Electrooxidation of Benzene to Benzoquinone in a Packed Bed Reactor

苯在固定床电化学反应氧制备对苯二醌．阳极和阴极分别为多孔铅合金和铅粒．电解液是１ｍｏｌ／ｌ硫酸水溶液，苯分散于电解液中．最佳电解条件：电解液流速ｕ＝０．１９ｍ．ｓ１，反应器厚度Ｌ＝１０ｍｍ，电极电位Ｅ＝１．６Ｖ，电流Ｉ＝１０Ａ和苯含量ＣＢ＝２４％，电流效率ＣＥ是６２．９％．A packed electrode reactor was used to oxidize to benzoquinone. Anode bed of the reactor has a size of 10～30 mm×450 mm×50 mm(thickness×length×width),and was packed porous lead alloy. A dispersion of benzene in 1 mol/L aqueous sulfuric acid was passed through the reactor. Current efficiency for benzoquinone generation is 62.9% at optimal operating condition: velocity of electrolyte flow, 0.19 ms -1 ;current, 10 A; thickness of anode bed, 10 mm, and percentage of benzene, 24%.作者联系地址：华东理工大学联合化学反应工程研究所反应工程国家重点实验室Author's Address: UNILAB Research Center of Chemical Reaction Enginering, East China University of Science and Technology,State Key Laboratory of Reaction Enginering,Shanghai,20023

Kinetic Study of Electrooxidation of Benzene

Ｃｌａｒｋ等［１］研究苯阳极氧化过程，认为二氧化铅是最合适的电极，苯是二级反应，苯在阳极上首先氧化为产物对苯二醌，产物可进一步氧化成马来酸，直至氧化成二氧化碳．但Ｉｔｏ［２］等研究表明苯阳极氧化还有一个并行反应：苯直接氧化为马来酸．Ｆｌｅｓｚａｒ和Ｐ...A reaction kinetic study for electrochemical oxidation of benzene was performed on a PbO 2 rotating disk electrode in 1 mol/L H 2SO 4 aqueous solution. The reaction orders, the activation energies and transfer coefficient were measured, and the kinetic expression was obtained.作者联系地址：华东理工大学联合化学反应工程研究所反应工程国家重点实验室Author's Address: UNILAB Research. Center of Chem. Reaction Eng., East China Univ. of Sci. and Tech., Shanghai 20023

ELectro-oxidation of Glyoxal to Glyoxalic Acid

本文介绍了一种用电化学法合成乙醛酸的新方法 ,采用以DSA作阳极材料的离子交换膜电解槽和周期性间歇操作方式 ,研究了乙二醛和盐酸混合体系中各种工艺条件对电流效率(CEa)和乙醛酸收率 (RSa)的影响 ,得最佳电解条件 :反应温度 30～ 40℃ ,电解液流速 1.4m/s,电极电流密度 45 0A/m2 ,乙二醛初始浓度 (wt%以下同 ) 9.1%～ 16 .0 % ,盐酸初始浓度 4%～ 6 % ,在此条件下电解乙二醛 ,乙醛酸收率 91.1% ,电流效率 80 .0 % .An investigation has been made to obtain the glyoxalic acid by the electrochemical oxidation of glyoxal solution with hydrochloric acid under various experimental conditions.The cell used consists of a lead cathode, a DSA anode and a cation_exchange membrane of model CM001.The current efficiency and yield for glyoxalic acid generation were 80.0% and 91.1% respectively, under optimal operating conditions: velocity of electrolyte flow 1.4 m·s -1 ,current density 450A·m -2 ,temperature 30～40 ℃,initial concentration of glyoxal and hydrochloric acid 9.1%～16.0%, 4%～6%, respectively.作者联系地址：华东理工大学联合化学反应工程研究所!反应工程国家重点实验室上海200237,华东理工大学联合化学反应工程研究所!反应工程国家重点实验室上海200237,华东理工大学联合化学反应工程研究所!反应工程国家重点实验室上海200237,华东理工大学联合化学反应工程研究所!反应工程国家重点Author's Address: UNILAB Research Center of Chemical Reaction Eenginering, East China University of Science and Technology, State Key lab.for Reaction Engineering,Shanghai,200237,China$$

Varying Current Electro-synthesis of Glyoxalic Acid in Pairs in the Fixed-bed Electrolytic Cell

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As for the process of the electro oxidation of glyoxal to glyoxalic acid, the electrolytic result of either fixed bed electrolytic cell or varying current electrolysis was better than that of either flat plate electrolytic cell or constant current electrolysis. The average current density of varying current electro synthesis of glyoxalic acid in pairs was 1535 A/m 2 and the current efficiency were 85.3% and 86.7% and the selectivity were 93.9% and 94.0% for the anodic oxidation and cathodal reduction respectively. The initial composition of anodic electrolyte was 7% glyoxal and 8% hydrochloric acid (W/W) and the cathodal electrolyte consisted of saturated oxalic acid aqueous solution mixed with trace quantity of additive. The mass ratio of glyoxalic acid to glyoxal of the primary anodic product was over 40∶3, which avoided the separation of glyoxal from glyoxalic acid aqueous solution.作者联系地址：华东理工大学联合化学反应工程研究所反应工程国家重点实验室,华东理工大学联合化学反应工程研究所反应工程国家重点实验室,华东理工大学联合化学反应工程研究所反应工程国家重点实验室,华东理工大学联合化学反应工程研究所反应工程国家重点实验室 上海200237 ,上海200237 ,Author's Address: UNILAB Research Center of Chem. Reaction Engin., East China Univ. of Sci. and Tech., State Key Lab.for Reaction Engin., Shanghai 200237,Chin

Study of Electrolyzed Pure Iron and RRR_H Method

以工业废铁屑为原料制备高纯度电解铁 ,纯度可达 99.98%以上 .应用剩余电阻率比(RRRH)法 ,在外加垂直磁场 80 0 0e下分别测定该电解铁在 4 .2K和 2 98K时的电阻率 ,并得出样品对应的剩余电阻率比 (RRRH) .研究表明 :电解铁纯度越高 ,其RRRH 越大 .通过SEM断面形貌观察 ,在Ti基片上电解制备的纯铁非常致密The high purity electrolytic iron was made from scrap iron chips. The purity of electrolyzed pure iron was above 99.98% by chemical analysis. The resistivity was measured at 298 K and at 4.2 K under an applied longitudinal_magnetic field of 800 0 e. The ratio of resistivity at 298 K to that at 4.2 K, The value of residual resistivity ratio (RRR H) roughly depended on the purity of iron. Pure iron electrolyzed on Ti substrate had very compact texture as evident by SEM.作者联系地址：上海大学理学院化学系,上海大学理学院化学系,上海大学理学院化学系,上海大学理学院物理系,华东理工大学国家重点化学工程联合实验室 上海 ,上海 ,上海 ,上海200436 ,上海200237Author's Address: 1. Dept. Chem..Shanghai University, Shanghai 200436, China, 2. Dept. Phys. Shanghai University, Shanghai 200436, China, 3. China National United Engineering Laboratory ECUST.Shanghai 200237, Chin