Abstract: Disclosed herein are kaolin compositions, such as beneficiated fine sedimentary kaolin compositions. The beneficiated fine sedimentary kaolins may be obtained from the upper bed of the Rio Capim Kaolin deposit. The compositions may have at least one property chosen from a low iron content and low Hinckley crystallinity index, such as Fe2O3 in an amount less than about 0.8% by weight relative to the total weight of the solids content and wherein the Hinckley crystallinity index of the kaolin is less than about 0.5. Also disclosed are products obtained therefrom, such as paint and paper coating compositions.

Abstract: This invention is related to processing kaolin by controlled flow cavitation (CFC), and in particular, this invention is directed to kaolin ozonation and/or bleaching processing through application of CFC.

Abstract: Methods for treating lignocellulosic material or pigment with a reductive bleaching solution generally include washing the lignocellulosic material or pigment with a reducing agent of magnesium dithionite. The method includes at least one reductive stage and at least one peroxide stage. Also disclosed are methods for preparing dithionite solution wherein magnesium bisulfite is reduced with borohydride solution to obtain dithionite. Bleached lignocellulosic material or pigment obtained with the treatment methods are also disclosed.

Abstract: The present invention relates to a kaolin composition having improved physical properties, for example, for use in the production of paper products. The composition can comprise kaolin having a shape factor of at least about 20. The kaolin can have a particle size distribution such that at least about 94% by weight of the kaolin can have an esd of less than about 2 ?m and/or at least about 80% by weight of the kaolin can have an esd of less than 1 ?m. The amount of the kaolin having an esd of less than about 0.25 ?m can range from about 25% to about 60% by weight. The Hercules viscosity of the kaolin product is less than 4000 rpm at 18 dynes at 63% solids and less than 1500 rpm at 18 dynes at 69% solids when measured using the “A” bob. The present invention also relates to an improved method for making the kaolin product from sedimentary kaolin.

Abstract: Disclosed are methods for making ultrafine silica particles in a plasma system, apparatus for making ultrafine silica particles, and coating compositions comprising ultrafine silica particles made by such methods and/or apparatus.

Abstract: Aqueous dispersion which comprises hydrophobized silicon dioxide powder with a content of between 5 and 50 wt. % and which comprises at least one compound of the general formula R & supl; —COO—(CH2-CH(Ph)—O)a-(CnH2n-xR2x-O)b-R3 (I). It is prepared by dispersing the hydrophobic silicon dioxide powder, dispersing agent and optionally pH-regulating substances and further additives in an aqueous medium. It can be employed as an additive to waterborne fillers in the automobile industry, as a coating constituent in can and coil coating processes, as an additive in water-based UV-curable formulations e.g. for wood preservation and as a constituent of protective lacquer films.

Abstract: Disclosed are methods of processing kaolin to produce ultrafine hydrous kaolin. The methods involve processing gray crude kaolin by subjecting the kaolin crude to flotation and then centrifuging the kaolin to provide a fine stream that is subject to refinement. Also disclosed are systems for the automated processing of gray crude kaolin to produce the ultrafine hydrous kaolin and paint compositions that contain the ultrafine hydrous kaolin.

Abstract: The present invention provides high brightness kaolins exhibiting a Brightness (GE) of at least about 90.0. The hydrous kaolin pigments of the present invention may also have, inter alia, a steepness index (d30/d70×100) of at least about 39 and/or a titania concentration less than or equal to about 0.40% by weight of the pigment on a dry basis. (062) The hydrous kaolin pigment is produced by a process comprising: a) forming an aqueous suspension of a hydrous kaolin clay; b) forming a primary product by subjecting the suspension to classification or a combination of classification and griding; c), separating the kaolin from impurities by selective flocculation; and d) defining the separated kaolin. (063) The hydrous kaolins of the present invention allow coated papers to be produced at high brightness while maintaining acidic conditions on a paper machine. The invention pigmets exhibit brightness levels unexpectedly higher, e.g., about 2 to about 2.

Abstract: The present invention provides an improved method of beneficiating and dewatering kaolin clays. The product of the improved process is a brightened, dewatered kaolin, suitable for use in pigments and paper coating compositions. The improved beneficiation process provides refined kaolin for pigments and other purposes of the same or better quality as prior art processes, but with the use of fewer steps and materials, at significant cost and environmental savings.

