摘要:
The invention concerns a process for the preparation of alumina and ferric oxide from low-grade aluminium and iron carriers. The processes, in addition to conventional technological steps, comprises the steps of dissolving the iron content of a ground, mineral material in an aqueous hydrochloric acid solution containing 200 to 420 g./lit. of hydrochloric acid at 90.degree. to 130.degree. C., eliminating the iron from the slurry of from a solution obtained by filtration of the slurry, with an anion exchange resin or semipermeable membrane or cloth, continuously or discontinuously, eluting the iron from the ion exchange resin and recycling hydrochloric acid and sulfuric acid in a closed system.
摘要:
The invention relates to an improved process for reducing the iron content of iron-, silicon- and aluminium-containing raw materials and for producing ferric oxide, optionally along with an alumina concentrate. According to the invention the iron content of mineral raw materials, e.g. bauxites, clay minerals, colliary rocks, red muds, etc. is eliminated by passing through one or more beds prepared from the unground but preferably prebroaken and sized raw material an aqueous hydrochloric acid solution, the concentration of which exceeds 100 g./lit., at a temperature below 90.degree. C., preferably at room temperature, optionally in the presence of a flocculating agent. By pyrolytic decomposition of the ferric chloride prepared ferric oxide can be produced. The bed residue of reduced iron content can be utilized in the Bayer process for producing alum earth, as a starting substance of ceramic industry or, after treating with sulfuric acid, dissolving in hydrochloric acid or water, elimination of silica, pyrolytic decomposition of the aluminium sulfate obtained, as an alumina concentrate.
摘要:
The invention relates to an improved method for the liquid phase oxidation of coal performed with oxygen optionally in the presence of water. According to the invention oxidation is performed in the presence of a cooxidation partner selected from the group of liquid hydrocarbons and oxygen-containing liquid hydrocarbons, and if water is also present, the pH of the homogeneous solution formed from the cooxidation partner and water is maintained at a slightly acidic value.By the method of the invention the formation of carbon dioxide can be suppressed significantly.
摘要:
The invention relates to an improved method for the production of liquid carbon compounds from coal. According to the invention coal is oxidized at 80.degree. to 300.degree. C. in the presence of the vapors of a C.sub.1-5 aliphatic alcohol, optionally under the introduction of steam, and then the liquid carbon compounds are separated from the resulting product mixture.The process according to the invention can also be performed under atmospheric pressure, 50-80% of the carbon content of the coal converted appear in the liquid product. The liquid product contains the more valuable fraction, boiling below 300.degree. C., as major component.
摘要:
The invention relates to a method for utilizing silicon tetrachloride formed as a by-product of the chlorination of aluminium- and silicon-containing minerals. More particularly, the invention relates to a process for the preparation of aluminium trichloride and silicon dioxide by chlorination of alumina with silicon tetrachloride. According to the invention alumina or a material essentially consisting of alumina is reacted with silicon tetrachloride as a single chlorinating agent at a temperature exceeding 400.degree. C., unreacted silicon tetrachloride is separated from the aluminium trichloride formed and is recycled into the chlorination step, silicon dioxide is isolated from the solid residue essentially consisting of the unreacted alumina and silicon dioxide, unreacted alumina is recycled into the chlorination step and aluminium trichlorine obtained is continuously eliminated.
摘要:
The instant invention is particularly useful for using low-grade carbonaceous material to form aluminum-trichloride. Aluminous material and the carbonaceous material are comminuted either separately or together, and then the aluminous and carbonaceous materials are either compacted or mixed with a binder to form a doughlike paste. The compacting or mixing with the binder to form the dough-like paste is to insure that the particulate aluminous and carbonaceous materials have extremely close and intimate contact. The mixture is then calcined and chlorinated at an elevated temperature to form aluminum trichloride.
摘要:
A process for the continuous preparation of silicon-base complex ferrous alloys from cheap raw materials by preparing a charge with a high electric resistance and reducing the same in an electric arc furnace. A charge is assembled which contains the total amount of carbon in a 0.82 to 0.99-fold quantity of that required to reduce all oxides of the charge to elements and achieving this carbon content by preparing pellets which, in addition to the binding material, contain(a) as oxide to be reduced in an amount of at least 50% by weight such oxides of only base-forming or only amphoteric or only acid-forming elements which form with each other compounds or eutectics melting above 1600.degree. C., and(b) a carbonaceous reducing agent and/or carbides in such an amount that the quantity of carbon is either 1.05 to 1.35 times higher than required to transform the oxides of the pellet to the carbides or 0.66 to 0.02-fold of the quantity required to reduce the oxides of the pellet to metallic elements, and assembling the charge(.alpha.) from pellets containing an excess of carbon and/or from lumpy carbides and(.beta.) from carbon-deficient pellets or from a lumpy oxide of a base-forming or amphoteric or acid-forming element and(.gamma.) from lumpy carbon carriers, and optionally(.delta.) from an iron additive, in the absence of boron trioxide.