Abstract: Finely divided, wet-ground, dispersant-free calcium carbonate filler or pigment compositions are disclosed in which the particles of calcium carbonate are distributed in particular amounts in a particular fashion--broadly stated: in fine particle size distribution. Such compositions are useful in aqueous slurry or dry form as opacifying fillers for paper.

Abstract: A precipitated calcite of substantially spherical morphology having an average spherical diameter of from 2 to 10 microns and a specific surface area of from 1 to 15 square meters per gram is prepared by introducing carbon dioxide gas into an aqueous slurry of calcium hydroxide containing dissolved polyphosphate in the amount of from 0.1 to 1.0 percent, calculated as grams of phosphorus per 100 grams of the calcite equivalent of the calcium hydroxide, the starting temperature of the carbonation being 15.degree. to 50.degree. C. The spherical calcite is particularly suitable for use in dull finish coated paper.

Abstract: Calcium carbonate single crystal, which can be optically used and industrialized, is produced by hydrothermal synthesis method in which the single crystal over species crystal is grown by using NaCl or KCl or LiCl aqueous solution under fixed temperature and pressure.

Abstract: An optically transmittant body of a ternary sulfide material such as calcium lanthanum sulfide is provided by concurrently precipitating from a nitrate solution of calcium and lanthanum, calcium carbonate and lanthanum carbonate. The precipitation reaction forms a homogeneous fine particle size starting powder of calcium carbonate and lanthanum carbonate powders. The starting powder is reacted with a sulfurizing agent such as hydrogen sulfide to convert such starting powder into a calcium lanthanum sulfide powder. The particle size of the homogeneous starting powder is sufficiently small to permit substantially complete and uniform conversion of such starting powder into the calcium lanthanum sulfide powder. The calcium lanthanum sulfide powder is then compacted into the desired form of the optically transmittant body and is subsequently sintered at an elevated temperature in an atmosphere of excess sulfur to increase the density of the material.

Abstract: Finely divided lime, at any degree of slaking, is introduced in a steady stream into an agitated reactor designed to produce pellets or aggregates. Concentrated acetic acid is simultaneously introduced in a steady stream at a rate equal to the chemical combining rate required to produce calcium magnesium acetate. Water content of the reaction stream is critical; the mol ratio of water, including water of neutralization, to the calcium magnesium acetate product must fall in the range 3.3-7.0 in order to form the desired pellets and to avoid sticking, caking, and dust emanation from the reactor. Product pellets are drawn off in a stream from the reactor and dried for use as a non-polluting roadway and walkway deicer. Traction agent is optionally incorporated into the deicer pellets by introducing a steady stream of traction agent to the reactor simultaneous with raw materials introduction. Magnesium-to-calcium ratios greater than one are achieved by blending dolime with magnesium-rich ore.

Abstract: A process for producing basic aluminum magnesium carbonate, Al.sub.2 Mg.sub.6 (OH).sub.14 (CO.sub.3).sub.2.4H.sub.2 O, by carbonating an aluminum hydroxide (Al(OH).sub.3) and magnesium hydroxide aqueous reaction mixture with carbon dioxide in the presence of at least 6 moles of a base selected from the group consisting of ammonia, mono, di or trialkylamines, pyridine or piperidine, per mole of Al.sub.2 O.sub.3 present. The product is useful as an antacid.

Abstract: The invention provides particulate calcium carbonate having incorporated therein from 0.1 to 10% by weight, based on the weight of calcium carbonate, of polymaleic acid or a water-soluble salt thereof.

Abstract: Crystalline, basic magnesium aluminum hydroxycarbonate of the formulaAl.sub.2 Mg.sub.6 (OH).sub.12 (CO.sub.3).sub.3.xH.sub.2 Owhere x is at least 4. A process for producing it comprises the conversion of aluminum hydroxide with basic magnesium carbonate and at least one compound selected from magnesium hydroxide and magnesium oxide. Stoichiometric quantities are employed with reference to the aluminum and the magnesium. The conversion takes place at temperatures from 50.degree. to 100.degree. C., and the resulting product is subsequently spray dried.

