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以混合二甲苯为原料, Mn(Ⅲ)为氧化剂, 硫酸溶液为电解质, 采用槽内式超声电合成甲基苯甲醛. 探讨了选择性电合成甲基苯甲醛的可能性, 通过径向基(RBF)神经网络和遗传算法(GA)对选择性电合成甲基苯甲醛3种异构体的比例、 电流效率与混合二甲苯的用量、 硫酸浓度和电流强度的关系建立预测模型, 并运用GA确定模型中RBF神经网络的目标均方误差(Goal)和径向基函数的分布(Spread). 然后根据预测模型, 使用GA对电合成条件进行优化, 分别获得了电合成产物中对位甲基苯甲醛占优、 邻位和对位甲基苯甲醛占优以及电流效率最高时的电合成条件. 当采用上述条件进行实验时, 模型给出的预测结果分别为: 对位甲基苯甲醛占优的质量分数可达90.01%, 邻位和对位甲基苯甲醛占优的质量分数为80.38%, 电流效率达到最高时的邻位、 间位和对位甲基苯甲醛的质量分数分别为16.80%, 8.43%和74.77%; 而与之相对应的实际实验结果分别为90.10%和79.91%, 以及17.20%, 8.49%和74.31%, 二者之间的最大相对误差小于±2.24%, 表明所建立模型的预测值与实测值基本吻合. 相似文献
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使用新颖的纳米结构电极成对电合成葡萄糖酸锌和丁二酸.采用溶胶-凝胶法制备Ti基纳米TiO2(Ti/nanoTiO2)电极,同时采用电沉积法制备Ti基纳米TiO2-Pt(Ti/nanoTiO2-Pt)修饰电极.通过循环伏安研究发现,Ti/nanoTiO2-Pt电极对葡萄糖氧化及Ti/nanoTiO2电极对马来酸还原均具有高催化活性.以Ti/nanoTiO2-Pt电极为阳极、Ti/nanoTiO2电极为阴极,通过正交实验得到成对电合成葡萄糖酸锌和丁二酸的优化条件为:阳极和阴极电流密度分别为1.2A·dm-2和3.0A·dm-2,阳极液为0.4mol·L-1葡萄糖+0.6mol·L-1NaBr,阴极液为0.6mol·L-1马来酸+0.2mol·L-1NaCl,温度50℃.成对电合成的总电流效率达到170%. 相似文献
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非匀相二步间接电解合成苯甲醛的研究 总被引:16,自引:0,他引:16
用循环伏安法,极化曲线法和电解制备研究了Mn^2+/Mn^3+媒质非匀相二不间接电氧化甲苯合成甲醛过程,提出克服电流效率下降的电解液和化学反应液“双循环法”可保持电流效率在88%以上。 相似文献
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固定床电解槽变电流成对电解合成乙醛酸 总被引:8,自引:1,他引:7
对电解氧化乙二醛合成乙醛酸过程 ,固定床电解槽和变电流电解效果明显优于平板型电解槽和恒电流电解效果 .当阳极液中乙二醛和盐酸初始质量分数 (WCHOCHO 和WHCI)分别等于7.0 %和 8.0 %、阴极液为始终饱和的草酸溶液和微量的添加剂时 ,采用平均电流密度 (i)为 15 35A/m2 的变电流方式电解 ,阳极电流效率 (CEa)为 85 .3%、乙醛酸选择性 (RSa)为 93.9% ;阴极电流效率 (CEc)为 86 .7% ,乙醛酸选择性 (RSc)为 94 .0 % .阳极初产品中WCHOCOOH∶WCHOCHO≥ 4 0∶3,克服了阳极产品中乙二醛难以除去的困难 相似文献
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取代苯甲醛肟羧酸酯的合成及生物活性研究(Ⅱ)——α-烷硫基苯甲醛肟羧酸酯的合成及生物活性 总被引:3,自引:0,他引:3
肟醚及肟酯衍生物是一类具有优良的杀虫、杀菌、杀螨及除草活性的化合物,有关此类化合物的研究非常活跃[1,2].本研究组对拟除虫菊酯与芳香肟衍生物进行研究,发现菊酸肟酯类化合物具有良好的抗烟草花叶病毒和杀虫活性[3].本文在前期研究工作的基础上,将烷硫基... 相似文献
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在包含原料马来酸的硫酸溶液中, 通过原位阳极氧化法制备了Ti/TiO2膜电极, 然后采用极性转换技术在原溶液中电化学合成丁二酸. 采用XPS, XRD和SEM分析了膜电极上的元素组成、价态分布和氧化膜的晶相结构及表面形貌. 结果表明, 阳极氧化膜层内只含有Ti和O两种元素, 且Ti均为Ti4+; TiO2氧化膜是金红石相, 表观呈现带孔的条纹形貌. 通过循环伏安、恒电位阶跃和恒电流电解技术研究了Ti/TiO2原位氧化膜电极的电化学性质, 结果表明, 该膜电极对马来酸电还原合成丁二酸具有较好的电催化活性. 以钛基氧化钌电极(DSA)为阳极, Ti/TiO2原位氧化膜电极为阴极进行恒电流电解了实验. 结果表明, 丁二酸的还原产率为95.94%, 电流效率为95.57%, 产物纯度为99.28%, 熔点为185~187 ℃. 相似文献
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A. J. Aishah M.A. Hartini S. Normala A.M. Norhuda H. H. N Hanis H.M. Razif T. Sugeng 《天然气化学杂志》2007,16(3):273-277
