Diaphragms for alkaline water electrolysis and method for production of

Abstract

A diaphragm of porous sinter material for alkaline water electrolysis characterized by a porous sinter metal oxidized at least partially to metal oxide. A frame structure of the sinter body is provided especially wire net. The base metal of the sinter body is formed by nickel, iron or copper. The method includes forming a porous metal sinter body and oxidizing the same at elevated temperature in oxygen-containing atmosphere. The method for production of nickel oxide diaphragms furthermore includes applying to a nickel net a pasty mass of nickel powder containing a binder and burning. Applying in a thin layer as by brushing nickel powder of a particle size of about 1 to 10 mm in a rubber solution in toluene upon a carrier, especially a nickel net, and this arrangement is subjected to sintering at 700.degree. to 1,000.degree. C. for a time or duration of 10 to 20 minutes in inert or reducing atmosphere especially in hydrogen and the sinter body which is obtained is subjected to roasting in air at 1000.degree. C. to 1200.degree. C. up to three hours, especially for a time duration in a range of between ten and forty minutes. The diaphragms are produced with a thickness in a range of approximately 1 mm, especially in a range of approximately 0.3 mm to 0.7 mm. Utilization of the diaphragm includes electrolysis cells with active porous nickel electrode fixed on the diaphragm in a sandwich manner of construction.