Abstract: An improved double alkali process is disclosed which is useful for the removal of sulfur dioxide from gas streams, especially waste gas streams derived from coal-fired plants which also contain entrained fine particles of ash which contain alkali, which process comprises leaching soluble alkali from said entrained fine particles to establish an aqueous alkali scrubbing solution, scrubbing the resulting gas stream with said scrubbing solution, which circulates between said leaching and scrubbing steps, followed by bleeding off a portion of the resulting scrubber effluent to a regeneration system wherein the alkali scrubbing solution is regenerated.

Abstract: A new basic aluminium magnesium carbonate of the formula Al.sub.2 Mg.sub.6 (OH).sub.14 (CO.sub.3).sub.2.4H.sub.2 O has been found to be useful in pharmaceutical formulations for the treatment of upper gastrointestinal tract disturbances associated with excess acid and pepsin secretion or biliary reflux.

Abstract: A heat storage system which is comprised of calcium chloride hexahydrate as the storage medium and a nucleating agent, said nucleating agent being a mixture of dolomite and calcium hydroxide.

Abstract: A process of making a calcium acetate-containing solution having a pH value at room temperature between about 7 and about 8 is provided comprising reacting acetic acid with a carbonate compound, adding calcined limestone, and optionally finishing off the acid-base reaction with an amount of an alkali metal hydroxide comprising from about 2% to about 5% of the total stoichiometric complement to the amount of acetic acid. Further process options which may be used in the preparation of deicing agents include adding coarse limestone to the above-prepared calcium acetate-containing solution in amounts up to 10% by weight and converting the solution into solid flakes. The calcium acetate salt product can be mixed with an inert solid material having good anti-slip properties.

Abstract: A process of reacting aqueous acetic acid and crushed raw limestone in such a way as to produce a mixture of calcium acetate, calcium acid-acetate, and unreacted raw limestone devoid of undesirable fine limestone. Such a product is useful in winter highway treatment, where the environmentally safe soluble acetates function to depress the freezing point of water, and the limestone acts as a roadway traction agent. When as much as 3 mols of acetic acid per mol of active calcium carbonate in limestone are used, all the limestone is consumed, with virtually 100% yield of calcium acid-acetate.

Abstract: A process of making a calcium acetate-containing solution having a pH value at room temperature between about 7 and about 8 is provided comprising reacting acetic acid with a carbonate compound, adding calcined limestone, and optionally finishing off the acid-base reaction with an amount of an alkali metal hydroxide comprising from about 2% to about 5% of the total stoichiometric complement to the amount of acetic acid. Further process options which may be used in the preparation of deicing agents include adding coarse limestone to the above-prepared calcium acetate-containing solution in amounts up to 10% by weight and converting the solution into solid flakes.

Abstract: Intimately mixed dry chemical formulations consisting of (1) a stable acid-acetate salt and (2) a chemical base for use as water-activated exothermic deicing agents, and/or as the dry chemical components of a warming device. The salt is optionally calcium monoacid acetate, sodium diacetate, or calcium magnesium monoacid acetate wherein up to 7 mol percent of the metal is magnesium. The chemical base is optionally calcium oxide or hydroxide, magnesium oxide or hydroxide, or calcined limestone. The relatively non-polluting formulations are pelletized or otherwise aggregated for application to roads, highways, walkways and parking lots as deicers.

Abstract: Strontium carbonate is prepared by the process of reacting strontium nitrate in an aqueous reaction medium with carbon dioxide to precipitate strontium carbonate product, the nitric acid byproduct that forms being neutralized by the introduction of lime to the reaction medium.

