Electrode

Abstract

The invention relates to a method for preparing a substantially lead-free turbulence promoting electrode, wherein an amount of turbulence promoting particles having a particle size from about 30 to about 2000 μm are contacted with at least one electrode and brought to adhere thereto, such that from about 5 to about 50% of the projected electrode surface area is covered with the particles. The invention also relates to a turbulence promoting electrode obtainable by the method and an electrode comprising turbulence promoting elevated parts arranged on at least one surface of the electrode. The height of the elevated parts is from about 30 to about 2000 μm. The invention further relates to the use of the electrode in an electrolytic cell for the production of alkali metal chlorate and alkali metal hydroxide.

1 . Method for preparing a turbulence promoting electrode comprising contacting an amount of turbulence promoting particles having a particle size from about 30 to about 2000 μm with at least one substantially lead-free electrode and bringing said turbulence promoting particles to adhere to said substantially lead-free electrode, such that from about 5 to about 50% of the projected electrode surface area is covered with said turbulence promoting particles.  
     
     
         2 . Method according to  claim 1 , wherein the particles are pressed into the electrode such that the particles are partly embedded in the electrode.  
     
     
         3 . Method according to  claim 1 , wherein the particles are contacted with the electrode by applying a particle containing coating solution.  
     
     
         4 . Method according to  claim 1 , wherein the particles have a particle size from about 50 to about 500 μm.  
     
     
         5 . Method according to  claim 1 , wherein the particles are made of a material selected from the group consisting of metal oxides, metals, ceramics, plastics, polymers and mixtures thereof.  
     
     
         6 . Method according to  claim 1 , wherein the particles are brought to adhere in substantially parallel lines to the electrode.  
     
     
         7 . Turbulence promoting electrode obtained by contacting an amount of turbulence promoting particles having a particle size from about 30 to about 2000 μm with at least one substantially lead-free electrode and bringing said turbulence promoting particles to adhere to said substantially lead-free electrode, such that from about 5 to about 50% of the projected electrode surface area is covered with said turbulence promoting particles.  
     
     
         8 . Turbulence promoting electrode having turbulence promoting elevated parts on at least one surface of a substantially lead-free electrode, said turbulence promoting elevated parts having a height from about 30 to about 2000 μm above said at least one surface.  
     
     
         9 . Electrode according to  claim 8 , wherein the elevated parts have dimensions in the plane of the electrode surface from about 30 to about 2000 μm.  
     
     
         10 . Electrode according to  claim 8 , wherein the electrode has from about 0.5 to about 150 million elevated parts/m 2  of the projected electrode surface area.  
     
     
         11 . Electrode according to  claim 8 , wherein the elevated parts cover from about 5 to about 50% of the projected electrode surface area.  
     
     
         12 . Electrode according to  claim 8 , wherein the elevated parts are turbulence promoting particles.