How is caustic potash made?
Caustic potash is made in a process known as
which also produces chlorine and hydrogen as co-products. Electrolysis is a chemical process which uses electricity to split salt and water into chlorine, caustic and hydrogen. This takes place in an electrolyser. An electrolyser is made up of a positive electrode (or anode), a negative electrode (a cathode). These electrodes are sat in salt water with the two electrodes being separated by a semi-permeable ‘barrier’ (also known as a membrane or a diaphragm). This barrier keeps the caustic soda safely separate from the chlorine.
