Carbonaceous materials used in the production of aluminium — Pitch for electrodes — Determination of ash

A test portion is deated in a tared platinum crucible, in a furnace at 700 degrees centigrade, under oxidizing and specified conditions, to constant mass. The residue is cooles and weighed. The method is applicable to products (tar pitch, petroleum pitch, etc.) producing a quality of ash greater than or equal to 0,05 % (m/m).