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合成了煤焦油碳基固体酸,并对其结构进行了表征.通过叔丁醇与问甲基苯酚合成了2-叔丁基-5-甲基苯酚,探讨了煤焦油碳基固体酸对烷基化反应的催化活性.实验结果表明,煤焦油碳基固体酸是烷基化反应的良好催化剂,在间甲基苯酚0.01 mol、催化剂用量为0.1 g、反应温度为110℃、反应时间为3 h、醇酚摩尔比为2.5:1的优... 相似文献
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A ternary solid complex Yb(Et2dtc)3(phen) was obtained from the reaction of hydrous ytterbium chloride with sodium diethyldithiocarbamate (NaEt2dtc), and 1, 10-phenanthroline (o-phen·H2O) in absolute ethanol.The bonding characteristics of the complex were characterized by IR.The result shows Yb3 bands with two sulfur atoms in the Na(Et2dtc)3 and two nitrogen atoms in the o-phen.The enthalpy change of liquid-phase reaction of formation of the complex ΔrHθm (l), was determined as being (-24.838±0.114) kJ·mol-1 at 298.15 K, by an RD-496 Ⅲ type heat conduction microcalormeter.The enthalpy change of the solid-phase reaction of formation of the complex ΔrHθm (s), was calculated as being (108.015±0.479) kJ·mol-1 on the basis of an appropriate thermochemistry cycle.The thermodynamics of liquid-phase reaction of formation of the complex was investigated by changing the temperature during the liquid-phase reaction.Fundamental parameters, the activation enthalpy, ΔHθ≠, the activation entropy, ΔSθ≠, the activation free energy, ΔGθ≠, the apparent reaction rate constant k, the apparent activation energy E, the pre-exponential constant A, and the reaction order n, were obtained by a combination of the reaction thermodynamic and kinetic equations with the data from the thermokinetic experiments.At the same time, the molar heat capacity of the complex cm, p, was determined to be (86.34±1.74) J·mol-1·K-1 by the same microcalormeter.The constant-volume combustion energy of the complex, ΔcU, was determined to be (-17954.08±8.11) kJ·mol-1 by an RBC-Ⅱ type rotating-bomb calorimeter at 298.15 K.Its standard enthalpy of combustion, ΔcHθm, and standard enthalpy of formation, ΔfHθm, were calculated to be (-17973.29±8.11) kJ·mol-1 and (-770.36±9.02) kJ·mol-1, respectively. 相似文献
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以Pd/C为催化剂直接催化氢化2-氨基-4,6-二羟基-5-亚硝基嘧啶削备2,5-二氨基-4,6-羟基嘧啶,采用正交设计方法考察了碱的浓度、溶剂、催化剂用量、温度、反应时间等对反应的影响,收率在86%以上。 相似文献
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甲基橙褪色分光光度法测定亚硝酸根的动力学及机理探究 总被引:1,自引:0,他引:1
研究了在酸性介质中,NO_2~-对溴酸钾氧化甲基橙褪色反应的催化作用,以及在一定的条件下反应的动力学性质,测定了反应的表现活化能为69.20KJ·mol~(-1),25℃时反应的速率常数为10.261×10~7,反应为3.5级反应。利用动力学参数探讨了反应机理,并测试了干扰离子对反应的影响。 相似文献
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研究了试剂4,6-二氯-2-(2-咪唑四氢)-氨基嘧啶(DTIAP)与铜的显色反应,建立了光度法测定微量铜的新方法。试验结果表明:在乳化剂十六烷基三甲基溴化铵(CTMAB)存在下,在Na2HPO4-KH2PO4缓冲溶液中,Cu2+与DTIAP发生灵敏的显色反应,形成了一种稳定的摩尔比1:2的黄色配合物,其最大吸收波长为383nm,Cu2+量在0-0.9mg/L范围内符合比尔定律,表观摩尔吸光系数ε=2.03×104L.mol-1.cm-1,相关系数r=0.9991。将该方法用于茶叶,香米中微量铜的测定,均获得满意的结果。 相似文献
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研究了不同原料的选取,升温速度的控制以及太西煤的催化氧化改性等因素对于炭化物结构的影响。活化后得到的活性炭的碘值、四氯化碳值均增大,吸附性增强。 相似文献