Abstract: This invention provides improved kaolin clay slurries by processes for addition of stabilized chlorine dioxide which oxidizes organic impurities, including living organisms and organic debris, to kaolin clays and bleaching agents used in the paper-making industry.

Abstract: In a process for preparing a white pigment mixture suitable for coating paper wherein a cationically bulked kaolin clay pigment is dispersed in water in the presence of an anionic dispersant and mixed with a calcium carbonate pigment, the improvement which comprises using an epichlorohydrin amine complex to bulk said kaolin, and employing as the dispersant the combination of at least 0.2% based on the dry weight of said cationically bulked kaolin of a condensed naphthalene sulfonate complex having a molecular weight of 2000 to 10,000 and a sodium polyacrylate salt having a molecular weight of 2000 to 5000, said dispersant being free from lignosulfonate.

Abstract: The present invention provides kaolin clay pigments having at least the following characteristics: Brightness (GE): at least about 89.0; Shape Factor: at least about 30; Brookfield viscosity, measured at 20 rpm and at less than or equal to about 65% solids: about 100 to about 700 centipoise; and Hercules viscosity, measured at 18 dynes and at less than or equal to about 65% solids: about 200 rpm to about 1000 rpm. Preferred kaolin sources include Brazilian kaolins, especially Rio Capim kaolins. The kaolin pigments of the present invention possess a combination of optical and physical properties, such as brightness, printability, and transfer efficiency, not previously seen in existing commercial products. They are useful, e.g., in paper filler and coating compositions, ink compositions, and printing applications, especially rotogravure printing.

Abstract: The present invention provides a lightweight clay which can be easily molded into a given shape, exhibits proper lightweight characteristics and storing characteristics, and can be manufactured at a low cost, and a manufacturing method thereof. In such a lightweight clay and the manufacturing method thereof, an average particle size of the organic hollow micro spheres is set to a value which falls within a range of 15 to 150 &mgr;m and, an addition quantity of the organic hollow micro spheres is set to a value which falls within a range of 0.1 to 6 weight % with respect to a total quantity of the lightweight clay, and whiteness degree (WL) measured in accordance with JIS L 0803 is set to not less than 50.

Abstract: A pigment product suitable for use in a coating composition to provide a gloss coating on paper, the pigment product comprising a processed particulate kaolin produced from a naturally platy kaolin clay having a particle size distribution such that about 50% to 60% by weight of the particles have an esd less than 2 &mgr;m and less than 25% by weight of the particles have an esd less than 0.25 &mgr;m and a shape factor of at least 15. This platy clay can be blended with b-fraction clay component. In processing, the crude kaolin is ground to a shape factor greater than 50 to produce even greater “platy” clay. The pigment product has a particle size distribution such that at least 80% by weight of the particles have an esd less than 2 &mgr;m and greater than 12% and less than 35% by weight of the particles have an esd less than 0.25 &mgr;m and whose surface area is greater than 12 m2/g when measured by the BET method.

Abstract: A method for the treatment of a kaolin clay crude to separate by selective flocculation impurity particles contained in the crude from finely divided kaolinite particle contained in the crude, comprising: (a) forming said crude into a dispersed aqueous slurry b adding water and at least one dispersant to said crude; (b) conditioning said dispersed aqueous slurry by adding conditioning chemical thereto, the conditioning chemical providing addition of monovalent cations to the slurry without adding multivalent cations thereto; (c) selectively flocculating said conditioned slurry by adding to said conditioned slurry a composition comprising (i) a high molecular weight component comprising an organic anionic polymer having a molecular weight of at least 1 million; and (ii) a low molecular weight component comprising an inorganic anionic polyphosphate; said composition causing impurity particles in said slurry to flocculate and settle as a dense lower layer and kaolinite particles in said slurry to be defloccul

Abstract: The present invention provides an activated clay for refining aromatic hydrocarbons such as BTX (benzene, toluene, xylene), etc., satisfying the requirements of both excellent life and excellent side-reaction-preventing property. The activated clay for treating aromatic hydrocarbons is obtained by treating dioctahedral smectite clay minerals with an acid so as to possess a BET specific surface area of not smaller than 250 m.sup.2 /g and to contain iron in an amount of not smaller than 2.5% by weight calculated as Fe.sub.2 O.sub.3.

