摘要:
A process is disclosed for coloring building materials with inorganic pigments in the form of microgranulates. The granulates comprise one or more pigments and one or more compounds selected from boron, aluminum, silicon, titanium, zinc and tin.
摘要:
Needle shaped alloy pigment powders consisting essentially of iron, silicon and aluminum, with up to 1.0% by weight of chromium and one or both of cobalt or tin in amounts from 0.3 to 3% by weight of cobalt and from 0.1 to 5.0% by weight of tin, based in each case on the iron, are useful as the magnetic powders used in magnetic recording devices.
摘要:
In a rotary tubular kiln for carrying out gas-solids reactions, comprising an indirectly heated, rotatable reaction tube with inner baffles which is provided with charging and removing devices for solid and gas inlet and outlet lines, the improvement which comprises forming the baffles as a central tube which is sealed on both sides and runs along the total length of the kiln, and a spiral which is tightly connected to the central tube and also to the outer rotatable tube. Lifting blades are uniformly distributed along the inner periphery of the rotatable tube. The kiln is suitable for carrying out oxidation, reduction, chlorination, roasting, decomposition, catalytic, annealling and/or cooling processes, e.g. the conversion of hematite to magnetite or goethite to iron.
摘要:
Spherical agglomerates of surface-stabilized primary particles substantially consisting of iron, having a BET surface of about 5 to 50 m.sup.2 /g, measured on the agglomerate, in non-pyrophoric form and having a bulk density of about 0.5 to 2.0 kg/l and an agglomerate diameter of about 0.5 to 10 mm are produced by(a) reducing in dry phase particles consisting essentially of iron oxide,(b) intensively dispersing the particles in liquid phase,(c) coating the particles with an inorganic and/or organic coating optionally containing corrosion inhibitors,(d) separating the particles from the liquid phase by evaporating the volatile components with a continuously rotating and simultaneously tumbling movement, and(e) subjecting the resulting granulates to a thermal treatment. The particles are especially useful for the production of magnetic recording media.
摘要:
Chrome green oxide useful, inter alia, as a coloring material and having a water number of 10 to 40 g/100 g is prepared by adding sulphonic acid compounds, polyphosphoric acid compounds, polyacrylic acid compounds or mixtures thereof, in quantities of from 0.1 to 2% by weight, to an aqueous suspension of chrome oxide green pigment having a BET surface area of from 1 to 20 m.sup.2 /g before drying, and then drying the suspension.
摘要:
A process for the production of rutile mixed-phase pigments comprising calcinating of a solid mixture of titanium dioxide or titanium oxide hydroxide with a dye-producing compound of a metal, in one or more directly heated, continuously operated rotary kilns, wherein in terms of material flow, air is introduced into the kiln atmosphere countercurrently to the direction of flow of the solids in the second half of the rotary kiln.
摘要:
In a rotary tubular kiln for carrying out gas-solids reactions, comprising an indirectly heated, rotatable reaction tube with inner baffles which is provided with charging and removing devices for solid and gas inlet and outlet lines, the improvement which comprises forming the baffles as a central tube which is sealed on both sides and runs along the total length of the kiln, and a spiral which is tightly connected to the central tube and also to the outer rotatable tube. Lifting blades are uniformly distributed along the inner periphery of the rotatable tube. The kiln is suitable for carrying out oxidation, reduction, chlorination, roasting, decomposition, catalytic, annealing and/or cooling processes, e.g. the conversion of hematite to magnetite or goethite to iron.
摘要:
A white composite pigment, containing isometric rutile pigment particles and acicular modified potassium hexatitanate, is produced by reacting titanium dioxide or a titanium compound which can be converted into titanium dioxide under the reaction conditions in the presence of rutile seeds with a potassium compound which reacts basically under the reaction conditions, a mineralizer and a polyvalent metal fluoride at a temperature of about 700.degree. to 1100.degree.C.
摘要:
Iron oxide black pigments useful as coloring pigments for lacquers and plastics are prepared by an improved process wherein finely divided iron oxide black suspensions obtained from the precipitation processor the aniline process are filtered, washed, dried and ground with the improvement in the process comprising grinding the dried iron oxide pigment in a jet mill with air as the grinding medium and with a water content of from about 1 to 6% by weight based on the iron oxide black pigment input to the process.
摘要:
A process for the production of rutile mixed-phase pigments comprising calcinating a solid mixture of titanium dioxide and/or titanium dioxide hydrate with a dye-producing metal compound in an indirectly heated rotary kiln supplied with air, wherein the titanium dioxide comprises an uncalcined, salt-free titanium dioxide having a specific BET surface of 50 to 500 m.sup.2 /g.