双金属Mo-Ti-SBA-15的制备及催化环己烯环氧化性能

采用一步法分别制备了单金属介孔催化剂Ti-SBA-15-(36)、Mo-SBA-15-(180/28)和双金属介孔催化剂Mo-Ti-SBA-15-(X)。考察了双金属催化剂Mo-Ti-SBA-15-(X)中Mo含量对催化剂结构和催化性能的影响;分析了催化剂活性差异的原因并探讨了双金属催化剂的协同催化机理。对影响催化环氧化反应的主要因素进行了考察。结果表明:双金属催化剂Mo-Ti-SBA-15-(180/28)在环氧化反应中的催化效果优于单金属催化剂。当反应时间为8 h、反应温度为80℃、催化剂剂量为25 mg、以2.5 mmol环己烯为底物、叔丁基过氧化氢(TBHP)为氧源、1,2-二氯乙烷为溶剂时,Ti-SBA-15-(36)、Mo-SBA-15-(180/28)和Mo-Ti-SBA-15-(180/28)为催化剂对应的环己烯转化率分别为41.07%、46.44%和98.33%,选择性分别为97.56%、93.19%和98.86%。Mo-Ti-SBA-15-(180/28)催化剂经过5次循环利用,环己烯的转化率和选择性均超过95%和97%,说明该催化剂具有很好的可循环利用性。     

“一锅法”合成双金属催化剂Co-Ti-SBA-15及其环氧化性能研究

以硝酸钴和钛酸四丁酯为金属前驱体,采用"一锅法"制备了Co-SBA-15-(180)、Ti-SBA-15-(36)和Co-Ti-SBA-15-(30)-(5)催化剂,并用于催化烯烃环氧化反应中。采用N_2吸附脱附、X-射线衍射、透射电子显微镜、扫描电子显微镜和X-射线能谱技术对催化剂进行表征。结果表明,在反应温度为80℃、1,2-二氯乙烷用量为10 mL、催化剂质量为100 mg、环己烯物质的量为10 mmol、叔丁基过氧化氢物质的量为10 mmol、反应时间为8 h的条件下,Co-Ti-SBA-15-(30)-(5)双金属催化剂对环己烯进行环氧化的转化率和选择性分别达到了92. 70%和94. 67%,明显高于Co-SBA-15-(180)和Ti-SBA-15-(36)单金属催化剂。     

Ti-SBA-15介孔分子筛催化制备环氧橡胶籽油的研究

以橡胶籽油(RSO)为原料,采用非均相介孔分子筛催化剂Ti-SBA-15催化制备环氧橡胶籽油(ERSO),探讨了催化剂用量、氧化剂叔丁基过氧化氢(TBHP)用量、反应时间、反应温度等因素对环氧化反应的影响。结果表明,Ti-SBA-15介孔分子筛催化剂催化制备ERSO的最佳工艺条件为:催化剂Ti-SBA-15用量0.062%(摩尔分数,以RSO物质的量计),TBHP与RSO物质的量比为1.3:1,反应时间6 h,反应温度70℃,此条件下制备的ERSO环氧值为68.9 mmol/g,产物转化率为82.22%,双键转化率为69.93%。通过FT-IR对比分析,进一步证实了环氧基团的生成。     

硫酸化Ti-SBA-15的制备及其催化氧化脱硫

以正硅酸乙酯为硅源、钛酸正丁酯为钛源、聚(乙二醇)-block-聚(丙二醇)-block-聚(乙二醇)为模板剂,采用水热法分别合成了介孔分子筛SBA-15和Ti-SBA-15,采用硫酸对其酸化后制得H2SO4/SBA-15和H_2SO_4/Ti-SBA-15。通过傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、BET氮气吸附-脱附等温方法、电子扫描电镜(SEM)及透射电镜(TEM)对SBA-15、H_2SO_4/SBA-15和H_2SO_4/Ti-SBA-15结构、孔道分布和表面形貌进行了表征。以制备的分子筛为催化剂,过氧化环己酮(CYHPO)为氧化剂和乙腈为萃取剂评价其催化氧化脱除模拟油中二苯并噻吩(DBT)性能。当反应温度为343K,反应时间为60min,乙腈为7.5mL,CYHPO与DBT的摩尔比为5∶1,催化剂用量为0.05g时,SBA-15、H_2SO_4/SBA-15和H_2SO_4/Ti-SBA-15的脱硫率分别为36.1%、57.8%和65.4%。这表明酸化和金属Ti同时改性的SBA-15具有较好的催化氧化脱硫活性。     

