共查询到20条相似文献,搜索用时 78 毫秒
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醋酸混合溶剂中碘催化甲烷部分氧化过程研究 总被引:6,自引:0,他引:6
在醋酸和杂多酸混和溶剂中进行了甲烷液相部分氧化过程研究.进行了碘系列催化剂以及溶剂体系中杂多酸筛选,考察了催化剂用量、磷钨酸浓度、氧化剂类型、反应温度、压力等条件对甲烷转化的影响.结果表明,在磷钨酸浓度0.072 mol/L,碘含量0.04 mol/L,KMnO4为0.158 mol/L,温度210℃,压力4.0 Mpa条件下,甲烷转化率可达12.98%,目的产物醋酸甲酯选择性84.39%.初步探讨了醋酸和磷钨酸混合溶剂中碘催化甲烷液相选择性氧化的亲电反应机理. 相似文献
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用于甲烷选择性氧化反应制甲醇的膜催化技术 总被引:5,自引:0,他引:5
朱立忠 《化学工业与工程技术》1997,18(1):11-14
研究了将甲烷选择性地一次氧化制取甲醇的膜催化技术。采用ZrO2-Y2O3陶瓷膜,在较温和的反应条件下(常压,460℃左右),可以将甲烷选择性地一次氧化成为甲醇。 相似文献
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The catalytic partial oxidation of methane to syngas (CO H2) has been simulated thermodynamically with the advanced process simulator PRO/Ⅱ. The influences of temperature,pressure,CH4/O2 ratio and steam addition in feed gas on the conversion of CH4 selectively to syngas and heat duty required were investigated, and their effects on carbon formation were also discussed. The simulation results were in good agreement with the literature data taken from a spouted bed reactor. 相似文献
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采用常规的浸渍法制备镍基催化剂,研究了甲烷空气催化部分氧化制备含氮合成气的催化性能,得到了镍含量在8%时部分氧化活性最佳;加入镧助剂使催化剂的活性和选择性达到95.3%和97.5%,通过向体系加入H2O和CO2,可以提高加压条件下甲烷的转化率并抑制催化剂积炭,可以获得n(H2):n(CO)接近2的合成气;催化剂连续使用500h性能稳定。 相似文献
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采用常规的浸渍法制备了镍基催化剂和经过镧改性的镍基催化剂,研究了甲烷催化部分氧化制备含氮合成气的催化功能,结果说明,镍含量在8%时催化活性达到最好,同时加入镧进行改性后催化剂的活性和选择性有所提高;该催化剂对甲烷空气催化部分氧化制合成气在常压下具有较高的转化率,随压力升高,转化率明显下降,并且积极严重,通过向体系加入H2O和CO2可以提高加压条件下甲烷的转化率并抑制催化剂积碳,还可以获得H2/CO接近2的合成气,满足合成液体燃料的要求。 相似文献
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Methane‐air partial oxidation to methanol over a ceramic‐supported Fe2O3‐CuO catalyst was investigated in a post‐plasma catalytic reactor at ambient conditions. The multicomponent catalyst exerted a better catalytic performance than the monocomponent Fe2O3 catalyst. Characterization of the catalysts by XPS showed that incorporation of the CuO additive to a Fe2O3‐based catalyst resulted in an increase of lattice oxygen in the surface of the catalyst which facilitated selective methane oxidation. Hydrogen temperature‐programmed reduction revealed that addition of the CuO promoter could improve the reduction performance of the catalyst. Moreover, this catalyst showed excellent stability and resistance against carbon deposition in the extended reactions while maintaining catalytic activity. A post‐plasma catalytic mechanism is proposed with three main pathways to methanol synthesis. 相似文献
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The partial oxidation of methane to synthesis gas over Ni/α‐Al2O3 catalysts (1 and 5 wt.‐% Ni loading, 71–160 and 250–355 μm particle diameter) was investigated in different types of fluidized‐bed reactors, i.e., the bubbling fluidized bed (FlB), the spout fluid bed (SFB) and the internally circulating fluidized bed (ICFB). A methane‐to‐oxygen ratio of 2:1 was used in all experiments and the temperature was varied between 700 and 800 °C. Gas velocities and catalyst masses were adjusted to assure a stable and controllable reactor operation. A nearly isothermal operation was established in all reactors. The thermodynamic equilibrium values were achieved in the FlB and SFB reactor whereas in the ICFB reactor slightly lower conversions and selectivities were obtained. Taking the direct scale‐up concept of the ICFB reactor into account, significant higher space‐time yields were obtained in this reactor than in the industrial‐scale bubbling fluidized‐bed reactor. No increase of the space‐time yield in comparison to the FlB was obtained in the SFB reactor. 相似文献
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Ahmed I. Osman 《化学工程与技术》2020,43(4):641-648
The multifunctional potential of a transition and noble metal catalyst supported on either a single support or combined oxide support in the catalytic partial oxidation of methane (CPOM) is reviewed. The close interaction and interfacial area between the metal, reducible oxide, and acidic support are highlighted, which are crucial for low-temperature CPOM. The effects of the catalyst components and their preparation methods are considered. Their impact on the catalytic performance and stability on the CPOM reaction is evaluated. The two main mechanisms of CPOM, namely, direct partial oxidation and combustion and reforming reaction, are also covered along with the most recent kinetic studies. Finally, the deactivation of the CPOM catalysts is evaluated in terms of coke and carbon deposition along with CO poisoning. 相似文献
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Direct-methane solid oxide fuel cells were used to produce electricity and syngas. During initial operation at 750 °C, the
cells produced 0.9 W/cm2 and ≈90% methane conversion to syngas at a rate of 30 sccm/cm2. However, the methane conversion decreased continuously over the first 30–40 h of operation, even though the solid oxide
fuel cells (SOFC) electrical performance was stable. An additional catalyst layer on the anode yielded more stable methane
conversion to syngas. 相似文献
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甲烷部分氧化制合成气反应的研究 总被引:3,自引:0,他引:3
用粒度为5mm的α-Al2O3、β-Al2O3、γ-Al2O3为载体,用浸渍法制备了10%(质量)Ni基催化剂。在固定床流动反应器中,在反应温度500-850℃,大空速和不同的CH4/O2摩尔比下,测定了该催化剂用于甲烷部分氧化制合成气的活性和CO选择性。500℃用H2对催化剂还2h后,进行活性测试结果,10%Ni/β-Al2O3、Ni/γ-Al2O3对POM反应无活性,只有10%Niα-Al2O3对POM反应有活性。TPR测试结果表明,这是由于10%Ni/β-Al2O3和Ni/γ-Al2O3催化剂在700℃以下未被还原所致。另外,合成气的生成速率和CO选择尾均随反应温度和空速的增大而增大,并在CH4/O2摩尔比2时有最大值。 相似文献
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SCR烟气脱硝过程中SO2和SO3的测量 总被引:1,自引:0,他引:1
建立了同时测量烟气中SO2和SO3浓度的测量方法.采用三级收集系统对气体中的SO2进行收集,并采用离子色谱仪对吸收液中的SO3^2-和SO4^2-扣进行测量,以确定待测气体中SO2和S03的浓度.该方法测量SO2和SO2的误差分别为1.2%和-29.6%.采用该方法对自行制备的V2O5/WO3/TiO2催化荆催化还原NO和催化氧化SO2的情况进行了研究.实验结果表明,脱硝率和SO2氧化率均随反应温度升高而增加.综合考虑脱硝和SO2氧化问题,最佳的烟气脱硝温度区间为310℃~400℃.烟气中的NH3和NO与SO2在催化剂表面竞争吸附,降低了SO2氧化率. 相似文献