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固体酸催化合成邻苯二甲酸二戊酯的研究 总被引:2,自引:0,他引:2
以苯酐和正戊醇为原料,采用自制的固体酸SO4^2-/SiO2、SO4^2-/Fe2O3、SO4^2-/SnO2及SO4^2-/TiO2作为催化剂合成邻苯二甲酸二戊酯(DAP),分别考察固体酸催化剂的种类、固体酸催化剂的用量、醇酐比、反应时间等因素对合成DAP产率的影响。实验结果表明,其优化的工艺操作条件为:苯酐0.1mol,固体酸催化剂SO4^2-/SiO2 1.7g,醇酐比2.4:1,带水剂二甲苯20mL,反应时间3.5h,其产品收率达91.3%以上。SO4^2-/SnO2作为该反应的催化剂具有催化活性高、寿命长、可多次重复使用、产物易纯化分离且产品色泽浅等优点,可望代替传统的浓硫酸作催化剂应用于DAP的合成。 相似文献
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用共沉淀法制备了固体超强酸S2O8^2-/ZrO2-CeO2催化剂,通过XRD,FTIR,BET,TEM,DSC/TG等分析手段对其结构进行了表征,并考察了其对乳酸丁酯合成反应的催化活性。结果表明.Ce的引入可以有效地抑制ZrO2晶粒由四方相向单斜晶相转变和催化剂表面含硫物种的流失;当焙烧温度高于500℃时,体系内部有四方相Ce0.16Zr0.84O2固溶体形成,最佳焙烧温度为600℃。在n(乳酸):n(正丁醇)=1.0:3.0,。(S2O8^2-/ZrO2-CeO2)=12.0%,反应温度145℃,反应时间2.0h的条件下,S2O8^2-/ZrO2-CeO2催化剂对乳酸的酯化率达96.6%。 相似文献
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以柠檬酸和正辛醇为原料,采用自制的纳米固体酸S04^2-/SnO2、SO4^2-/ZrO2、SO4^2-/TiO2及SO4^2-/Fe2O3催化剂合成无毒增塑剂柠檬酸三辛酯(trioctylcitrate,TOC)。分别考察了纳米催化剂种类、催化剂用量、醇/酸物质的量比、反应时间、反应温度等因素对合成TOC反应酯化率的影响,对合成的产品进行红外光谱分析。实验结果表明,自制的固体酸SO4^2-/SnO2催化合成无毒增塑剂柠檬酸三辛酯的最佳反应条件:催化剂用量为1.0g,酸醇比为1:6.3,反应时间1.0h,反应温度190℃。在最佳反应条件下,柠檬酸三辛酯的酯化率可达到98.5%。 相似文献
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在室温条件下合成了N-3-羧基水杨醛-1,2-丙二胺Schiff碱单核镍配合物Ni(HCSP)2·H2O[H2CSP=N-3-羧基水杨醛-1,2-丙二胺Sehiff碱].通过IR对配体及配合物的晶体结构进行了表征,并用单晶X射线衍射测定了结构.配合物属单斜品系,空间群P2(1)/c,晶体学参数:a=0.9756(2)nm,b=1.4236(3)nm,c=1.7403(4)nm,α=90°,β=98.951(3)°,γ=90°,分子式C22H28NiN4O7,Mr=519.19,V=2.3878(8)nm^3,Z=4,Dc=1.430Mg/m^3,F(000)=1068,R.=0.0719,wR2=0.1844,S=0.962.化合物分子由两个一价阴离子HCSP^-和一个二价镍离子组成. 相似文献
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掺铬铝酸钇红色颜料的合成、结构和性能表征 总被引:6,自引:0,他引:6
研究了高温固相合成制备掺铬铝酸钇红色颜料的方法,着重考察了灼烧温度(1000-1400℃)、灼烧时间(1-2h)、主要原料配比(Al/Y:1:0.5—1:1.5,Cr2O3%:0.3%-5%)等实验条件对产物结构和色泽的影响。XRD等方法对样品进行的相态分析表明,主相为铝酸钇石榴石相;运用反射光谱对红色颜料的色泽进行了反射峰位和相关强度的表征。当Y2O3:Al2O3摩尔比为1:1,掺杂3%的Cr2O3作显色剂,在少量矿化剂存在时,在1300℃下灼烧1 h,得到了色坐标为x=0.577,Y=0.401的红色陶瓷颜料。 相似文献
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以硫酸钻、邻菲咯啉(phen)和3-羟基-1-金刚烷甲酸(HOC10H14COOH)为原料,合成了配合物[Co(HOG10H14COO)2(H2O)(phen)]·H2O;利用元素分析、红外光谱、热重分析对产物进行了表征,采用单晶X射线衍射方法测定了其晶体结构.结果表明,所合成的配合物C34H42N2O8Co属于单斜晶系,空间群C2/c,a=2.69798(7)nm,b=1.14319(3)nm,c=2.29092(6)nm,β=120.498(1)°,V665.63,F(000)=2808,Dc=1.452g·cm^-3,μ(Mo-Kα)=0.765mm^-1;R1=0.0805,wR2=0.2209,其通过氢键和π-π堆积作用相结合,形成稳定的二维超分子结构. 相似文献
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V. I. Bol'shakova L. I. Demenkova É. N. Shmidt V. A. Pentegova 《Chemistry of Natural Compounds》1989,24(6):691-694
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988. 相似文献
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利用手持技术改进测定乙醇分子结构实验 总被引:1,自引:0,他引:1
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。 相似文献
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由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。 相似文献
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Effect of the Method of Modification of Zeolite X on Selectivity of Catalytic Methylation of Toluene
Voloshyna Yu. G. Pertko O. P. Patrylak L. K. 《Theoretical and Experimental Chemistry》2019,54(6):395-400
Theoretical and Experimental Chemistry - The effect of the method of modification of catalysts based on zeolite X by cesium and magnesium cations (ion exchange and impregnation) on the selectivity... 相似文献
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Influence of viscosity of medium on processes of oxygen quenching of excited states of mesoporphyrin
E. I. Kapinus V. A. Ganzha B. M. Dzhagarov E. I. Sagun V. B. Pavlenko 《Theoretical and Experimental Chemistry》1989,25(2):146-151
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989. 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
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Kopranenkov V. N. Makarova E. A. Dashkevich S. N. Luk'yanets E. A. 《Chemistry of Heterocyclic Compounds》1982,18(11):1218-1218
Chemistry of Heterocyclic Compounds - 相似文献