Abstract: Process wherein the vanadium present in the chromium ore chromite is recovered as vanadium pentoxide during the course of the fusion of the chromium ore with alkali and its work-up to produce sodium chromate solution and sodium dichromate.

Abstract: Process for recovering the vanadium present in the chromium ore chromite, as vanadium pentoxide, as a by-product from the vanadium-containing sodium chromate solution produced in the process of preparing sodium chromate and sodium dichromate from said ore, by precipitation of calcium vanadate from the sodium chromate solution, treatment of the precipitate with water and sodium carbonate, sodium bicarbonate, carbon dioxide or sodium carbonate and carbon dioxide, to precipitate calcium carbonate and electrolysis of the solution remaining after separation of the calcium carbonate precipitate, to produce vanadium pentoxide.

Abstract: Process wherein the vanadium present in the chromium ore chromite is recovered as vanadium pentoxide during the course of the fusion of the chromium ore with alkali and its work-up to produce sodium chromate solution and sodium dichromate.

Abstract: The invention relates to a novel process for preparing fluorosulfonic acid having low contents of low-boiling compounds in which hydrogen fluoride and sulfur trioxide are combined in stoichiometric amounts in a reaction vessel or by means of a reaction nozzle, the hot, gaseous fluorosulfonic acid that is formed is fed directly into a distillation column, and the fluorosulfonic acid is taken off at the bottom of the column or in the stripping section of the distillation column.

Abstract: A process for recovering the vanadium present in the chromium ore chromite. as ammonium metavanadate, as a by-product of the fusion of the chromium ore with alkali and its work-up to produce sodium chromate solution and sodium dichromate.

Abstract: The invention relates to a novel process for preparing fluorosulfonic acid having low contents of low-boiling compounds in which hydrogen fluoride and sulfur trioxide are combined in stoichiometric amounts in a reaction vessel or by means of a reaction nozzle, the hot, gaseous fluorosulfonic acid that is formed is fed directly into a distillation column, and the fluorosulfonic acid is taken off at the bottom of the column or in the stripping section of the distillation column.

Abstract: A method for the decomposition of chromium ore in a directly heated revolving tube is described, in which oxygen-containing gases are introduced into the revolving tube by means of below-bed nozzles.

Abstract: A method for manufacturing alkali chromates by the reacting of chromium ore with alkali compounds and oxidation in an atmosphere containing at least 50% oxygen is described, in which the mixture consisting of chromium ore, alkali compound and optionally leaning materials is heated in a first stage in an atmosphere containing not more than 5 vol. % oxygen to a temperature between 1000.degree. and 1 400.degree. C., and in a second stage is oxidized at a lower temperature of 900.degree. to 1 070.degree. C. with supply of an atmosphere containing at least 50% oxygen.

Abstract: A process for the removal of organic impurities and dissolved salts from hydrazine hydrate and aqueous solutions thereof by distillation of the hydrazine hydrate under reduced pressure, passing the hydrazine hydrate vapor through an adsorbent, and condensing the vapor.