还原法制备芳香胺的研究进展

介绍了芳硝基化合物还原制备芳香胺的主要方法以及各还原方法在芳硝基化合物还原中的应用。芳硝基化合物还原制备芳香胺的方法主要有催化加氢法、金属还原法、水合肼还原法、硫化碱还原法、电化学还原法、催化氢转移法、光催化还原法、葡萄糖还原法、酶催化还原法等。其中光催化还原法和还原酶还原法反应条件温和、符合有机化合物转化过程中所追求的环保"良性"与"绿色"的目标,具有很高的研究应用价值。     

还原法制备芳香胺的研究进展

介绍了芳硝基化合物还原制备芳香胺的主要方法以及各还原方法在芳硝基化合物还原中的应用。芳硝基化合物还原制备芳香胺的方法主要有催化加氢法、金属还原法、水合肼还原法、硫化碱还原法、电化学还原法、催化氢转移法、光催化还原法、葡萄糖还原法、酶催化还原法等。其中光催化还原法和还原酶还原法反应条件温和、符合有机化合物转化过程中所追求的环保"良性"与"绿色"的目标,具有很高的研究应用价值。     

硝基芳香化合物废水处理技术研究进展

硝基芳香化合物是一类广泛应用于工业生产的工业化学品，具有生物毒性强、成分复杂、稳定性高等特点，若硝基芳香化合物废水直接进入环境将会对动植物及生态环境造成极大危害。从物理法（吸附法、萃取法、膜分离法）、化学法（电解法、Fenton法、臭氧氧化法、光催化法、膜催化法、湿法氧化法）、生物法（厌氧生物处理、好氧生物处理）、组合工艺4个方面，系统阐述了目前硝基芳香化合物废水处理技术的研究进展；结合最新研究报道以及相关实例，解析现有硝基芳香化合物废水处理技术的优缺点以及未来发展趋势；最后，根据硝基芳香化合物废水特性以及处理现状对未来的研究方向进行了展望，以期为针对硝基芳香化合物废水开发低成本、高效率、综合处理的新型处理技术提供科学依据和参考。     

4-氨基吡啶合成过程的绿色评价

采用原子利用率、环境因子和环境商以及GREENSCOPE法对4-氨基吡啶的不同合成工艺过程进行了绿色评价. 与传统的铁粉还原和催化氢化过程相比,电化学还原方法具有明显的优势：工艺操作简单,反应收率高,生产成本低,具有环境友好和可持续性. 采用电化学方法还原硝基化合物制备氨基化合物符合绿色化学发展的趋势,满足可持续发展要求,在精细化工领域具有良好的应用前景.     

对称席夫碱锌卟啉化合物的合成及性能研究

以乳酸、对硝基苯甲醛和吡咯为主要原料,硝基苯为溶剂合成meso-四(4-硝基)苯基卟啉化合物,通过浓盐酸和氯化亚锡还原得到对应的氨基卟啉,与锌配位后,在四氢呋喃为溶剂,冰醋酸为催化剂的作用下,与3种醛反应合成3种标题化合物。利用核磁共振氢谱,IR,UV-Vis,荧光,循环伏安法等方法确定了目标化合物的结构、光谱特征和电化学性能。讨论了不同给电子基团的引入对光谱性能及氧化还原能力的影响。     

基于Ti/SnO2阳极的电化学法降解对硝基苯酚

为探寻硝基芳香族有机污染物的高效降解技术,采用溶胶凝胶法制备了钛基锡系阳极,且掺杂Sb、La等元素对该电极材料进行了改性,并把该系列电极用于电化学处理模拟对硝基苯酚废水。通过SEM和XRD对电极形貌进行表征,分析了元素掺杂改善电极性能的机理,考察了电解条件对电化学降解对硝基苯酚效果的影响,探究了电场因素对电化学体系降解废水的影响机制。通过紫外吸收光谱分析推断了对硝基苯酚在电化学作用下可能的降解历程。研究结果表明：同时掺杂La和Sb的电极降解对硝基苯酚效果最好;在电解电压12 V、极板间距25 mm、pH值为7、电解质浓度0.5 mol/L的条件下电解120 min,对硝基苯酚的降解率可达92.8%,可见应用掺杂La、Sb的Ti/SnO2电极材料的电化学法降解对硝基苯酚优势相当明显。     

用生化法处理含硝基和氨基物废水

吉林染料厂在生产硝基和氨基化合物过程中产生大量工业污水,严重的污染了江河。为了解决污染问题,我们从去年十月份开始了污水处理试验。我们首先抓了毒性较大的含硝基和氨基化合物的污水处理问题。通过半年多的小试验及模型试验,用生化法处理含硝基和氨基化合物的污水试验,     

石墨烯在对硝基苯酚电化学法检测中的应用

对硝基苯酚是一种高毒性污染物,它的有效检测对人们的健康以及环境的保护具有重大的意义。在众多的检测方法中,电化学方法因其灵敏度高、设备简单、检测快速等优势被广泛应用。此外,石墨烯因其优异的电化学性能而被用于电化学传感器。综述了石墨烯修饰电极材料在对硝基苯酚电化学法检测中的应用研究进展。     

