Abstract: A process is provided for preparing concentrated aqueous solutions of byproduct nitrate compounds from dilute aqueous streams containing said byproduct nitrate compounds, calcium ions and anionic species capable of reaction therewith at elevated temperatures. The process provides for the removal of the calcium ions by the addition of a source of carbonate ions to said stream to form solid, particulated calcium carbonate therein, the separation of the solid particulate from the stream, the neutralization of the stream and concentration of the stream to provide a concentrated aqueous solution containing the byproduct nitrate compound.

Abstract: There is provided a process for preparing caustic soda solutions from naturally occurring alkaline minerals comprising double salts of sodium carbonate and calcium carbonate. The process comprises heating said naturally occurring alkaline minerals to temperatures sufficient to dehydrate and partially decarbonate said alkaline minerals and provide an intermediate product of a mixture of sodium carbonate and calcium oxide. This intermediate then is contacted with water to effect causticization of the sodium carbonate and provide a recoverable phase comprising an aqueous solution of caustic soda.

Abstract: In the manufacture of particulated metal oxides by the vapor phase oxidation of volatile metal halides, hot gaseous effluent streams are produced which, after separation of the desired particulated metal oxide therefrom, contain residual amounts of the particulated metal oxide as well as unreacted, volatile metal halide and halogen gas. The method of this invention provides for the recovery of these materials, individually, through a succession of contacting and separating steps utilizing a recycle stream of previously recovered, unreacted, liquid metal halide. Utilization of the recycle stream of metal halide provides for both evaporative cooling of the hot gaseous effluent stream to permit recovery of the residual particulated metal oxide therein and scrubbing of the resulting off-gas to recover the unreacted volatile metal halide therein as a liquid and provide a gas phase containing the by-product halogen gas.

Abstract: A method of removing aqueously soluble salt by-products produced by the treatment of raw titanium dioxide particles to add a finish thereto. The finished titanium dioxide particles with the salt are subjected to demineralization with mixed bed ion exchange resins to produce finished titanium dioxide particles substantially free of salt and salt forms of ion exchange resins. The finished titanium dioxide particles are recovered and the salt forms of ion exchange resins are regenerated to produce recoverable salt and reusable resins.

Abstract: A process for the recovery of calcium chloride produced in the conversion of metal chloride by-products of chlorination to hydrous metal oxides. The hydrous metal oxides and other by-products of chlorination are insoluble in an aqueous solution of at least about 75 weight percent calcium chloride having a generally neutral pH and temperature between about 174 degrees centigrade and about 200 degrees centigrade. Calcium chloride also is readily recovered from the above solution.

Abstract: A process for the preparation of manganese sulfate solutions having reduced levels of potassium impurity comprising blending a reduced manganese ore, an added source of water soluble aluminum ions and an aqueous acid solution to form a digestion mixture, digesting said mixture, preferably in the presence of crystals of a complex potassium-aluminum salt to form a mixed reaction product containing a liquid phase of manganese sulfate solution and recovering the liquid phase of manganese sulfate solution from said mixed reaction product.

Abstract: Titanium tetrachloride is produced from titanium ore and reductant suspended in molten salt by the passage of chlorine therethrough. The titanium tetrachloride is scrubbed by passage through at least one scrubber of molten salt and oxidized to produce titanium oxide and chlorine. Chlorine is recaptured as a solute in cold titanium tetrachloride and then liberated and recycled.

Abstract: A process for separating inorganic substances involving their abstraction from a mixture with near-supercritical inorganic fluids. One or more inorganic substances are abstracted and then separatively recovered by retrograde condensations. The process particularly is applicable with mixtures obtained from the chlorination of metalliferous ores and may be conjoined to many ancillary metal abstraction processes such as volatilizations, distillations or electrolyses.

Abstract: A process of chlorinating titanium ore suspended with carbonaceous reductant in molten salt by passage of chlorine therethrough. Titanium tetrachloride produced is purified of by-product metal chlorides by their absorption in the salt as non-volatile double salts.

Abstract: A process for effecting deashing solvent recovery from insoluble coal products and preparing a slurry of the insoluble products. An elevated temperature and pressure stream comprising insoluble coal products and deashing solvent is admixed with a makeup liquid to dilute the stream. The diluted stream is reduced in pressure and introduced into a first treatment vessel containing sufficient slurry to provide a hydrostatic pressure to prevent boiling of the diluted stream upon entry therein. The solvent then is permitted to flash and cool the remainder of the slurry. A portion of the cooled slurry is recycled to provide the makeup liquid and a second portion is introduced into a second treatment vessel to permit diffusion of solvent infused into the insoluble coal products in the slurry. The slurry of insoluble coal products in the second vessel then is introduced into a thickener to concentrate the slurry and provide a feed suitable for a gasifier.

Abstract: A continuous process for recovering substantially pure aluminum chloride from chlorination products of aluminum ore. The chlorination products are contacted with a first selective solvent to dissolve a substantial portion of the aluminum chloride and some ferric chloride. The solvent is separated from the chlorides which then are treated to produce a ferric chloride-rich stream and an aluminum chloride-rich stream in which the aluminum chloride to ferric chloride ratio is higher than the ratio prior to solvent separation. The aluminum chloride-rich stream is contacted with a second solvent to dissolve any ferric chloride present and saturate the solution with aluminum chloride. Aluminum chloride in excess of that soluble in the second solvent separates as a substantially pure solid phase. The solution is separated from solid phase and recycled in process to recover additional aluminum chloride.

Abstract: In a process for the removal and pressure reduction of a high pressure, high temperature slurry from a process vessel, the slurry is mixed with a make-up liquid in a temperature treatment vessel to form a diluted slurry, which is passed through a cooling apparatus, and a recycle portion of the diluted slurry is recycled to the temperature treatment vessel. Another portion of the cooled diluted slurry solution is flashed to a preselected reduced pressure through a pressure reducing valve, and this portion is passed to a stripping vessel for concentrating and producing a slurry product. In operation, plural slurry gravity settling vessels may be connected to a single heat treatment vessel, thereby effectuating slurry pressure reduction across a single pressure reducing valve.

Abstract: An improved process for the production of synthetic rutile from ore containing titanium and iron, such as ilmenite ore, by a multi-step procedure employing controlled reduction, controlled oxidation and acid leaching. More specifically, the ilmenite ore first is reduced thermally such that substantially all of the iron (III) present has been converted to iron (II) and some metallic iron. The reduced ore then is oxidized with an oxidizing gas substantially free of elemental oxygen to convert the metallic iron to iron (II) without the substantial formation of iron (III). The oxidized ore then is leached to remove the iron (II) and calcined to produce synthetic rutile. The synthetic rutile so produced contains in excess of 92 percent titanium dioxide and less than 2 percent iron (III), by weight. Often, the synthetic rutile contains less than 1 percent total iron by weight.

Abstract: This invention relates to an improved heat exchanger gas outlet tube in a cyclone separator. The apparatus is adapted for use with highly corrosive halide-containing gas-solids suspensions at elevated temperatures.In accordance with this invention, a flanged, hollow nickel alloy gas outlet tube is provided with multiple inlets and outlets arranged circumferentially around a portion of the gas outlet tube. A hollow passage contained within said gas outlet tube is provided with a pair of partial longitudinal baffles positioned in such a manner that cooling air or other compatible cooling fluid may flow within the passage and be caused to flow longitudinally down the length of the tube, in one portion of the passage, before passing below the partial baffles and the flow back upwardly through the other portion of the passage.