simplified Construction of Electrochemical Cells Often a. complex cell design is required to carry out a laboratory-scale electrosynthesis. This note recommends the use of inert plastic materials for construction of such cells. The complexity of the finished cell has been found to belimited only by the imagination and ingenuity of the designer, sincevery little skill is required. Most electrochemical cells me constructed in a manner such that the anode and cathode reactions proceed in separate compartments. In this way the stsrting material or the product formed at the working electrode (where the process of interest occurs) is protected from oxidation or reduction at the auxiliary electrode. Generally a porou5 porcelain cup (AlundumR)' serves adequately as a protective separator. Another design employs two glass containers (beakers or flasks) separated by a. medium porosity sintered glass disc (a so-called H-cell). A third type of construction uses an ion-exchange membrane as the separator in an H-cell or in a plat,e-and-frame ceL2 Polyethylene and polypropylene have been found by the author to be excellent, inexpensive materials of construction. These plastics are highly inert to most chemical reagents, solvents, and reaction conditions that are normally encountered, and are superior to glass in the presence of strongly alkaline solutianr. Conveniently, many shapes and sizes of containers, tubing, sheets, rods, and porous materials are abundantly aveilshle. Cells may he rapidly constructed using afine-tipped soldering iron and a heat gun as tools for welding and shaping. For example H-cells have been made of polyethylene bottles or jars (the screw caps make excellent closures), polyethylene tubing, and either porous po1yethylene"or ion-exchange membranes having a polyethylene support.' The bottles, tubing, and separator are readily welded together to provide leak-free gas-tight seals. In addition, solid eledrodes supported in inert plastic by meens of electrode-plastic seals, and cells with isolated reference electrode compartments can beeasily fashioned withlittle experience. Norton Company, Worcester, Mass. 01606.
C. L.,C h m Eng., 128 (1967); BECK,F.,AND GUTHKII., GO~DRIDGE, F., Chem. Process Eng., 93 (1968); MANTELL, , E., A N D WEINBERG, N. L., Chem. and Eng. News, 49, 40 (1971). H., Chem. Ing. Tech., 41 943 (1969). E s m s o ~ L. a
Bel-Art Products, Pequrtnnock, N. J. 07440.
'American Machine & Foundry Co., 689 Hope Street, Springdale, Conn. 06879.
N. L. WEINBERG
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Chemical Education
