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21.
DJ—3新型塔盘在催化重整脱水塔中的应用 总被引:1,自引:0,他引:1
对新型DJ-3复合塔盘的性能进行了简介,简述了重整蒸馏脱水过程及特点,重点突出蒸馏脱水塔的扩能改造,总结了DJ-3复合塔盘的工业应用及生产标定情况。 相似文献
22.
As a renewable feedstock and due to its high functionality glycerol is an attractive reactant for the production of a large number of valuable compounds. We report on an environmentally friendly alternative to produce chemicals from the glycerol oxidation, which are currently produced either by stoichiometric oxidation processes or by enzymatic routes. We investigate the heterogeneously catalyzed liquid-phase oxidation of glycerol with carbon supported gold catalysts. The prepared nanosized gold catalysts are highly active, so that the reaction could be performed under atmospheric pressure. The influence of the preparation method of the catalysts has been investigated. Moreover, the support effect on the catalytic process has been studied and discussed in terms of pore structure of the investigated carbon materials. The promotor effect of platinum on Au/C catalysts was examined and it could be shown that the presence of Pt increases not only the catalyst activity but also the selectivity. By promoting the gold catalysts with platinum the selectivity to dihydroxyacetone could be increased from 26% (Au/C) to 36% (Au–Pt/C). 相似文献
23.
24.
The combined use of calorimetric and catalytic methods for the investigation of the acid-base properties of oxide systems is discussed with reference to the authors' work on pure and doped zirconia samples, ceria-zirconia and ceria-lanthana solid solutions. Adsorption microcalorimetry of ammonia and carbon dioxide had been used to characterize the samples, whose chemical and thermal history was taken into account. The catalytic behavior of these samples in the conversion of 4-methylpentan-2-ol, route to 4-methylpent-1-ene (starting product for the manufacture of polymers of superior technological properties), had also been studied. On the basis of the calorimetric data, a rationale for interpreting the data for the transformation of 4-methylpentan-2-ol is formulated, which takes into account the role of the concentration and strength of the sites in governing the competition among the various mechanisms for dehydration and dehydrogenation. 相似文献
25.
介绍了微波干燥的原理和主要特点,研究了利用微波辐射干燥氟化铝工艺,探讨了微波功率、微波辐射时间、物料质量、物料厚度对氟化铝脱水率的影响。实验的最佳条件为微波功率2.0kW、干燥时间80s、物料质量400g、物料厚度2.0cm。实验结果表明,利用微波辐射干燥,氟化铝含水质量分数小于1%,且干燥时间短、能耗低,实验为工业化提供了必要的参考数据。 相似文献
26.
以聚丙烯酰胺类药剂为主要原料,通过改性合成FY高效污泥脱水剂.通过原料的筛选,不同反应条件的考察,获得最佳工艺条件.将合成得到的产品与进口药剂进行了污泥脱水效果的比较.实验证明,FY药剂不论是在处理效果上还是在成本上都达到了国外药剂的水平,并且药剂经复配后有更强的适用性. 相似文献
27.
The separation performance of two different commercially available tubular inorganic membranes was studied for solvent dehydration. The separation layers consisted of A-type zeolite and microporous silica. The membrane characteristics were determined as function of operating conditions such as feed composition, temperature, and permeate pressure in pervaporation and vapor permeation. Among different membranes of the same batch, flux and selectivity were reproducible within 10%. The partial flux of water as the preferentially permeating component increases linearly with the water vapor pressure difference between feed and permeate and depends only marginally (viscosity influence) upon the properties of the organic component. The flux of the organic (retained) component is low and can best be described by assuming a substance and membrane specific permeance (flux over partial pressure difference) that is independent of composition. At very low water concentration in the feed one would expect a strong increase in permeability of the retained component through non-zeolite pores and larger silica pores as predicted by pure component measurements. However, this effect was not observed in mixtures within the concentration range studied here. A temperature rise improves flux rates exponentially while selectivity remains high. Thus, higher module cost in comparison to polymeric membranes can be compensated by reduced membrane area if a higher operating temperature can be chosen. Flux and selectivity decline as a function of permeate pressure with decreasing driving force. In vapor permeation with inorganic membranes superheating of the vaporous feed improves their performance while for polymeric materials a steep flux decline is observed. High flux and selectivity are obtained in the separation of water from alcohols. The normalized flux values of the A-type zeolite membrane are roughly 10 kg/m2 h bar with a mixture selectivity of 2000 for methanol, 4000 for ethanol and 8000 for n-butanol. The average permeance of the amorphous silica membrane lies above 12 kg/m2 h bar with mixture selectivity of 50 for methanol, 500 for ethanol and 2000 for n-butanol. The separation mechanism is mainly based on adsorption and diffusion enhanced by shape selectivity and size exclusion in some cases. The transport characteristics could be described with a simple transport model based on normalized permeate fluxes. With regard to the operation stability of the membranes, no deterioration of the performance was observed for the A-type zeolite in solvent dehydration or in separation of water from reaction mixtures. The silica membrane showed an initial conditioning effect involving a rearrangement of Si-OH groups with an increase in selectivity and decrease in flux of about 30%. After a few hours the performance stabilized and remained constant during further operation. 相似文献
28.
本文文综述了中老油田采出液性质的变化和高含水采出液的油水分离特性,探讨了聚醚型破乳剂和高分子破乳剂在高含水采出液状况下的适应性。通过理论分析和大庆两个联合站的现场实验证明,高分子破乳剂特别适用于高含水采出液的事实,并指出了其适应性和提出了其质量与适应性的评价方法。 相似文献
29.
Thomas Onfroy Guillaume Clet Saeed B. Bukallah David M. Hercules Marwan Houalla 《Catalysis Letters》2003,89(1-2):15-19
A series of NbO
x
/ZrO2 catalysts containing up to 2.67wt Nb (ca. 80 nominal surface coverage) was prepared by incipient wetness impregnation from niobium oxalate and oxalic acid solution. The structure of the catalysts was monitored by X-ray diffraction and Raman spectroscopy. The results indicated the presence of a surface Nb phase. No evidence for the formation of crystalline Nb2O5 species was found. The development of the acidity as a function of Nb loading was monitored by adsorption of a basic probe molecule followed by infrared spectroscopy. The results indicated the appearance of Brnsted acid sites for a threshold of Nb loading. The abundance of Brnsted acid sites correlated well with the isopropanol dehydration activity. The overall behavior was very similar to that reported earlier for the WO
x
/ZrO2 system. 相似文献
30.
P.D. Francis 《臭氧:科学与工程》1987,9(4):369-390
Organic contaminants dissolved in deionized pretreated and raw mains water were reacted with ultraviolet light and ozone. Ozone first was used for partial oxidation followed by ozone combined with ultraviolet radiation to produce total oxidation. The reduction of TOC level and direct oxidation of halogenated compounds were measured throughout the treatment process. The rate of TOC reduction was compared for ozone injected upstream and inside the reactor. 相似文献