磷钨酸催化合成苯甲酸

以苯甲醛为原料,质量分数为30%的过氧化氢为氧化剂,在没有任何有机溶剂存在的情况下,采用磷钨酸(H3PW12O40)作催化剂来合成苯甲酸,实验结果表明,当n(苯甲醛)∶n(H3PW12O40)∶n(H2O2)=100∶0.7∶350,反应温度为75℃,反应时间为4h时,苯甲酸的收率可达83.46%;同时本文还讨论了H3PW12O40加入量、过氧化氢加入量、反应温度以及反应时间等因素对反应的影响。     

1∶12系列多金属氧酸盐催化苯甲醛氧化反应的研究

以苯甲醛为原料,过氧化氢作氧化剂,1∶12磷钨杂多酸哌啶盐为催化剂,一步反应制得苯甲酸。考察了反应温度、物料比、催化剂用量及反应时间对反应的影响。反应产物抽滤烘干后,通过测熔点来进行分析。采用正交实验法对苯甲酸的合成路线进行优化设计,得出了最优化工艺条件:温度75℃,V(苯甲醛)∶V(过氧化氢)=1∶3.0,m(催化剂)=0.4 g,反应时间5 h,苯甲酸产率达96.7%。     

对氯苯甲酸的合成工艺研究

以对氯苯甲醛为原料,过氧化氢作氧化剂,在水作溶剂的碱性条件下,一步反应合成对氯苯甲酸。考察了碱的浓度、反应温度和物料摩尔比对反应产率的影响。实验结果表明:氢氧化钾浓度为40%,反应温度40℃,反应物质的量比n(对氯苯甲醛):n(30%过氧化氢)=1:4,对氯苯甲酸收率达89%。通过测熔点和红外光谱表征了目标产物对氯苯甲酸的结构。     

过氧化氢氧化苯甲醛制苯甲酸的研究

以过氧化氢为氧化剂,十六烷基三甲基钨磷杂多酸铵为催化剂,催化氧化苯甲醛制苯甲酸.考察了反应温度、催化剂用量、30%过氧化氢用量和反应时间对苯甲酸产率的影响.结果表明：苯甲醛10.1 mL,30%过氧化氢11.5 mL,催化剂0.16 g,90℃下反应6 h,苯甲酸的产率可达到74.9%.     

对氯甲基苯甲酸的绿色合成方法研究

以对甲基苯甲酸为原料,以盐酸做氯源,以过氧化氢做氧化剂和引发剂,高效率地合成对氯甲基苯甲酸。考察了反应温度、原料配比、反应时间对产物收率的影响。结果表明:当反应温度为35-40℃,原料配比n(对甲基苯甲酸)∶n(20%盐酸)∶n(27%双氧水)=1∶1.2∶1.2～1.3时反应收率最高且用时最短。产物收率可达98%以上。     

二苯乙烯型紫外线吸收剂的合成及其性能研究

以4-氯甲基苯甲酸甲酯和亚磷酸三乙酯为起始原料,经Arbuzov反应后,再分别与4-甲酰基苯甲酸甲酯、苯甲醛、4-叔丁基苯甲醛、4-氯苯甲醛、2,4-二氯苯甲醛发生Wittig-Horner反应,成功合成出5种不同官能团的紫外线吸收剂,反应条件为:温度50 ℃,n(Wittig试剂)∶n(醛)=1∶1,在DMF/甲醇体系下反应30 min,产率分别是81.4%、76.7%、69.0%、57.0%、50.1%,目标产物均通过核磁共振氢谱和熔点确认,并用紫外光谱测试其性能.     

2,5-二(二乙氨基甲基)对苯二酚在过氧化氢氧化苯甲醇制备苯甲酸中的应用研究

以30%过氧化氢作为氧化剂,对苯二酚与甲醛、二乙胺的Mannich反应产物2,5-二(二乙氨基甲基)对苯二酚与钨酸钠为催化剂,研究了苯甲醇氧化制备苯甲酸的反应,2,5-二(二乙氨基甲基)对苯二酚的辅助催化性能优于对苯二酚。最佳反应条件为:40.5mmol苯甲醇,n(钨酸钠)∶n(2,5-二(二乙氨基甲基)对苯二酚)∶n(苯甲醇)∶n(30%过氧化氢)=0.405∶0.489∶40.5∶273,3mL0.1mol/L硫酸,于95℃反应8h,在无有机溶剂的条件下苯甲醇可以被氧化为苯甲酸,一次结晶率为76.9%,催化体系的重复使用性能不太理想。     

对甲基苯磺酸催化合成4-乙酰氧基苯甲酸的研究

以对羟基苯甲酸和乙酸酐为原料,采用对甲基苯磺酸作催化剂合成4-乙酰氧基苯甲酸,考察了反应温度、反应时间、催化剂用量对产品的影响。实验结果表明酰化反应的优化条件n(对羟基苯甲酸)∶n(乙酸酐)∶n(对甲苯磺酸)=1∶2∶0.025,反应时间30min,反应温度80~89℃,产率达91.63%。     

苯甲酸类化合物的绿色合成

在钨酸钠、磺基水杨酸和十六烷基三甲基溴化铵催化下,以苯甲醛类化合物为原料,用30%过氧化氢作为氧化剂,合成了苯甲酸类化合物。研究了反应时间、过氧化氢用量和催化剂对苯甲醛氧化合成苯甲酸反应产率的影响,给出了绿色合成苯甲酸类化合物方法,得到了六个苯甲酸类化合物。     

过氧化氢催化氧化苯甲醇制苯甲酸

以质量分数为 30 %的过氧化氢 (H2 O2 )为氧源 ,探讨了Na2 WO4·2H2 O催化氧化苯甲醇制苯甲酸反应中酸性添加物的影响 ,在大多数情况下 ,酸性越强 ,苯甲酸的收率越高。用NaHSO4·H2 O作酸性添加物 ,对反应条件的优化研究表明 ,氧化反应的最佳条件为n(苯甲醇 )∶n(Na2 WO4·2H2 O)∶n(NaHSO4·H2 O)∶n(H2 O2 ) =10 0∶1∶1∶30 0 ,回流 7h ,苯甲酸收率达 82 .7%。     

乙烯酮(双乙烯酮)下游产品废水的治理技术

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。     

几种乙炔加压设备性能的比较

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。     

三种煤样燃烧热的测定

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。     

Semi-empirical equation of state of metals. Equation of state of aluminum

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.     

水泥水化热测定方法综述

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。     

小议汽车涂装工艺设计对涂装成本的影响

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。     

Measurement of the gradient of viscosity with composition of mixtures of non-ideal gases

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%.     

Calorimetric and Computational Study of Enthalpy of Formation of Diperoxide of Cyclohexanone

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.     

塔设备改造选型的分析

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）。     

Effect of degree of deacetylation of chitin on the properties of chitin crystallites

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