Abstract: A process for making a bleaching clay composition useful for purification of oil is disclosed. The process involves controlled acidification of a palygorskite and smectite clay mineral with sulfuric acid. The clay mineral starting material exhibits, in an aqueous slurry, an electrical conductivity of at least about 50 microSiemens per centimeter.

Abstract: A method of enhancing the brightness and increasing the yield of a kaolin clay by optimizing the removal of the titania and mica impurities in the clay and the amount of clay remaining in the slurry is disclosed. The method is a selective flocculation process wherein the clay is blunged, dispersed, and conditioned before flocculation. In the flocculation step, a high molecular weight anionic polymer and a low molecular weight anionic polymer, such as sodium polyacrylate, are added to the slurry after the conditioning process, whereby the titania-mica enriched flocs are separated from the suspension which is enriched with kaolin. This final kaolin product has titania levels ranging from 0.1% to 0.5%, a reduced mica level, a high usable product yield, and a brightness greater than 89.5 and at least 91.5.

Abstract: This invention pertains to the use of a combination of polyvalent cations, clay dispersant and high molecular weight anionic polymer to preferentially remove colloidal fines (slimes) from a kaolin slurry, leaving the remainder of the kaolin in the slurry in the form of a coherent gelatinous mass.

Abstract: High performance acid activated clays suitable for bleaching oil are produced by contacting an intercalating clay mineral with a strong acid in a polar organic liquid.

Abstract: The present invention relates to a mineral eluting material for drinking water with granite as raw material and manufacturing method thereof and a structural body of mineral eluting material. The mineral eluting material includes granite crushed to sizes of 0.075.about.0.145 mm, submerged in 3.about.10% glucose solution for 24 hours, baked at 380.degree..about.400.degree. C. for 12.about.24 hours, and cooled at room temperature in a tightly sealed vessel. The structural body according to the present invention is manufactured by piling up granular granite and silver activated charcoal in 2-10 layers respectively and alternately in a cylindrical column. Water having passed the structural body according to the present invention comprising granular granite contains no impurities and abounds in minerals.

Abstract: Kaolin clay materials containing discoloring impurities can be beneficiated by microwave irradiation in the presence of water and a polyprotic acid component to produce a beneficiated kaolin clay material having improved color and brightness.

Abstract: A process for making a bleaching clay composition useful for purification of oil is disclosed. The process of involves controlled acidification of a palygorskite--smectite clay mineral with sulfuric acid.

Abstract: An improved method for improving the brightness of clay of the type that is capable of being bleached by an oxidative reagent, such as Georgia gray kaolin. Such clay, in the form of a dispersed slurry, is treated with a combination of an inorganic condensed phosphate, sodium hypochlorite and ozone, preferably including separate treatment steps of magnetic purification and reductive bleaching. Suitable phosphates include sodium hexametaphosphate, sodium tripolyphosphate and tetrasodium pyrophosphate. The hypochlorite is added shortly before ozonation, and the phosphate is added before, simultaneously with, or after the hypochlorite.

Abstract: A process for improving the rheological properties of an aqueous suspension of a particulate inorganic material which comprises the steps of: (a) forming an aqueous suspension of the particulate inorganic material and an effective amount of an anionic polyelectrolyte dispersing agent; (b) diluting the suspension formed in step (a) with water while maintaining the particulate in the dispersed state of step (a) to give a solids concentration of not less than 20% by weight of the particulate inorganic material; and (c) reconcentrating the diluted suspension formed in step (b) to give a solids concentration of at least 50% by weight of the particulate inorganic material.

Abstract: A method for beneficiating a low brightness fine particle size discolored kaolin crude to produce a high brightness coating clay. By combining the two beneficiating techniques of selective flocculation and ozonation, a synergistic phenomena occurs and a clay product of superior brightness and whiteness can be obtained from fine discolored clays that cannot be achieved by beneficiation with either process singularly. By passing the flocced clay through ozonation, the flocculant polymer left in the clay can be completely destroyed.

