Pollutants electrochemical analysis

Hansen HK, Ottosen LM, Lauesen S and ViL-lumsen a (1997) Electrochemical analysis of ion-exchange membranes with respect to a possible use in electrodialytic decontamination of soil polluted with heavy metals. Separation Sci Technol 32 2425 — 2444. 

Smyth WF, Smyth MR. 1987. Electrochemical analysis of organic pollutants. Pure AppI Chem 59(2) 245-256. 

A comprehensive account up to 1970 of the electroanalysis of agrochemicals is given in the book by Nangniot. Birch and Hart reviewed papers until 1979. The recent review by Smyth and Smyth Electrochemical Analysis of Organic Pollutants provides numerous modern references in this field. 

W. F. Smyth. M. Smyth Electrochemical Analysis of Organic Pollutants." Pure Appl. Chem. 59 (1987) 245. 

Other Inorganic Pollutants Electrochemical sensors are commonly applied to water analysis. The Standard Methods for the Examination of Water and Wastewater [20] include the following approved by EPA... 

Craffeo AP, Riggin RM. 1978. The application of electrochemical detection to the HPLC analysis of nonvolatile pollutants. In Proceedings 4th joint conference on Sensory Environmental Pollution, 637-639. 

Because of their chemical stability and past industrial applications, PCBs are ubiquitous contaminants in the environment marine sediment, soil and food are the matrices where the presence of PCBs is more documented. For their characteristics electrochemical immunosensors are valid analytical tools to carry out a fast screening analysis on a large number of potentially polluted samples. 

Porous metallic structures have been used for electrocatalysis (Chen and Lasia, 1991 Kallenberg et al., 2007). Porous electrodes are made with conductive materials that can degrade under high temperatures at high anodic potential conditions. This last problem is of less importance for fuel cell anodes, which operate at relatively low potentials, but it can be of importance for electrochemical reactors. Porous column electrodes prepared by packing a conductive material (carbon fiber, metal shot) forming a bar are frequently used. Continuous-flow column electrolytic procedures can provide high efficiencies for electrosynthesis or removal of pollutants in industrial situations. Theoretical analysis for the electrodeposition of metals on porous solids has been provided by Masliy et al. (2008). 

Wastewater contains in general a variety of organic pollutants. Analysis of these pollutants and their oxidation products during the electrochemical treatment is not only a complex matter but does not give direct informations about the current efficiency and the oxidation state of the organic carbon during treatment. 

The nature of organic pollutant influences strongly the EOI values. In this paper the influence of benzene derivatives on the EOI value has been studied using a Pt anode. Effort has been made to treat the experimental EOI data by correlation analysis [the term "Quantitative Structure - Electrochemical Activity Relationship" (QSEAR) was used for this approach] using the equation... 

Fundamentally, trace analysis is possible with a range of different procedures. In the organic pollutant determination, chromatographic methods such as GC, GC-MS, HPLC and, more recently immunoassay and to a greater degree, the coupling of HPLC with electrochemical detection (HPLC-EC) (see below) take precedence (cf. )... 

In the book by Keith Identification and Analysis of Organic Pollutants in Air out of the 473 pages only a short chapter of 13 pages, reporting a preliminary study of the potential of electrochemical methods in the analysis of the mixtures of polycyclic aromatic compounds (PAG), is devoted to polarography and voltammetry. 

Electrochemical sensors, the most ancient of which is the electrode, are currently undergoing development in that their prices are often low, they are easy to use and, most of all, they are easy to insert into a regulation system. In this respect, the most widely used today is the dioxygen sensor, which allows for combustion to be optimised thanks to the process of analysing the exhaust gases . Several million parts per year are produced, notably for the car industry. In the biomedical field, electrochemical sensors are also used to monitor glucose and pH, and to measure out certain cations. New developments are also being made in the field of pollutant analysis. 

To overcome the problem of detection in CE, many workers have used inductively coupled plasma-mass spectrometry (ICP-MS) as the method of detection. Electrochemical detection in CE includes conductivity, amperometry, and potentiometry detection. The detection limit of amperometric detectors has been reported to be up to 10 M. A special design of the conductivity ceU has been described by many workers. The pulsed-amperometric and cyclic voltametry waveforms, as well as multi step wave forms, have been used as detection systems for various pollutants. Potentiometric detection in CE was first introduced in 1991 and was further developed by various workers. 8-Hydroxyquinoline-5-sulfonic acid and lumogallion exhibit fluorescent properties and, hence, have been used for metal ion detection in CE by fluorescence detectors. Overall, fluorescence detectors have not yet received wide acceptance in CE for metal ions analysis, although their gains in sensitivity and selectivity over photometric detectors are significant. Moreover, these detectors are also commercially available. Some other devices, such as chemiluminescence, atomic emission spectrometry (AES), refractive index, radioactivity, and X-ray diffraction, have also been used as detectors in CE for metal ions analysis, but their use is stiU limited. 

Major areas of electrochemical measurements with CPEs (in order of appearance) (1) Electrode reaction pathways and mechanisms of electroactive organic compounds (see also Figure 11.3a-d) (II) Pharmaceutical and clinical analysis (III) Solid-phase voltammetry with electroactive CPEs (IV) Analysis of (i) inorganic ions and molecules, (ii) organic compounds -i- environmental pollutants, and (iii) analysis of biologically important compounds (BICs) (V) Voltammetry in vivo (also known as brain electrochemistry). 

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