Abstract: Described is a method for the manufacture of a pastel-white, highly opaque, micro-particle rutile pigment from a crude rutile, synrutile or from a slag-like rutile-type precursor characteristic for traditional titanium dioxide production from processing ilmenite into titanium dioxide. This method distinguishes itself in that the starter material in form of the crude rutile, synrutile or the slag-like rutile-type precursor is ground down in several stages in high efficiency mills without leaving any significant metallic fines, to a particle size of approximately 200 to 600 nm, whereby initially a dry pre-grinding step is performed and thereafter with high recorded grinding output a wet grinding step is performed in a final grinding phase. The ground-down product is dried and the obtained rutile pigment is calcinated in finely distributed form at temperatures between 790 and 1050° C.

Abstract: This invention relates to a process for the accelerated production of red lead oxide, the lead oxide to be oxidized being kept in suspension like a fluidized bed, particularly being kept in suspension like a fluidized bed in a stirrer reactor by a stirrer, only part of the finished product being drawn off from the fully oxidized fluidized bed and being replaced by new lead oxide to be oxidized, as well as an apparatus therefor.

Abstract: The method according to the invention for producing industrial litharge of more than 99.98, preferably more than 99.99, % by weight oxide content, wherein liquid lead in heated form is introduced into a reactor in an amount which is constant and uniform in time average, the reaction temperature is set to a temperature in the range from more than 500.degree. C. to 680.degree. C. and the crude oxide having an oxidation degree of about 99.7% thus obtained is further oxidized, is characterized in that in the first stage in the production of the crude oxide with an oxidation degree of about 99.7% the product discharged with the reaction air is filtered out of the latter and returned to the reactor and, when enough oxide has collected in the reactor, the lead supply and the filter oxide return are interrupted and only air is then blown in, and the charge oxidized to a residual content of metallic lead of at the most 0.01% is not completely discharged but only to an extent of about 50%.

Abstract: 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.

Abstract: In a process and a device for manufacturing partially oxidized lead dust from lead pieces, the natural pile of dissociated coarse and fine material formed in a rotating drum is mechanically disturbed by radially extending guide plates in the interior of a drum which plates are arranged in pairs and displaced toward each other by 180.degree. in the direction of the circumference of the drum and the individual plates of each pair of plates are spaced axially apart, by which arrangement the efficiency of the process and the product quality are greatly improved.