specially designed for the destruction of UDMH. Results of testing the main fluidized bed catalytic reactor for UDMH oxidation and the reactor for selective catalytic reduction of NO x with NH 3 are presented. These results prove that the developed UDMH destruction technology is highly efficient and environmentally safe. 相似文献
15.
以γ-Al 2O 3为载体,采用等体积分步浸渍法制备了以Ni为活性组分,La、Ce、Fe、Cr、Co为助剂的催化剂M/γ-Al 2O 3,在固定床管式反应器中研究了M/γ-Al 2O 3催化剂的性能,考察了反应温度、水碳比和空速对氢产率的影响,并对催化剂进行XRD、SEM和BET表征。结果表明,NiLaCeFeCrCo/γ-Al 2O 3催化剂具有较好的催化性能,在反应温度700 ℃、水碳物质的量比10和空速6 min -1的条件下,氢产率达到27.335 mol·mol -1,并在300 min内表现出较好的活性,平均氢产率为21.966 mol·mol -1。 相似文献
16.
The influences of calcination temperatures and additives for 10 wt.% Cu/γ-Al 2O 3 catalysts on the surface properties and reactivity for NO reduction by C 3H 6 in the presence of excess oxygen were investigated. The results of XRD and XPS show that the 10 wt.% Cu/γ-Al 2O 3 catalysts calcined below 973 K possess highly dispersed surface and bulk CuO phases. The 10 wt.% Cu/γ-Al 2O 3 and 10 wt.% Mn–10 wt.% Cu/γ-Al 2O 3 catalysts calcined at 1073 K possess a CuAl 2O 4 phase with a spinel-type structure. In addition, the 10 wt.% La–10 wt.% Cu/γ-Al 2O 3 catalyst calcined at 1073 K possesses a bulk CuO phase. The result of NO reduction by C 3H 6 shows that the CuAl 2O 4 is a more active phase than the highly dispersed and bulk CuO phase. However, the 10 wt.% Mn–10 wt.% Cu/γ-Al 2O 3 catalyst calcined at 1073 K possesses significantly lower reactivity for NO reduction than the 10 wt.% Cu/γ-Al 2O 3 catalyst calcined at 1073 K, although these catalysts possess the same CuAl 2O 4 phase. The low reactivity for NO reduction for 10 wt.% Mn–10 wt.% Cu/γ-Al 2O 3 catalyst calcined at 1073 K is attributed to the formation of less active CuAl 2O 4 phase with high aggregation and preferential promotion of C 3H 6 combustion to CO x by MnO 2. The engine dynamometer test for NO reduction shows that the C 3H 6 is a more effective reducing agent for NO reduction than the C 2H 5OH. The maximum reactivity for NO reduction by C 3H 6 is reached when the NO/C 3H 6 ratio is one. 相似文献
17.
The NO-H 2-O 2 reaction was studied over supported bimetallic catalysts, Pt-Mo and Pt-W, which were prepared by coexchange of hydrotalcite-like Mg-Al double layered hydroxides by Pt(NO 2) 42−, MoO 42−, and/or WO 42− and subsequent heating at 600 °C in H 2. The Pt–Mo interaction could obviously be seen when the catalyst after reduction treatment was exposed to a mixture of NO and H 2 in the absence of O 2. The Pt-HT catalyst showed the almost complete NO conversion at 70 °C, whereas the Pt-Mo-HT showed a negligible conversion. Upon exposure to O 2, however, Pt-Mo-HT exhibited the NO conversion at the lowest temperature of ≥30 °C, compared to ≥60 °C required for Pt-HT. EXAFS/XANES, XPS and IR results suggested that the role of Mo is very sensitive to the oxidation state, i.e., oxidized Mo species residing in Pt particles are postulated to retard the oxidative adsorption of NO as NO 3 and promote the catalytic conversion of NO to N 2O at low temperatures. 相似文献
18.
A new catalyst composed of nickel oxide and cerium oxide was studied with respect to its activity for NO reduction by CO under stoichiometric conditions in the absence as well as the presence of oxygen. Activity measurements of the NO/CO reaction were also conducted over NiO/γ-Al 2O 3, NiO/TiO 2, and NiO/CeO 2 catalysts for comparison purposes. The results showed that the conversion of NO and CO are dependent on the nature of supports, and the catalysts decreased in activity in the order of NiO/CeO 2 > NiO/γ-Al 2O 3 > NiO/TiO 2. Three kinds of CeO 2 were prepared and used as support for NiO. They are the CeO 2 prepared by (i) homogeneous precipitation (HP), (ii) precipitation (PC), and (iii) direct decomposition (DP) method. We found that the NiO/CeO 2(HP) catalyst was the most active, and complete conversion of NO and CO occurred at 210 °C at a space velocity of 120,000 h −1. Based on the results of surface analysis, a reaction model for NO/CO interaction over NiO/CeO 2 has been proposed: (i) CO reduces surface oxygen to create vacant sites; (ii) on the vacant sites, NO dissociates to produce N 2; and (iii) the oxygen originated from NO dissociation is removed by CO. 相似文献
19.
Monodispersed nano-Au/γ-Al 2O 3 catalysts for low-temperature oxidation of CO have been prepared via a modified colloidal deposition route, which involves the deposition of dodecanethiolate self-assembled monolayer (SAM)-protected gold nanoparticles (C 12 nano-Au) in hexane on γ-Al 2O 3 at room temperature. The diameter of the gold nanoparticles deposited on the support is 2.5 ± 0.8 nm after thermal treatment, and their valence states comprise both the metallic and oxidized states. It is found that the thermal treatment temperature affects significantly the catalytic activity of the catalysts in the processing steps. The catalyst treated at 190 °C exhibits considerably higher activity as compared to catalysts treated at 165 and 250 °C. A 2.0-wt.% nano-Au/γ-Al 2O 3 catalyst treated at 190 °C for 15 h maintains the catalytic activity at nearly 100% CO oxidation for at least 800 h at 15 °C, at least 600 h at 0 °C, and even longer than 450 h at −5 °C. Evidently, the catalysts obtained using this preparation route show high catalytic activity, particularly at low temperatures, and a good long-term stability. 相似文献
20.
Fuel cells are recognized as the most promising new power generation technology, but hydrogen supply is still a problem. In our previous work, we have developed a LiLaNiO/γ-Al 2O 3 catalyst, which is excellent not only for partial oxidation of hydrocarbons, but also for steam reforming and autothermal reforming. However, the reaction needs pure oxygen or air as oxidant. We have developed a dense oxygen permeable membrane Ba 0.5Sr 0.5Co 0.8Fe 0.2O 3 which has an oxygen permeation flux around 11.5 ml/cm 2 min at reaction conditions. Therefore, this work is to combine the oxygen permeable membrane with the catalyst LiLaNiO/γ-Al 2O 3 in a membrane reactor for hydrogen production by mixed reforming of heptane. Under optimized reaction conditions, a heptane conversion of 100%, a CO selectivity of 91–93% and a H 2 selectivity of 95–97% have been achieved. 相似文献
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