Carbon dioxide fixation technique was developed as an alternative dechlorination method of chlorobenzenes.Electrolysis of chlorobenzene was carried out in a one-compartment cell fitted with an alu- minium anode and a platinum cathode.Electrolysis in N,N-dimethylformamide(DMF)solution contain- ing 0.1 M of tetrapropylammonium bromide(TPAB)at 0℃,100 ml/min of CO_2 flow rate and 120 mA/cm~2 of current density was found to be the optimum conditions of this electrocarboxylation,which gave 72% yield of benzoic acid from chlorobenzene.These conditions were then applied to 1,2-dichlorobenzene and 1,3-dichlorobenzene in order to convert them to their corresponding benzoic acids. 相似文献
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Jia Bin Yeo Jun Ho Jang Young In Jo Jeong Woo Koo Ki Tae Nam 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(2):e202316020
Utilizing CO2-derived formaldehyde derivatives for fuel additive or polymer synthesis is a promising approach to reduce net carbon dioxide emissions. Existing methodologies involve converting CO2 to methanol by thermal hydrogenation, followed by electrochemical or thermochemical oxidation to produce formaldehyde. Adding to the conventional methanol oxidation pathway, we propose a new electrochemical approach to simultaneously generate formaldehyde derivatives at both electrodes by partial methanol oxidation and the direct reduction of CO2. To achieve this, a method to directly reduce CO2 to formaldehyde at the cathode is required. Still, it has been scarcely reported previously due to the acidity of the formic acid intermediate and the facile over-reduction of formaldehyde to methanol. By enabling the activation and subsequent stabilization of formic acid and formaldehyde respectively in methanol solvent, we were able to implement a strategy where formaldehyde derivatives were generated at the cathode alongside the anode. Further mechanism studies revealed that protons supplied from the anodic reaction contribute to the activation of formic acid and the stabilization of the formaldehyde product. Additionally, it was found that the cathodic formaldehyde derivative Faradaic efficiency can be further increased through prolonged electrolysis time up to 50 % along with a maximum anodic formaldehyde derivative Faradaic efficiency of 90 %. 相似文献
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A preparative method for synthesis of adipic acid in 47% yield was developed. The method is based on cyclohexanol oxidation in an undivided cell on the NiOOH electrode in aqueous alkali. A possibility of the step-by-step process was studied: oxidation of cyclohexanol to cyclohexanone (75% yield) and subsequent oxidation of cyclohexanone to adipic acid (52% yield). The electrosynthesis of adipic acid is accompanied by the formation of minor amounts (up to 10%) of glutaric and succinic acids. 相似文献