Abstract: A process for the manufacture of phosphoric acid from phosphate rock is provided. The phosphate rock is digested or acidulated with an acid solution containing oxalic acid to produce phosphoric acid and calcium oxalate. Useful by-products are also formed and include calcium carbonate and ammonium oxalate. More specifically, the process provides for the production of phosphoric acid, ammonium phosphate and useful by-products utilizing synthesis gas and air to produce oxalic acid and ammonia. The synthesized oxalic acid is utilized for phosphate rock digestion to produce phosphoric acid, which can be reacted with ammonia to produce ammonium phosphate. Calcium oxalate from phosphate rock digestion is utilized to produce calcium carbonate, ammonium oxalate and oxamide.

Abstract: A process of making different grades of calcium magnesium acetate deicing agents, having substantially uniform but different calcium-to-magnesium mole ratios, from limestone having varying proportions of calcium carbonate and magnesium carbonate, is provided wherein limestone containing calcium and magnesium carbonates is finely divided, mixed with water to form an aqueous suspension of limestone, vigorously agitated and reacted with excess acetic acid. The reaction is completed by adding to the reaction batch about 30% of the molar equivalent of calcined finely divided limestone base to produce a calcium magnesium acetate salt solution having a calcium-to-magnesium mole ratio much greater than one. The insolubles from this first reaction are removed, calcined and reacted with acetic acid in a second reaction to produce a calcium magnesium acetate salt solution having a calcium-to-magnesium mole ratio substantially equal to one.

Abstract: A process of making a calcium acetate-containing solution having a pH value at room temperature between about 7 and about 8 is provided comprising reacting acetic acid with a carbonate compound, adding calcined limestone, and optionally finishing off the acid-base reaction with an amount of an alkali metal hydroxide comprising from about 2% to about 5% of the total stoichiometric complement to the amount of acetic acid. Further process options which may be used in the preparation of deicing agents include adding coarse limestone to the above-prepared calcium acetate-containing solution in amounts up to 10% by weight and converting the solution into solid flakes.

Abstract: A method for leaching magnesium from a magnesium hydroxide-containing composition, especially a mineral, which comprises contacting said composition with an aqueous solution of an ammonium salt whose corresponding magnesium salt is soluble in said aqueous solution to thereby produce said soluble magnesium salt; separating said aqueous solution from said composition; and transforming the magnesium of said soluble magnesium salt into an insoluble magnesium compound. The method is particularly useful for leaching magnesium from brucite-containing chrysotile asbestos fibers, to yield both a magnesium compound and brucite-free, dispersed chrysotile fibers.

Abstract: A synthetic CO.sub.2 acceptor consisting essentially of at least one compound selected from the group consisting of calcium oxide and calcium carbonate supported in a refractory carrier matrix, the carrier having the general formula Ca.sub.5 (SiO.sub.4).sub.2 CO.sub.3. A method for producing the synthetic CO.sub.2 acceptor is also disclosed.

Abstract: Mineral filler such as calcium carbonate, having at most 15% by weight of particles which are smaller than 0.2 .mu.m with a corresponding spherical diameter, method of preparation, and use thereof are provided.

Abstract: The present invention relates to a non-mechanical method of converting coarsely ground limestone to a very fine powder. A slurry of ground calcium carbonate or limestone is contacted with carbon dioxide gas at high pressure to convert the solids in the slurry to an unstable form. The carbon dioxide pressure is then instantaneously released to form a slurry of activated calcium carbonate particles substantially reduced in size. This activated calcium carbonate slurry may be used to scrub flue gases.

Abstract: A chemical, electro-chemical process for recovering meta values from a zinc- or lead-containing material comprises:in a solubilization stage, oxidizing the zinc- or lead-containing material by treating said material with a ferric chloride leach solution;when solubilized lead is present, separating it from the pregnant liquor forming an essentially lead free solution;dividing this essentially lead free solution into two portions;passing one portion of the essentially lead free solution into the anolyte compartment of a Zn.degree. producing electrolysis stage for use as the ferrous ion-containing anolyte thereof;separating iron from the second portion of the essentially lead free solution, forming an essentially iron free solution;passing the essentially iron free solution into the catholyte compartment of said Zn.degree. producing electrolysis stage for use as the catholyte thereof;conducting electrolysis in said Zn.degree.