2,2-二硝基丁醇的合成及其应用

偕二硝基类化合物是一种化学性能优良、热稳定性好的含能材料。2,2–二硝基丁醇(DNBOH)是合成偕二硝基类含能材料的重要中间体之一。介绍了DNBOH的几种合成方法:氯化硝化法、硝酸银氧化硝化法、新型氧化硝化法和电化学法。分析比较了各种方法的优缺点。结果表明,新型氧化硝化法是一种成本低廉、环境友好的合成方法,电化学法减少了原料的用量,降低了三废的处理量,具有较好的研究价值和应用前景。介绍了DNBOH在合成新型含能增塑剂和黏合剂方面的应用。     

加氢催化还原芳硝基制芳胺催化剂的研究进展

介绍了芳硝基化合物还原制备芳香胺的方法,主要包括催化加氢还原法、CO还原法、金属还原法、硫化碱还原法、金属氢化物还原法、水合肼还原法、电化学还原法、生物法及光催化等,指出催化加氢还原法是制备芳胺的有效方法。综述了芳硝基加氢还原催化剂的研究进展,对镍、钯、铂、金及一些非金属催化剂的应用研究进行了述评,同时指出,催化加氢还原法制备芳胺催化剂未来的研究方向和重点是开发环境友好型非金属催化剂、新型催化剂载体以及进一步提高金属催化剂的重复利用率和活性,降低催化剂成本。     

Electrochemical polymerization of 1,2-ethanedithiol as a new way to synthesize polyethylenedisulfide

Preliminary studies of the electrochemical oxidation of 1,2-ethanedithiol in acetonitrile at platinum electrode surfaces are presented. A permanent modification of the electrode surfaces was observed after the anodic oxidation of 1,2-ethanedithiol. This modification is due to the formation of an organic polymer coating strongly tied to the electrode surfaces. This electrochemical polymerization process was studied by coupling electrochemistry and in situ electrochemical quartz crystal microbalance experiments, while ex situ X-ray photoelectron spectroscopy, Raman spectroscopy and Infrared spectroscopy were used to determine the structure of the polymer film. These spectroscopic techniques allowed us to identify the polymer films obtained by oxidation of 1,2-ethanedithiol as polyethylenedisulfide films.     

X-ray voltabsorptometry on redox proteins

Biological X-ray absorption spectroscopy (BioXAS) is able to describe the metal environment in a metalloprotein and is sensitive to metal oxidation state. Coupling of BioXAS and electrochemistry permits the characterization of different oxidation states and avoids uncontrolled protein redox state changes due to X-ray beam irradiation. XAS spectroelectrochemistry requires electrochemical cells specifically designed to meet the requirements of both XAS measurements and electrochemical effectiveness in potential control. In this context, this paper describes a new cell tested with different types of working electrodes developed for BioXAS, in particular for in situ studies of redox proteins. The XAS electrochemical measurements of a relatively high-molecular-weight protein (Cu,Zn superoxide dismutase) for which it is difficult to observe direct electrochemistry have been achieved.New working electrodes, capable of fast and unmediated electron transfer, are described. The cell permits to isolate protein redox states and to measure X-ray absorption intensity during a potential scan (X-ray voltabsorptometry).     

Direct electrochemistry of double strand DNA on ionic liquid modified screen-printed graphite electrode

An ionic liquid modified screen-printed graphite electrode (SPE) was used for direct electrochemistry of herring sperm double strand DNA (dsDNA) by voltammetry. Due to the high conductivity of ionic liquid n-octylpyridinum hexafluorophosphate (OPPF), this electrode exhibited excellent electrochemical activity for the oxidation of dsDNA. Two irreversible oxidation peaks were obtained at the developed electrode, which corresponded to the oxidation of guanine and adenine residues present in the dsDNA. The basic electrochemical behavior of dsDNA at the OPPF modified SPE was carefully investigated. Combined with the differential pulse voltammetry, this electrode exhibited a good linear range from 20 μg mL⁻¹ to 120 μg mL⁻¹ with a detection limit of 5 μg mL⁻¹ for the direct determination of dsDNA. Furthermore, the OPPF modified electrode displayed high reproducibility and stability for the dsDNA determination.     

Electrochimie des composes organometalliques des metaux de transition

Electrochemical results obtained on transition metals organomettalic compounds during the period 1950–1976 are presented with 290 references. Attempt is made to put together the known mechanistic informations on the electrolytic processes both for oxidation and reduction. This review shows that most of the experimental studies have been carried out on the electrochemical reductions and that there is a lack of anodic studies in the promising field of unstable low oxidation state of transition metals. The reviewed electrochemical studies were generally undertaken to elucidate the redox mechanisms, and to obtain kinetic informations on the different steps of the overall process. The problem of determining the molecular orbital involved in the electron transfer is in most cases not solved. Metallocenes, carbonyl metal are the subject of numerous papers, but only few publications are devoted to electrochemistry of metallocarborans, carbyns, ylids and clusters. In a second part of this review is developed a very important application of the electrochemistry, the electrosynthesis of metal complexes. Examples are chosen to illustrate the specific possibilities offered by this method and special attention is given to in situ electrochemical generation of orgnanomettalic catalysts, a route to polymerization and oligomerization in organic synthesis.     