Abstract: A rotating cylindrical quartz glass tube is partitioned into at least 3 chambers comprising a pre-heating chamber, a reaction chamber, and a gas desorption chamber. The process comprises pre-heating the starting quartz powder by continuously supplying it into the pre-heating chamber, refining the powder by transferring it into the reaction chamber in which the powder is brought into contact with a chlorine-containing gas atmosphere, and transferring the powder into the gas desorption chamber; the chambers may be partitioned using a sectioning plate having an opening. Alkali metal elements such as sodium and potassium, as well as transition metal elements such as iron, copper, chromium, and nickel are removed from a powder of naturally occurring quartz. The process also removes alkaline earth metal elements such as magnesium and calcium. Furthermore, it is of high productivity because it can be operated continuously to yield high purity quartz powder at a low cost.

Abstract: A selective flocculation process that uses a mixture of dispersants including soda ash to disperse a slimed ore pulp prior to conditioning with a fatty acid, salt and then a polymeric flocculating agent.

Abstract: A process for preparing a high brightness, low abrasion calcined kaolin. A cretaceous crude is wet beneficiated by subjecting same as an aqueous slurry to degritting, classification, magnetic separation, and scrub grinding. The slurry from the foregoing is diluted to less than 15% solids and subjected while well dispersed to a separation in a centrifuge to yield an underflow and an overflow fine fraction having less than 5% solids and a P.S.D. such that at least 85% by weight are of <0.5 .mu.m E.S.D. and at least 30% by weight are of <0.25 .mu.m E.S.D. The overflow fine fraction slurry of dispersed kaolin is subjected to a partial filtration by passing same in cross flow relation to a microporous membrane through which substantially none of the suspended kaolin particles pass, to raise the solids content of the said slurry to at least 20%.

Abstract: A method which enables economical and highly effective preparation of refined kaolin clay products having preselected particle size distributions and brightnesses, by means of separate, efficient and economical processing of at least two crude components. A fine particle size kaolin crude having a PSD such that at least 85% by weight of the particles are of less than 2 micrometers ESD is wet beneficiated to provide a first product component having a PSD of at least 95% by weight less than 2 micrometers and a brightness of at least 89 on the G.E. scale. This wet beneficiation is conducted without use of a froth flotation step. A coarse particle size kaolin crude having a PSD such that less than 85% by weight of particles are of less than 2 micrometers ESD, is separately wet beneficiated to produce a second product component having a PSD of no more than 85% by weight less than 2 micrometers and a brightness of at least 89 on the G.E. scale.

Abstract: A method for brightening kaolin contaminated with organic matter by decarboxylation treatment of an aqueous kaolin slurry. The decarboxylation is carried out by contacting the clay slurry with selected oxidizing agent in a pressurized reaction vessel at a temperature of 175.degree.-500.degree. C. without dehydroxylation (calcination) of the kaolin. Oxidizing agents include oxygen, ozone, hydrogen peroxide, and hypochlorite.

Abstract: A process for reacting metallic iron with sulfur dioxide (SO.sub.2) gas in the presence of water and bleachable matter, especially iron-contaminated kaolin clay, whereby the kaolin or the like is bleached in situ and the viscosity of the kaolin is less than it would be if bleached in a conventional manner.

Abstract: A process for increasing the brightness of Minnesota kaolin clay containing chlorite and siderite mineral impurities comprising treating the clay with a strong mineral acid preferably in combination with magnetic separation.

Abstract: A method for producing calcined kaolin pigments of high opacifying properties and low abrasion. A kaolin crude is selected having a G.E. brightness in the range of 70 to 80, a titania content of 2.0 to 3.0% by weight, less than 2% iron expressed as Fe.sub.2 O.sub.3, and a particle size distribution such that at least 88% by weight of the particles of said crude are of less than 2 .mu.m E.S.D.. The crude is blunged with water, and the resultant slurry degritted to form an aqueous slurry having at least 65% by weight solids. The slurry is centrifuged and a fraction recovered having over 65% solids, and in which at least 92% by weight of the particles are of less than 2 .mu.m. The recovered fraction is dried to less than 1% moisture, and pulverized to break up agglomerates. The pulverized fraction is then calcined by heating same to 1450.degree. to 1600.degree. F. after which the calcined kaolin is milled to yield a product having a G.E. brightness of 79 to 81 and an Einleiner abrasion of not mere than 2.

