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1.
锌修饰亚铬酸铜催化甘油制备羟基丙酮   总被引:1,自引:0,他引:1  
李浔  谢丹  袁燕平  曹建平 《应用化工》2011,40(6):931-934
以锌修饰的亚铬酸铜为催化剂,考察了锌含量、催化剂煅烧温度、催化剂用量、反应温度等条件对甘油脱水制备羟基丙酮的影响。结果表明:助剂锌修饰作用提高了亚铬酸铜的催化剂活性,延长了催化剂的使用次数,提高了羟基丙酮选择性和产率。适宜催化剂制备及反应条件为:硝酸锌浸渍液浓度为10%,焙烧温度为350℃,催化剂用量为4%,反应温度为220℃,羟基丙酮选择性达88.9%。  相似文献   

2.
以磺化苯乙烯阳离子交换树脂为催化剂,催化环己烯和乙酸反应合成乙酸环己酯,考察了反应温度、反应时间、催化剂用量和原料配比对反应的影响。结果表明,较适宜的反应条件为:环己烯用量为0.1 mol,酸烯摩尔比为4:1,催化剂用量为0.96 g,反应温度为90℃,反应时间为5 h。在此条件下酯收率为83.2%,催化剂使用5次仍保持较高活性。  相似文献   

3.
环己醇催化脱水制备环己烯   总被引:4,自引:1,他引:4  
在催化剂ZrO2 SO42-存在下,研究了环己醇脱水制备环己烯的反应,考察了催化剂的用量、反应温度和反应时间对脱水反应的影响。最佳工艺条件为:催化剂用量为环己醇质量的10%,温度为170~180℃,反应时间1h,收率达87.4%。  相似文献   

4.
水合肼中间体丁酮连氮的合成工艺研究   总被引:2,自引:0,他引:2  
以丁酮、氨气和过氧化氢为原料,研究了在催化剂条件下水合肼中间体丁酮连氮合成的不同工艺条件;考察了催化剂种类及其用量、反应时间、反应温度、双氧水用量各因素对反应收率的影响,结果显示,当催化剂选用甲酰胺,催化剂用量0.5mol,反应时间6h,双氧水用量为0.5mol时,反应温度60℃,丁酮连氮收率达到83.49%。  相似文献   

5.
以环己醇为原料、钨酸钠和磷钨酸配合为催化剂,探讨了双氧水为氧化剂氧化环己醇合成环己酮的工艺方法。并考察了反应温度、催化剂配比、双氧水用量以及反应时间等因素对反应的影响,确定了最佳反应条件:催化剂钨酸钠和磷钨酸的配比为10∶1,双氧水的用量为2.5~3mL,反应温度为80℃,时间为6h。  相似文献   

6.
以活性炭负载对甲苯磺酸作催化剂,山梨醇聚氧乙烯醚和油酸为原料,合成山梨醇聚氧乙烯醚油酸酯。考察了催化剂用量、反应温度、反应时间等条件对反应的影响。较优的合成条件为:真空脱水,催化剂用量为总物质量的0.25%,反应温度为130~135℃,反应时间为3.0 h,满足指标要求。  相似文献   

7.
以羰基镍为源,制备了一系列高活性、低含量负载型镍催化剂。利用苯乙烯的加氢反应考察了催化剂载体类型、反应温度、反应压力、催化剂用量等因素对催化剂性能的影响以及催化剂的重复性能。结果如下:LY8062c载体的性能最为优异;反应活性随反应温度和压力的增大而增强;催化剂的用量少,镍的负载量低;本方法制备的催化剂重复使用性能较好。  相似文献   

8.
聚合硫酸铁的制备   总被引:2,自引:0,他引:2  
本文介绍了以硫酸亚铁为原料,氧气为氧化剂,亚硝酸钠为催化剂.在实验条件下进行催化氧化制备聚合硫酸铁.探讨了反应温度、硫酸用量、助催化剂和催化剂用量对反应速率及产品质量影响。  相似文献   

