Abstract: An apparatus for rinsing liquid medium is described, the apparatus is an electrochemical cell comprising an anode with a precious metal and at least one cathode made of a non-metallic support material in the form of fibre positioned to form a mesh or a felted mat. The support material of the cathode is treated with a metal. When the electrochemical cell is in function, compounds and/or particles of a liquid to treat are deposited on the mat(s) functioning as the cathodes. The cathodes are easily replaced e.g. when no more compounds can be deposited on the mat. Pure samples of metals can be obtained by burning away the support material of the cathodes. The electrochemical cell is especially suitable to treat water including process water, waste water, and ground water.