Abstract: An improved method for improving the brightness of clay of the type that is capable of being bleached by an oxidative reagent such as Georgia gray kaolin. Such clay, in the form of a dispersed slurry, is treated with a combination of sodium silicate, sodium hypochlorite and ozone, most preferably followed by magnetic purification and a reduction bleach. Sodium hypochlorite is added shortly before ozonation.

Abstract: The present invention relates to a process for selectively purifying ceramic materials for glass, paper and electronics use contaminated with iron compounds, the process using ascorbic acid or its derivatives as the iron reducing agent.

Abstract: A process for producing a high solids aqueous slurry of a beneficiated kaolin. An impure crude kaolin clay is initially subjected to wet processing including a size classification step, to recover a beneficiated fine particle size kaolin fraction which is formed into a dilute aqueous slurry of deflocculated kaolin particles. The dilute slurry is filtered by flowing it generally parallel to and in contact with the surface of a microporous barrier while maintaining a pressure drop across the barrier in a direction transverse to the slurry flow. A gel permeation layer is thereby formed of kaolin overlying the surface of the microporous barrier. The gel permeation layer and underlaying surface are substantially impervious to the passage of clay solids while being pervious to the passage of water molecules, ions and dissolved salts; whereby water molecules, ions and dissolved salts are caused to pass through the barrier, thereby increasing the concentration of the solids in the kaolin slurry.

Abstract: A chemical process is described for removing ferric iron present in submarginal quantities in concentrates of kaolin, quartz, titanium minerals, ceramic minerals for glass, paper and electronics use and other materials of industrial interest by which ferric iron is reduced to ferrous iron using acid solutions, possibly in the presence of low concentrations of sugars containing 5 or more carbon atoms.

Abstract: A process for reacting metallic iron with sulfur dioxide (SO.sub.2) gas in the presence of water and bleachable matter, especially iron-contaminated kaolin clay, whereby the kaolin or the like is bleached in situ.

Abstract: A process is disclosed for producing high brightness kaolin from ore containing silica, other types of clays, minerals such as ilmenite micas, feldspars and various metal silicates as well as organic matter. The process consists of sizing, a double floatation step, magnetic separation, leaching and oxidative brightening steps. This is a novel combination of conventional unit operations and in particular the use of a double floatation step to remove quartz and various trace minerals that interfere with achieving high optical brightness for kaolin.

Abstract: A method for producing a low abrasion calcined kaolin pigment which comprises forming an aqueous pulp of crude kaolin dispersing the pulp by adding thereto sufficient water-soluble organic cationic dispersant to impart a positive zeta potential to said particles and, preferably, an acidic pH to said pulp, removing coarse particles from said dispersed pulp and fractionating the dispersed pulp to separate a fine particle size fraction of mineral particles from coarser particles. The fine particle size fraction is dried, pulverized, calcined and repulverized.

Abstract: A method for forming a hydrothermally aggregated kaolin clay pigment, comprising preparing an aqueous slurry of particulate kaolin clay and sodium aluminate, having a total solids concentration of from about 2 to 25% by weight, the weight ratio between kaolin and aluminate being greater than 1; and hydrothermally treating the slurry in a closed system to form aggregates of adherent kaolin platelets.

Abstract: A process is provided for purifying finely divided minerals contacting organic material sufficiently to make the minerals useful for coating a filling paper or for use as catalysts, catalyst supports or the like. The process comprises concomitantly contacting an aqueous slurry of the mineral with a peroxygen and a gas containing ozone at a pH from 5 to 12. Preferably, the peroxygen is incorporated into the slurry prior to contacting the slurry with a gas containing ozone. Optionally, the slurry may be pretreated with a chelating agent or subsequently bleached with a reducing agent.

Abstract: A process for producing aluminum hydroxide including the steps of:(a) dissolving colorant-containing aluminum hydroxide for forming a solution;(b) treating the solution for collecting colorant into solid phase material;(c) separating the solid phase material from the solution; and(d) precipitating aluminum hydroxide of improved whiteness from the solution.