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烷烃异构化是提高汽油辛烷值的重要方法。叙述了C5C6烷烃异构化催化剂的研究现状,介绍双功能催化剂、超强固体酸催化剂以及离子液体催化剂,幵阐述不同金属活性组分、助剂添加剂、载体对异构化催化剂性能的影响。最后对异构化催化剂的収展趋势进行展望,以期为新型C5C6异构化催化剂的研収及应用提供新的思路和借鉴。 相似文献
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介绍国内首套40万t·a-1 C5/C6低温异构化装置的工艺技术特点及标定情况。首套引进C5/C6低温异构化装置成功运行,使反应产物辛烷值提高15个单位,对汽油质量升级具有重要意义。 相似文献
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轻质烷烃异构化技术是满足汽油质量升级要求的重要工艺路线。以某炼厂异构化固定床反应装置为研究对象,将异构化汽油划分为10个集总并建立反应网路,同时以实际生产数据为基础进行了动力学参数计算,并建立了HYSYS平推流速率反应器的稳态模型。利用此模型对异构化装置关键操作参数与产品性质的平衡关系进行灵敏度分析,为异构化反应器操作调整提供科学的理论指导。并制定了装置优化方案,即继续采用一次通过流程,调节反应器运行温度至130.4℃后与重整油按比例调和后去下游装置,或通过稳定分离单元将部分低辛烷值单甲基戊烷循环至反应器,提高后续异构化汽油辛烷值。 相似文献
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轻质正构烷烃异构化是油田液态烃加工利用的重要手段,也是炼厂提高汽油轻质馏分辛烷值的重要方法。为适应环境保护的要求,异构化工艺将发挥越来越重要的作用。因此,受到人们的普遍重视。本文从工艺和催化剂两方面,综述了近年来研究工作的进展,分析了异构化技术未来的发展趋势。 相似文献
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Etherification of two alkenes, 2-methyl-1-butene and 2,4,4-trimethyl-1-pentene, was studied with seven different C1- to C4-alcohols. Although etherification was of primary interest, the isomerisation of the alkenes was the main reaction to occur. For the primary alcohols the etherification and isomerisation rates correlated well with the properties of the alcohols. Both rates increased with decreasing polarity and with increasing carbon number, acidity and Mulliken charge of the oxygen atom of the alcohol. It is difficult to distinguish the effect of each property separately, and probably the differences in the reactivities are not due to any one property alone but rather the synergy of the properties affects the reactivities. The secondary alcohols behaved in a different way than the primary ones: the etherification was almost negligible. The effect of alcohol on the isomerisation of alkenes was notable even though alcohol does not directly react in the reaction, which was concluded to be due to the stronger adsorption of the more polar alcohols which hinders the reactions of other components. 相似文献
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The effect of addition of tin on the catalytic activity of Ru/C catalysts has been investigated in the liquid phase hydrogenation of -methylstyrene and hydrocinnamaldehyde. On increasing the Sn content, the amount of CO chemisorbed decreases, indicating a decrease in the number of Ru surface atoms. In the hydrogenation of -methylstyrene the specific activity of Ru (calculated per Ru surface atom) remains constant regardless of the Sn/Ru ratio. An increase of specific activity is however observed in the hydrogenation of hydrocinnamaldehyde. It is suggested that tin, present mainly as Sn ions, enhances the reactivity of the C=O group. 相似文献
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本文介绍了北京首创轮胎公司新建工厂三复合冷喂料挤出生产线的调试情况,对三复合冷喂料挤出机基本结构、工艺特点做了概述,并且通过生产线出型胎面调试过程中遇到的问题,采取相应措施进行解决做了详细说明,通过近两年来的运行情况,总结出本生产线的使用优势。 相似文献
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C. Herranz Agustín J. Costa Lpez F. J. Domingo Campos 《European Journal of Lipid Science and Technology》1984,86(12):478-480
A group of not well known anionic phosphorus-containing surfactants have been obtained. In these surfactants the hydrophobic chain is directly linked to the phosphorus atom through a P-C bond. These products are alkylphosphinates with C10, C12, C14 and C16 alkylic chains. The products have been prepared by direct reaction between sodium hydrophosphite and the corresponding α-olefin, using tert-butyl perbenzoate as reaction initiator. Surfactants properties such as surface tension, foaming power and wetting power of the sodium and ammonium salts of all these alkylphosphinates have been measured. 相似文献
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Shraddha SinghV.K. Srivastava 《Ceramics International》2011,37(1):93-98
The electrical properties of carbon/carbon (C/C) and carbon/carbon-silicon carbide (C/C-SiC) ceramic composites were measured. The results show that the capacitance decreases rapidly with an increase in frequency and it becomes constant above a frequency of 500 kHz, whereas the dissipation factor increases with increasing frequency. C/C-SiC composites give higher value than C/C composites due to the presence of microcracks. 相似文献
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Robert A. Singer 《Israel journal of chemistry》2020,60(3-4):294-302
Numerous ligands have been designed for the Buchwald-Hartwig Amination (BHA). Among the ligands developed is BippyPhos. This ligand was originally designed to enable a coupling of primary amines with aryl halides. Further studies showed that the ligand has fairly broad utility for Pd-catalyzed C−N, C−O and C−C couplings. This review describes the various Pd-catalyzed applications involving BippyPhos as a supporting ligand. While BippyPhos may not often be the most optimal ligand for various Pd-catalyzed couplings, it typically will provide adequate results as a starting point prior to screening for optimization. 相似文献
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采用浸渍法制备 Pt/C,Pd/C和 Pd- Bi/C催化剂。将三种催化剂对葡萄糖的脱氢和加氧氧化两种反应的催化效果作对比研究 ,发现三种催化剂对这两个反应有着完全相反的催化顺序 :催化脱氢时 Pt/C效率最高 ,而加氧反应中 Pd- Bi/C却具有绝对优势。为解释此结果 ,结合催化剂的表征 [2 ] ,尝试提出了催化加氧和脱氢的机理 ,并确定了 Pd- Bi/C催化剂中的最佳 Bi/Pd比和两种催化反应的最佳工艺条件。实验结论 :Pt/C用于葡萄糖催化脱氢为可行的工业化途径 ,而 Pd- Bi/C对葡萄糖的催化加氧则具有挑战酶催化过程的能力 ,有一定的市场应用前景 相似文献
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Fiber-bundle push-out, single-fiber push-in, and single-fiber push-out tests were conducted in order to examine the applicability of these methods for determining the interfacial shear strength of carbon-carbon composites. The fiber-bundle push-out test resulted mostly in fractures along the fiber/matrix interface but created a small amount of fractures in the matrix. Hence, the evaluated strength was regarded as an approximate value. In order to precisely evaluate the interfacial strength, push-in and push-out tests for a single fiber were performed using a micro-Vickers indentation tester. In these tests, the load has to be placed within a target fiber, and the indentation should not extend to the matrix. This condition restricted the load that could be applied to a carbon fiber. Within this limit, a single carbon fiber could not be pushed-in. For the sake of load reduction, single-fiber push-out tests were conducted using thin specimens. The thickness appropriate for a single-fiber push-out specimen was estimated based on the interfacial shear strength obtained by the bundle push-out tests. Below this thickness, single-fiber push-out tests could be successfully performed. 相似文献