Flow-through anodic stripping

Beinrohr E, Tschopel P, Tolg G, Nemeth M (1993) Flow-through anodic stripping coulom-etry and anodic stripping coulometry with collection for the simultaneous determination of copper, lead, cadmium, and zinc. Anal Chim Acta 273 13-25... 

Side-by-side streaming, T shape, channel length =12 mm, channel height = 0.3 mm, channel width = 3 mm, electrodeposited Pd and Au on carbon paper strips to make flow-through anode and cathode, fuel utilization of 85% at peak power density and 100% at lower voltages Air-breathing electrode... 

Qin, W., Zhang, Z., and Liu, H., Chemiluminescence flow-through sensor for copper based on anodic stripping voltammetric flow cell and ion-exchange column with immobilized reagents., Anal. Chem., 70, 3579, 1998. 

The copper flow-through CL sensor comprised an anion-exchange column having luminol and cyanide coimmobilized on the resin, while copper was temporarily retained by electrochemical preconcentration on a Au electrode placed in an anodic stripping voltammetric cell [64], Injection of 0.1 mol/L NaOH through the column eluted the reagents, which then reacted with copper, stripped from the electrode to produce a CL signal. The response was linear in the 0.01-10-pg/L... 

Any type of detector with a flow-through cell can be used for FIA. Photometric detectors are most often used in FIA (15-18, 25). However, many other analyses using fluorimeters (28, 29), refractometers (24), atomic absorption (30, 31), and inductively coupled plasma emission spectrometers (32) have been described. Electrochemical detectors based on potentiometry with ion-selective electrodes (15, 33), anodic stripping voltammetry (15, 34), potentiometric stripping (35), and amperometry (36) have also been used. 

An electrolysis cell contains a solution of 0.10 M NiS04. The anode and cathode are both strips of Pt foil. Another electrolysis cell contains the same solution, but the electrodes are strips of Ni foil. In each case a current of 0.10 A flows through the cell for 10 hours. 

Wet AgCl is a solid ionic conductor. With DC current flow, the AgCl layer will increase in thickness if it is deposited on silver metal anode. The polarization impedance will go through a minimum and thereafter increase as a function of AgCl-layer thickness (see the following section). As a cathode with DC current flow, the layer will diminish and eventually be stripped of. We are left with a pure silver surface with quite different properties (e.g., with much higher polarization impedance and a different equilibrium potential) (Figure 7.3). 

The gaseous UFe is reduced by bubbling it with an excess of hydrogen through fresh molten fluoride salt. The resultant UF4 is trapped in this clean salt melt. As shown in Fig. 24-18, the salt containing UF4 is next contacted with the stripped bismuth stream in an electrochemical reduction step. In this step, the UF4 is reduced to metal at a flowing bismuth cathode while fluorine gas is released at the anode. The resultant bismuth-uranium alloy, to which Mg and Zr have previously been added, is ready for re-entry to the core. 

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