The Electrical Purification of Water

Abstract

The large scale electrical purification of water in the three-compartment cell is not satisfactory on account of the high cost of diaphragms. A new one-compartment cell was devised based on the direct electrolysis of water with but little electro-osmotic effect. Water with 150 to 600 mg./L. of salt and even more can be readily purified, the product analyzing 6 to 9 mg./L. salt. The new cell embodies two diaphragms. One of these is made of ceramic material and the other of asbestos.[Purification of water by distillation involves the conversion of the entire mass of water into steam and then condensing it again to liquid water. Since the amount of dissolved substances is usually very small, in most cases only 0.2 to 1.0 per cent of the water, seldom more than 1 per cent, it would seem to be more rational to carry out the purification by removing the small quantity of dissolved substances without touching the large mass of water. If the impurities are electrolytes, which is usually the case, then it is possible to apply electrical methods.The classic experiments of Hittorf on transference numbers demonstrated that the concentration of electrolytes, separated by a diaphragm, is altered upon passage of an electric current.The first suggestion of using a two-diaphragm, three-compartment cell to eliminate electrically dissolved or suspended constituents from liquids was made, probably at about the same time, by Siemens and Halske (Abel) 8 on the one hand, and by Morse and Pierce 4 on the other. ). Also electrodialysis is discussed by Dhiri, Lisbonne Kopaczewski, Pauli and others (see Abderhalden, Handb. d. biolog. Arbeitsmethoden Abt. III); Ind. Eng. Chem., 22, 1020Chem., 22, (1930, by E. Bartow and R. H. #ebene. 217 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 130.126.162.126 Downloaded on 2015-03-13 to IP ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to EC...

Lead Storage Battery Oxides with Metallic Additions

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