SBA-15分子筛负载氮化碳催化二氧化碳与环氧化合物环加成反应

二氧化碳的催化活化是其作为C1资源利用的关键。为了开发高效二氧化碳活化催化剂,将二聚氰胺通过浸渍法负载到介孔分子筛SBA-15孔道中,高温焙烧后,得到SBA-15负载的石墨相氮化碳g-C3N4催化剂。采用透射电镜、X射线衍射、N2吸附和X射线光电子能谱对催化剂进行表征。结果表明,负载g-C3N4后,SBA-15分子筛的介孔结构未发生明显变化,g-C3N4以纳米态分布于SBA-15分子筛的孔道中。将g-C3N4/SBA-15催化剂用于催化二氧化碳与环氧化合物环加成反应制备环状碳酸酯,考察催化剂组成和反应条件对催化性能的影响。结果表明,g-C3N4/SBA-15催化剂有效催化二氧化碳与环氧化合物环加成反应。以g-C3N4/SBA-15为催化剂,在反应温度140℃、反应压力3.5 MPa、反应时间4 h、Zn Br2物质的量分数为1.0%和二聚氰胺负载质量分数为20%条件下,环状碳酸酯产率达91.6%,g-C3N4/SBA-15催化剂制备工艺简单,原料价廉,催化性能优异。     

负载型固体酸催化合成生物柴油

以固体酸TSOH/HY-SBA-15（对甲苯磺酸改性的介孔分子筛）为催化剂,催化大豆油和甲醇制备生物柴油,考察了反应的最适宜条件。结果表明,催化剂为(0.5 mol/L)TSOH/(10 %)HY-SBA-15,反应温度为180 ℃,反应时间为7 h,n(醇)/n(油)为25,催化剂用量为油质量的5 %,溶剂用量为油质量的30 %,生物柴油的收率可达到94.6 %。     

金属卟啉仿生催化环戊烷选择氧化的研究

研究了金属卟啉仿生催化环戊烷选择氧化的反应。结果表明,反应时间、温度、压力、催化剂浓度和类型对反应具有明显的影响。其中,反应温度和压力对反应总选择性影响最大,反应适宜的条件是温度145℃,压力2.5 MPa,时间4 h,金属卟啉用量14×10~(-4)mol%,搅拌速率800 r/min。不同中心金属离子的金属卟啉催化环戊烷氧化的活性顺序为FeCoMn。其中,催化效果较好的催化剂为T(o-NO_2)PPFeCl,主产物戊二酸、环戊醇和环戊酮的总收率和总选择性分别为6.2%和86.1%。     

RhNi/SBA-15纳米催化剂的制备及其催化水合肼分解制氢性能

通过浸渍还原法将RhNi纳米颗粒负载在SBA-15(介孔二氧化硅)上制备出不同金属比的RhNi/SBA-15催化剂，进一步考察催化剂的结构及其催化水合肼制氢的性能。结果表明：RhNi/SBA-15催化剂中形成RhNi双金属，Rh和Ni双金属之间的协同作用有效提升催化剂活性。所制RhNi/SBA-15催化剂中Rh和Ni物质的量之比为9:1，在反应温度为323 K,NaOH浓度为0.15 mol/L时，该催化剂具有较高的活性，转化频率(TOF)为2 569.6 h^-1，经过5次循环后仍保持良好的催化活性。     

锡卟啉的合成及其绿色催化氧化环己烯

考察催化剂金属锡次卟啉二甲酯催化氧化环己烯的反应性能。探讨了在催化氧化过程中,反应温度、压力、时间、催化剂用量等因素对环己烯转化率和产物选择性的影响,并结合GC-MS在线分析检测。结果表明,当温度100℃、压力0.8 MPa、时间7 h、催化剂用量0.5 mg(7.6×10-4mmol)、环己烯10 mL(98 mmol)的条件下,环己烯的转化率达84%,相应产物2-环己烯-1-醇和2-环己烯-1-酮的总选择性为94%,并对该反应的催化氧化反应机理进行了初步研究。     

钛硅分子筛负载的Na-W-Mn催化剂上甲烷氧化偶联反应

以Na-W-Mn为活性组分,探究了Ti-SBA-15,TS-1,Ti-MWW和SiO24种载体负载的催化剂在不同反应温度下的甲烷氧化偶联反应性能,采用X射线衍射(XRD)、N2物理吸附、H2程序升温还原(H2-TPR)和X射线光电子能谱(XPS)等表征方法对催化剂进行了分析。结果表明,Na2WO4和Mn2O3活性相对反应至关重要。Ti的掺杂能有效提高W在较低温度下活化甲烷的速率,并促进催化剂的活性组分向表面迁移。Ti-SBA-15分子筛也提高了催化剂表面活性组分和活性氧物种的浓度。多种作用协同使Ti-SBA-15分子筛负载的催化剂在较低温度下的催化活性远高于其他3种催化剂,在720℃下CH4转化率为22%,C2选择性为63%。     

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