Abstract: The binder demand of particulate inorganic filler is reduced without essentially altering the filler's surface area by subjecting the filler alone to intense rotary impact agitation at a peripheral speed of from about 20 to 60 meters per second. Compositions comprising a binder together with a filler prepared by this method include those in which the binder comprises alkyd resin, especially an unsaturated polyester resin, epoxy resin or linseed oil and the filler comprises ground limestone, talc or hydrated alumina.

Abstract: A stable, pumpable suspension of a calcium carbonate mineral is prepared by a method which includes the step of removing abrasive particles from a deflocculated, concentrated aqueous suspension of the calcium carbonate mineral by centrifuging the suspension at a solids content of at least 65% by weight under conditions such that the quantity of particles in said suspension having an equivalent spherical diameter larger than 10 .mu.m is reduced.

Abstract: The invention provides calcium carbonate particles comprising a core and projections formed thereon, and process for preparing same. The calcium carbonates of this invention are useful as fillers and pigments for rubbers, plastics, papers, etc. because of their peculiar configuration and unique properties.

Abstract: Process for the preparation of an aqueous suspension containing at least 65% by weight of calcium carbonate, in which process calcium carbonate is crystallized in a dilute aqueous medium, a wet concentrate of calcium carbonate is separated from the resulting dilute aqueous suspension of calcium carbonate and the said calcium carbonate concentrate is fluidized and homogenized in the presence of a dispersing agent. The calcium carbonate is crystallized in the presence of a water-soluble polyelectrolyte and the calcium carbonate concentrate is separated from the dilute suspension of calcium carbonate by essentially mechanical separating means.

Abstract: Method for improving the brightness of limestone utilizing a flocculating agent and a bleaching agent where the pH of the slurry is between about 7 and 9.

Abstract: Stabilized amorphous calcium carbonate which is useful as a carbonate factor in effervescent compositions. Process for preparing stabilized amorphous calcium carbonate and compositions containing stabilized amorphous calcium carbonate.

Abstract: The recovery of a magnesium carbonate of high purity from an aqueous slurry comprising a mixture of calcium carbonate and hydrated magnesium carbonate is disclosed. Carbon dioxide is introduced into the slurry while the temperature thereof is maintained not higher than about 40.degree. C. to produce an appreciable concentration of magnesium cations in the water of the slurry. Introduction of carbon dioxide is discontinued while most of the calcium is present as the carbonate. Solids are then separated from the aqueous solution of magnesium cations which is produced. Also disclosed is the removal, e.g., by means of a vacuum pump, of carbon dioxide from the aqueous solution of magnesium cations to precipitate magnesium carbonate and the separation of precipitated magnesium carbonate from the aqueous phase.

Abstract: An improved calcium carbonate filler in the form of a powder having a particle size distribution range and other identifiable physical characteristics produces unexpected results as a filler in resin molding compounds.

Abstract: Surface-treated calcium carbonate powders of this invention are easy to handle and highly dispersible in water, give slurries of high concentration and are useful as pigments and various other applications.

Abstract: Chain structured corpuscular calcium carbonate is produced by a carbonation of calcium hydroxide suspended in water in the presence of a chelating agent and a water soluble metal salt.

Abstract: A method of producing finely-divided phosphor grade calcium carbonate having a calcite crystalline structure and a very low sodium content. The calcium carbonate is produced from calcium chloride having a high sodium impurity content, such as calcium chloride which is a by-product of the Solvay process for producing soda ash.

Abstract: A process for the extraction of oil from oats is disclosed. The process comprises extracting oil from comminuted oats with 2-propanol and separating the resultant 2-propanol solution from the de-oiled oats. Oat oil is recoverable from the 2-propanol solution. The 2-propanol may be in the form of an azeotropic mixture of 2-propanol and water. In a preferred embodiment the 2-propanol contains a minor amount e.g. 0.1- 1.0%, of hydrogen peroxide. The process is capable of producing a clear, lightly colored oil from oats. The oil is believed useful as a vegetable oil.

