C307型中低压甲醇合成催化剂的工业应用

简述了德士古水煤浆气化工艺流程及设备,介绍了C307型甲醇合成催化剂的物化性能及装填情况,主要介绍了该催化剂在兖矿鲁南化肥厂的前期使用情况,并对使用结果进行了评价,C307甲醇合成催化剂低温活性好、选择性好、低还原收缩率、副产物少,经济效益显著。     

全球甲醇工业生产现状与发展趋势

综述甲醇工业技术现状,分析目前国内外甲醇工业的生产发展情况,未来3～5a国内甲醇装置将供过于求,建议控制国内甲醇装置建设过热的势头,提出加快甲醇下游生物产品的开发步伐.     

清液体系中高性能T型沸石分子筛膜的合成

由摩尔组成为SiO2:Al2O3:Na2O:K2O:H2O=1:0.015:0.25:0.08:25的澄清溶液,在预涂晶种的管状莫来石支撑体上水热合成T型沸石分子筛膜.在高于100℃清液体系中合成出了高性能T型沸石分子筛膜.用X射线衍射(X-ray diffraction,XRD)仪和扫描电子显微镜(scanning electron microscope,SEM)对150℃下合成35 h的分子筛膜进行了表征.XRD谱表明:T型沸石分子筛成功地生长在预涂晶种的支撑体上.支撑体的外表面覆盖着20 μm厚有取向的晶体层.从SEM照片判断,起到分离作用的是生长致密的中间层,而不是表层.在150℃下制备的膜,对水/乙醇、水/异丙醇混合物具有高渗透汽化分离性能.优异的渗透汽化性能归因于在涂有晶种的多孔支撑体上生长了一层高结晶度且缺陷较少的T型沸石分子筛晶体层.     

ZrO2 和Al2O3支撑的MFI 型沸石分子筛膜:支撑体材料对膜性能的影响

采用水热合成法，以纯SiO2为源物质，在介孔Y2O3掺杂的ZrO2(YZ)及大孔α-Al2O3支撑体上制备出高质量的MFI型沸石分子筛膜，通过H2／n-C4H10气体混合物的渗透分离和p-xylene的蒸发研究了不同支撑体上MFI型沸石分子筛膜分离性能，在较低温度范围，YZ支撑的MFI型沸石分子筛膜中n-C4H10的渗透率比Al2O3支撑的膜高很多，最大n-C4H10与H2的分离率达到500，Al2O3支撑的膜中py-xylene的蒸发流量随时间下降很快，而YZ支撑的膜中的蒸发流量则变化缓慢，用XRD对膜的晶体结构进行分析，通过多种温度下热处理不同支撑体上的膜样品研究了其热稳定性与支持体材料的关系，YZ支撑的MFI型沸石分子筛膜的MFI结构在1000摄氏度后仍能保持，而Al2O3支撑的膜950摄氏度时已完全转变为石英相，研究结果表明，YZ支撑的MFI型沸石分子筛膜比Al2O3支撑的膜表现出更好的厌不性，热稳定性以及抗阻塞性。     

Heterogeneously assisted oxidation of adsorbates from carbonmonoxide, methanol and ethanol by hydrogen peroxide solutions on platinum electrodes in sulphuric acid

The influence of hydrogen peroxide on the adsorption and oxidation of carbon monoxide, methanol and ethanol adlayers on porous Pt electrodes were studied in 2 M sulphuric acid solution by means of cyclic voltammetry and differential electrochemical mass spectrometry (DEMS). The oxidation of adsorbed species is observed at electrode potentials far less negative than those required for electrochemical adsorbate oxidation. The oxidation by H₂O₂ is dependent on its concentration in solution, as well as on the adsorbates and their coverages. In all cases the isolated adlayers are oxidised by dissolved H₂O₂. However, the presence of H₂O₂ during adsorption partially inhibits adlayer formation from CH₃OH and C₂H₅OH, but avoids almost completely the adsorption of carbon monoxide. The removal of the residues from the surface by dissolved hydrogen peroxide probably occurs through O_ad species formed during the heterogeneous decomposition reaction of H₂O₂ on Pt.     

Electrooxidation of methanol at platinum–ruthenium catalysts prepared from colloidal precursors: Atomic composition and temperature effects

The electrocatalytic oxidation of methanol was investigated on PtRu electrodes of different atomic compositions at several temperatures (from 25 to 110 °C). Very active catalyst nanoparticles supported on active carbon (Vulcan XC 72) were obtained using the colloidal synthesis developed by Bönnemann et al. [11], allowing easy variation of the atomic composition. These electrocatalysts were characterized by TEM, EDX and XRD; results indicate that they consist of platinum nanoparticles decorated by ruthenium. Methanol oxidation was studied as a function of composition, temperature and methanol concentration. Two effects were investigated: the effect of the working temperature and the effect of the atomic composition. It appeared that for lower methanol electrooxidation overvoltages, the best catalysts are ruthenium-rich, whereas at higher overvoltages the best one is the Pt + Ru (80:20)/C composition, irrespective of the working temperature, either in half-cell or in a single DMFC.     

A highly stable and efficient catalyst for direct synthesis of LPG from syngas

Liquefied petroleum gas (LPG) fuel was directly synthesized from syngas over a hybrid catalyst which contained a methanol synthesis catalyst and zeolite. The new hybrid catalyst composed of (Pd–Ca/SiO₂) and β-zeolite, showed a high activity and selectivity for LPG production. X-ray diffraction (XRD) characterization of the catalyst was used to analyze the deactivation of (Pd–Ca/SiO₂)/β-zeolite.     

甲醇市场分析及发展甲醇工业应注意的问题

分析和预测了国内外甲醇消费用户目前和今后几年的需求情况,从新建装置的布局、产品深加工、生产成本和市场价格等方面提出了发展甲醇工业应注意的问题。     

浅论燃料甲醇的前景

我国今后的能源结构中,煤化工将扮演越来越重要的角色。引用大量数据说明燃料甲醇是一种新型车用燃料,燃料甲醇可充分利用国内的现有单醇、联醇装置生产能力。燃料甲醇的应用市场开发具有现实意义,并提出一些建议。     

On the nature of the active state of silver during catalytic oxidation of methanol

Under the applied high reaction temperatures (900 K) the Ag surface is restructured and a tightly held oxygen species is formed on the surface (O) apart from O atoms dissolved in the bulk (O). Methanol oxidation to formaldehyde proceeds through this O species as demonstrated by application of a variety of spectroscopic techniques.