Solid electrochemical mass spectrometry (SEMS) for investigation of supported metal catalysts under high vacuum

A new experimental set-up, coupling electrochemistry and mass spectroscopic techniques, for the investigation of a solid electrochemical cell under high vacuum conditions (HV) is presented. Two configurations are realized allowing the investigation of both the electrochemical and electrocatalytical behavior of a thin Pt layer on yttria stabilized zirconia (YSZ). We can readily select the atmosphere down to 10⁻⁶ Pa partial pressure and determine the response of the system in less than 1 s. Under HV conditions, YSZ appears electrochemically active and we have identified, in the cathodic potential domain, the reduction/oxidation process of zirconia and in the anodic domain, the platinum oxidation/reduction and the oxygen evolution reactions. In a catalytic active gas mixture, despite the Faradaic enhancement of the CO oxidation observed over Pt/YSZ during an anodic polarization, an intriguing sustainable enhanced Pt/YSZ catalyst activity is achieved after current interruption.     

Applications of surface X-ray scattering to electrochemistry problems

Applications of the synchrotron X-ray scattering technique to electrochemistry problems are briefly reviewed ranging from submonolayer level phenomena, through nanometer size phenomena, to submicron size phenomena; that is, covering the full range of the ‘interphase’ at an electrode surface. The examples include, (i) incipient oxidation/reduction of platinum single crystal surfaces; (ii) submonolayer/monolayer level oxidation/reduction of ruthenium dioxide single crystal surfaces; (iii) copper passivation/depassivation; and (iv) anodic formation of porous silicon and silicon dioxide layers. The design of several X-ray/electrochemical cells is also described.     

Electrochemistry and determination of epinephrine using a mesoporous Al-incorporated SiO2 modified electrode

The potential application of Al-incorporated mesoporous SiO₂ (denoted as Al-MCM-41) in electrochemistry as a novel electrode material was investigated. The peak currents of K₃[Fe(CN)₆] remarkably increase and the peak potential separation obviously decreases at the mesoporous Al-MCM-41 modified carbon paste electrode (CPE). These phenomena suggest that the mesoporous Al-MCM-41 modified CPE possesses larger electrode area and electron transfer rate constant. Furthermore, the electrochemical behavior of epinephrine (EP) was investigated in different supporting electrolytes such as 0.01 mol L⁻¹ HClO₄ and pH 7.0 phosphate buffer. It is found that the mesoporous Al-MCM-41 modified CPE exhibits catalytic ability to the oxidation of EP due to remarkable peak current enhancement and negative shift of peak potential. The electrochemical oxidation mechanism was also discussed. Finally, a novel electrochemical method was proposed for the determination of EP, which used to determine EP in urine samples.     

Electrochemistry of the biliverdin—bilirubin system in N,N-dimethylformamide

The electrochemical behaviour of biliverdin and bilirubin on platinum electrodes in N, N-dimethylformamide has been investigated by means of voltammetric as well as controlled-potential electrolysis techniques.Bilirubin can be oxidized to biliverdin and the latter, in turn, to further oxidation products; conversely, biliverdin can be reduced to bilirubin, and the latter to further reduction products: however, the potential for the anodic oxidation of bilirubin to biliverdin and that for the cathodic reduction of biliverdin to bilirubin are about 1.6 V apart from each other. The reduction of biliverdin to bilirubin is shown to be amenable to preparative electrochemistry.     

6-硝基胡椒基酸合成新方法

报道了直接以黄樟油为原料,经硝化和氧化制备6 硝基胡椒基酸的新工艺。采用调整反应温度和硝酸浓度等因素对硝化反应进行了探讨;采用正交实验优化了氧化反应参数,获得了较好的工艺条件。     

Voltammetric determination of the critical micellar concentration of surfactants by using a boron doped diamond anode

The electrochemistry of three surfactants has been studied by voltammetry at boron doped diamond (BDD) electrode in sodium sulphate solutions. The electrochemical behaviour of these surfactants is characterized by an oxidation signal (peak or wave) situated before the electrolyte oxidation. The anodic current is found to follow a linear relation with the concentration of the surfactants; the slope decreases abruptly above the critical micellar concentration (CMC) of the surfactants. The CMC values obtained for an anionic (sodium dodecylbenzenesulfonate, SDBS), a cationic (polyoxyethylene-23-dodecyl ether, BRIJ 35) and a neutral (1-(hexadecyl)trimethylammonium bromide, CTAB) surfactant are found in good agreement with those measured by the classical technique of surface tension. This voltammetric method has the advantage not to require the use of a redox active electrochemical probe.