Abstract: A malleable or press-forgeable ingot of barium fluoride, for use as an optical body, may be grown from an ultra-pure precipitate of barium fluoride which contains less than 10 parts per million (ppm) of strontium or calcium. A process is disclosed for crystallizing barium nitrate crystals in the presence of nitric acid, reacting barium nitrate with ammonium carbonate to form barium carbonate, recovering barium carbonate crystals, suspending the barium carbonate crystals in water and precipitating barium fluoride with hydrofluoric acid. The barium fluoride crystals are recovered, dried and then calcined in the presence of ammonium fluoride or bifluoride. Barium fluoride (BaF.sub.2) crystals obtained by the process of this invention contain less than 10 ppm of each strontium and calcium.Crystals of an alkaline earth metal fluoride which have been calcined in the presence of a fluoride of ammonium are unexpectedly densified, and are particularly suited for melt-growth of an ingot in a known manner.

Abstract: Limestone-expanding clay granules produced by charging a pulverizer and/or a mixer, with a raw material, which is high in calcium and/or magnesium, and an expanding clay binder, the expanding clay binder comprising from 1% and not more than 10% of the total charge. A portion of the material from the pulverizer is recycled back through the pulverizer, the amount recycled being determined by, among other things, the fineness of the raw material in the desired finished product. The remainder of the material from the pulverizer is caused to pass through a granulator, a dryer-cooler, and a finished product screen means. Fines from the finished product screen means are recycled directly to the pulverizer. Oversize material from the finished product screen is recycled to the pulverizer or to separate crusher and then back over the finished product screen means, where fines are removed and sent back to the pulverizer.

Abstract: This invention relates to a process for the treatment of the reaction mass produced during the joint elimination of barium-containing nitrite-/nitrate-bearing carburizing salt wastes and cyanide-/cyanate-bearing wastes by ignition of the dry mixture at elevated temperatures, comprising suspending the reaction mass in water and eitherA. neutralizing the alkaline suspension obtained with concentrated nitric acid to a pH value of 6, the feed velocity of the acid and conditions of agitation being so selected that the pH value of the suspension will at no time fall below pH 6, and separating the barium carbonate,OrB. freeing the alkaline suspension obtained from barium carbonate, and neutralizing the filtrate with concentrated nitric acid to a pH value of 7.2, the feed velocity of the acid and conditions of agitation being so selected that the pH value of the suspension will at no time fall below pH 7.

Abstract: This invention relates to a process for the treatment of the reaction mass produced during the joint elimination of barium-containing nitrite-/nitrate-bearing carburizing salt wastes and cyanide-/cyanate-bearing wastes by ignition of the dry mixture at elevated temperatures, comprising suspending the reaction mass in water and either (a) adding a water-soluble barium salt to the aqueous suspension in equimolar quantities, based upon carbonate ions, and separating precipitated barium carbonate, or (b) freeing the alkaline suspension from barium carbonate by filtration, reacting the filtrate with a water-soluble calcium salt, and separating precipitated calcium carbonate, concentrating the clear solutions obtained according to (a) or (b) to a water content of 10-20% by weight, separating precipitated sodium chloride, and evaporating the residual solution to dryness.

Abstract: Finely divided lime, at any degree of slaking, is introduced in a steady stream into an agitated reactor designed to produce pellets or aggregates. Concentrated acetic acid is simultaneously introduced in a steady stream at a rate equal to the chemical combining rate required to produce calcium magesium acetate. Water content of the reaction stream is critical; the mol ratio of water, including water of neutralization, to the calcium magnesium acetate product must fall in the range 3.3-7.0 in order to form the desired pellets and to avoid sticking, caking, and dust emanation from the reactor. Product pellets are drawn off in a stream from the reactor and dried for use as a non-polluting roadway and walkway deicer. Traction agent is optionally incorporated into the deicer pellets by introducing a steady stream of traction agent to the reactor simultaneous with raw materials introduction. Magnesium-to-calcium ratios greater than one are achieved by blending dolime with magnesium-rich ore.