9.
以SnCl4·5H2O/C为催化剂、用乙酸和乙醇为原料,直接酯化合成乙酸乙酯.讨论了醇酸物质的量比、反应温度以及催化剂用量等因素对酯化反应的影响,得出最佳反应条件为催化剂用量为2.5g,乙醇和乙酸的物质的量比为11.5,反应温度为95℃.催化剂重复使用率好,酯的产率高达93.38%.  相似文献   

10.
考察了摩尔比不同、煅烧温度不同的ZnO-TiO2复合催化剂对尿素醇解合成碳酸二甲酯的催化活性。讨论了催化剂用量、反应时间、反应温度和原料配比等因素对合成碳酸二甲酯(DMC)收率的影响。实验结果表明ZnO-TiO2复合催化剂上最佳反应条件为:催化剂用量为反应体系总质量的1%,反应时间为4 h,反应温度为160℃,甲醇和尿素的摩尔比为14。碳酸二甲酯(DMC)的最高收率为19.2%。  相似文献   

11.
陈建文 《广东化工》2006,33(6):79-81
乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。  相似文献   

12.
阐述并比较了几种加压设备在乙炔加压清净过程中的性能和特点。  相似文献   

13.
本文通过三个厂家提供的三种煤样燃烧热的测定,由测定结果综合得出3号煤样燃烧最完全、燃烧热也最大,是三个煤样中最好的一种。  相似文献   

14.
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3. __________ Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008.  相似文献   

15.
水泥水化热是中、低热水泥和核电工程用水泥的一项关键的技术指标。全球范围内测定水泥水化热的方法有溶解法、直接法/半绝热法、等温传导量热法三种。本文总结了中、美、欧相关方法标准,对其测试原理、仪器设备、试验过程等方面进行了比对,并对其在领域的应用做了简单的概括。  相似文献   

16.
论述了涂装工艺设计对涂装设备投资、涂装生产成本的影响。  相似文献   

17.
A perturbation viscometer is a differential capillary viscometer that measures the logarithmic viscosity gradient of the viscosity-composition curve for gas mixtures. Measurements are made at different gas mixture compositions. Integration of the logarithmic viscosity gradients measured over the full composition range gives the mixture viscosity relative to the viscosity of one of the pure components of the gas mixture. This method is attractive because, for measurements of equal precision, integration of the gradients is potentially an order of magnitude more precise than measurement of the viscosities directly. It can also work at high and low temperatures and perhaps high pressures.The perturbation viscometer has been used to make measurements on ideal gas mixtures at ambient and elevated temperatures. The situation is more complicated when the gas mixtures are non-ideal. Extra effects due to density differences, molar volume change on mixing and differential thermal expansion may be measured in addition to the desired viscosity change producing systematic errors in the results. Thus, a more sophisticated apparatus is required. The standard perturbation viscometer has been modified to separate out the extra effects to permit measurement of the true change in viscosity. In addition, the theoretical operation of the modified apparatus has been revised to account for the design changes to permit calculation of the viscosity-composition profiles from the results.The apparatus has been tested using helium-HFC-125 mixtures and two new viscosity-composition profiles are presented for these mixtures at 23 and . Internal consistency tests have been used to confirm that the data produced are of high quality with an estimated uncertainty in the viscosity ratio data at of 0.9% and at of 1.5%.  相似文献   

18.
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out.  相似文献   

19.
塔设备改造选型的分析   总被引:2,自引:0,他引:2  
黄洁  张学 《化工设计》1997,7(3):23-27
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。  相似文献   

20.
In the present article, chitin from crab shell was systematically deacetylated using a NaOH treatment with control of the reaction time. The degree of deacetylation, monitored using solid-state NMR, revealed that the reaction was pseudo-first order. Based on this, swollen and NaOH-saturated particles are proposed as the reaction system. The weight loss of the partially saponified and neutralized samples after HCl hydrolysis increased linearly with the degree of deacetylation. The crystallinity of the samples was found to increase after acid hydrolysis. According to conductimetric titration, the surface charge density of the crystallites, after acid hydrolysis, was found to increase with base treatment time. The effect of surface charge on the formation of a chiral nematic phase, due to the rodlike nature of the crystallites, was explored. These results show that because the contribution of charged particles to the ionic strength was significant the double layer compression was affected, especially since the surface charge density was close to the Manning limit. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65:373–380, 1997  相似文献   

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