Abstract: A bonded abrasive article includes elongate shaped abrasive particles. The elongate shaped abrasive particles comprise an elongate shaped ceramic body having opposed first and second ends joined to each other by at least two longitudinal sidewalls. At least one of the at least two longitudinal sidewalls is concave along its length. At least one of the first and second ends is a fractured surface.

Abstract: A process is disclosed for recovering lithium from a lithium-containing silicate mineral. The process comprises mixing the silicate mineral with nitric acid. The process also comprises subjecting the mixture to a leaching process having conditions such that lithium values in the silicate mineral are leached into an aqueous phase as lithium nitrate. The leaching process conditions may be controlled such that non-lithium values in the silicate mineral tend not to be leached into the aqueous phase.

Abstract: As population density increases, the transportation of hazardous chemicals, including acids and disinfectants, lead to an increased incidence of spills while the consequences of spills become more serious. While solutions of halide acids, hypohalites and halites are safer disinfectants for transportation, handling, storage and use than traditional gaseous chlorine, the manufacturing cost of these disinfectants has here-to-fore limited their use. Economical processes are presented for the manufacture of O2, halogen oxides, halide acids, hypohalites, and halates; as well as polynucleate metal compounds, metal hydroxides and calcium sulfate hydrate (gypsum). The instant invention presents methods and processes that incorporate the use of sulfur. This is while environmental regulators, such as the US EPA, require an increased removal of sulfur from hydrocarbon fuels, thereby creating an abundance of sulfur, such that the refining industry is in need of a way to dispose of said abundance of sulfur.

Abstract: Disclosed is a process for removing metals from waste, particularly electronic waste (or “e-waste”). The process generally includes the steps of dissolving at least some of the metals from the waste with nitric acid reagent and then causing at least some of the metals to precipitate as metal oxides and/or metal nitrates. NOx gases produced as by-product by the nitric acid dissolution of metallic components in the electronic waste are reused, in particular for generating permanganate when one of the metallic components comprises manganese.

Abstract: The invention relates to a process for the purification of aqueous solutions polluted by nitrate ions. This process is characterised in that it consists in precipitating hydrated double or mixed calcium nitroaluminates, such as, in particular, hydrated calcium mononitroaluminate, by adding at least one agent supplying the element aluminium and at least one agent supplying the element calcium to the solutions to be treated, the overall mole ratio of the element aluminium to nitrate, Al/NO3, being superior to 1 and the overall mole ratio of calcium to nitrate, Ca/NO3, being superior to 2, and in that the precipitation reaction is performed with stirring and at a basic pH, preferably above 10.5.The process according to the invention is intende, in particular, to the treatment of polluted waters such as municipal waste water and factory effluents and to the treatment of liquid manure.

Abstract: A method for recovering gallium, which comprises a capturing step of contacting an aqueous solution containing gallium to a chelating agent containing a water-insoluble substituted quinolinol as the active ingredient, to let the chelating agent capture gallium, and an eluting step of contacting an eluting solution composed of an aqueous solution of an acid or strong base containing said substituted quinolinol, to the chelating agent from the capturing step, to elute gallium therefrom.

Abstract: Aluminum nitrate solutions are subjected to hydrolysis at elevated temperature and pressure, with the pressure being kept relatively low by continual bleeding of reactant gases from the reaction vessel. The resultant product is a noncrystalline alumina that may be readily converted to crystalline alumina by roasting.In addition, the discharged reactant gases are employed for leaching of clay to provide aluminum nitrate feed solution.

Abstract: The invention described herein relates to a method for improving the acid leachability of aluminum and other metal values found in fly ash which comprises sintering the fly ash, prior to acid leaching, with a calcium sulfate-containing composition at a temperature at which the calcium sulfate is retained in said composition during sintering and for a time sufficient to quantitatively convert the aluminum in said fly ash into an acid-leachable form.

Abstract: Alumina values are extracted from clay by the steps of pelletizing into spherical particles, calcining the pellets in a fluidized bed reactor, extracting the clay in about 30-40% nitric acid, purifying the basic aluminum nitrate produced, crystallizing aluminum nitrate nonahydrate, decomposing the nonahydrate in at least three steps, calcining the produced alumina and reconstituting the NO.sub.x gases to nitric acid.

Abstract: Alumina monohydrate is produced by leaching calcined clay and subjecting the leach liquor to pressure hydrolysis wherein the vapor and heat resulting from the pressure hydrolysis are directly utilized for leaching of the calcined clay. The aluminum monohydrate may be roasted to yield alumina.

Abstract: A method is provided for recovering metal compounds and metals from ores, concentrates, alloys and other metal containing materials. The material containing said metals is leached in an aqueous solution of nitric acid at atmospheric pressure and temperatures which may vary from ambient to the atmospheric boiling point. An inorganic salt is admixed or formed in the solution to raise the atmospheric boiling point of said solution. The solution is heated to evaporate the water and to increase the concentration of the salt. The atmospheric boiling point of the solution increases with an increase in the salt concentration and causes an evolution of nitric acid or nitrogen containing gas and the sequential precipitation of metal compounds as the boiling point of the solution increases. The solution is filtered after each sequential precipitation to recover the metal compound or mixture of metal compounds which have precipitated as aforesaid.