A method and an apparatus for the production of industrial lead oxide involving mixing molten lead and air in a reactor. A particularly advantageous, having a desired particle size can be obtained with a PbO content of considerably more than 99%. The lead flow is introduced at a constant and even rate and the air flow is altered very slightly in order to maintain the pre-determined reaction temperature having fluctuations of a maximum of .+-.5.degree. C.The constant and steady infeed of the lead flow is achieved by using an apparatus according to the invention. The apparatus, which is situated above the reactor, includes a supply vessel charged with molten lead from a melt container, the supply vessel having an exchangeable nozzle which is provided with a control-operated cleaning pin. The nozzle extends into a reaction space and the supply vessel is connected to the melt container via a feed line and an overflow. The nozzle can also be of a known spray nozzle type which is fed with heated compressed air via a line running through the said melt container.