Showing papers on "Sodium silicate published in 1989"

Multinuclear NMR investigation of the formation of aluminosilicate anions

Abstract: The structure of simple aluminosilicate anions formed by the reaction of silicate and aluminate anions was investigated by {sup 29}Si and {sup 27}Al NMR spectroscopy. The extent of aluminosilicate formation was found to increase with increasing silicate ratio and increasing cation size. The first of these trends is attributed to the redistribution of Si with increasing silicate ratio to more acidic anions. The second trend is attributed to the formation of cation-anion pairs.

Evidence from alkali-metal NMR spectroscopy for ion pairing in alkaline silicate solutions

Abstract: Interactions between alkali-metal cations and silicate anions in silicate solutions were investigated by cation NMR spectroscopy. The concentration of cation-anion pairs was determined from the chemical shift and the resonance line widths. The concentration of ion pairs involving large anions increases with increasing cation size. For silicate solutions in which there is a distribution in cation size, the concentration of ion pairs exhibits a maximum with increasing cation size. This maximum is interpreted in terms of the selectivity of ion-pairing reactions.

Silica polymerization and other factors in iron control by sodium silicate and sodium hypochlorite additions

Abstract: Etude experimentale des effets du type de silicate, de la dilution et de methodes d'addition sur l'achevement du traitement d'eau souterraine par sequestration du fer

Liquid detergent compositions

Abstract: of EP0239195An aqueous liquid alkaline structured detergent composition comprising a nonionic detergent surfactant, a detergency builder, a dissolved sodium silicate, an alkaline agent and a structuring polymer agent, the amount of all dissolved sodium silicate material and the amount of all alkaline agent being such that the resultant amount of the alkali metal silicate is at least 10% by weight of the total composition and the weight ratio of the amount of free sodium cations to the amount of silicate anions expressed in terms of silicon dioxide being equal to or below 0.7:1, sufficient alkaline agent being present to provide the composition at an aqueous solution concentration of 1 % by weight with a pH value of at least 11.

Factors affecting hydrogen peroxide stability in the brightening of mechanical and chemimechanical pulps. II: Hydrogen peroxide stability in the presence of sodium silicate

Abstract: On etudie le mecanisme de stabilisation du peroxyde d'hydrogene par le silicate de soude en procedant a l'evaluation des effets de certaines variables sur la decomposition du peroxyde (pH, purete chimique, solubilite et concentration du metal de transition, concentration radicale libre, colloides organiques, ordre d'apparition du silicate et de la base, formation du «peroxysilicate»)

Thermal insulating fluid

Abstract: A thermal insulating fluid which is well suited for the insulation of steam injection wells comprises a heavy oil having an API gravity of not more than 15° and a water content of not more than about 5% by volume as a major liquid portion, a light oil as a minor liquid portion, a smectite-type clay in an amount sufficient to impart thixotropic properties to the fluid, calcium oxide in an amount sufficient to maintain gel strength at elevated temperatures and to inhibit light oil losses through evaporation, and hydrated amorphous sodium silicate with a SiO₂/Na₂O modulus ratio of about 3 to about 4 present in an amount sufficient to reduce thermal conductivity of said thermal insulating fluid.

Finely divided precipitated silicas with a high structure, process for their preparation and their use

Abstract: The finely divided high-structure precipitated silica, which has a… BET surface area (DIN 60132) of between 150 and 350 m /g… a compacted bulk density (DIN 53194) of between 60 and 120 g/l… a DBP number of between 3.0 and 4.0 ml/g… a particle size distribution of at least 70 % of 1 to 6 mu m. … It can be prepared by heating a mixture of water and sodium silicate to a temperature of 70 to 80 DEG C with stirring, metering into this mixture concentrated sulphuric acid until half of the alkali present is neutralised, treating the reaction mixture by means of a shearing unit and, if desired, simultaneously increasing the temperature to 86 +/- 5 DEG C, adding concentrated sulphuric acid after a period of 30 to 120 minutes at a higher speed until the pH of the silica suspension formed is 3.0 to 3.5, diluting, if desired, the silica suspension with water, separating off, if desired, the coarse portion by means of a centrifugal pump and a hydrocyclone, filtering off the silica using a known filtering device, washing the silica filter cake free of sulphate, redispersing the silica filter cake with the addition of water and using a stirrer to give a suspension having a solids content of 80 +/- 10 g/l, adding to this suspension, if desired, alkyldimethylbenzylammonium chloride, spray drying the suspension thus obtained and, if desired, milling the dried product. … The precipitated silica can be used as matting agents in paints either in uncoated or coated form.

Article having a corrosion inhibiting coating

Abstract: Corrosion inhibiting calcium-containing amorphous precipitated silica is described. The silica is prepared by admixing simultaneously in a reactor aqueous alkali metal silicate, e.g., sodium silicate, acidifying agent, e.g., hydrochloric acid, and a water-soluble source of calcium, e.g., calcium chloride. The product contains from 6 to 9 weight percent calcium (as CaO). The silica product may be incorporated into a coating composition used for corrodible metallic surfaces.

Method for solidifying asbestos

Abstract: PURPOSE: To prevent the scattering of dust from sprayed asbestos without deteriorating its intrinsic performance by infiltrating an aq alkali silicate soln into the sprayed asbestos layer and then infiltrating a specified curing agent into the layer to solidify the layer CONSTITUTION: An aq alkali silicate soln is applied and infiltrated into the sprayed asbestos layer A curing agent contg a polyvalent metal compd and/or an amino acid is then applied and infiltrated into the layer to solidify the layer The sodium silicate, potassium silicate, etc, in which the molar ratio of SiO 2 to M 2 O (M is Na, K, Li and NH 4 ) is controlled to 10-50 is exemplified as the silicate in the soln to be used A specified amt of the curing agent is uniformly applied by spray coating, brush coating or roller coating, and the surface is pressed by a trowel or a roller, if necessary Although the curing reaction of the surface solidifying agent rapidly proceeds at room temp the agent can be used for about 5 hr after preparation The agent is preferably allowed to stand for ≥1 day and cured COPYRIGHT: (C)1991,JPO&Japio

Method for forming a ceramic coating by laser beam irradiation

Abstract: A method for forming a ceramic coating on a substrate comprises immersing the substrate such as stainless steel in an aqueous solution containing a silicic acid compound such as sodium silicate and/or a metal salt of oxygen acid such as an aluminate, and irradiating the substrate with a laser beam. By this method, a dense and fine ceramic coating can be uniformly formed on the substrate without using an apparatus of large scale required in the gas phase method and without heating the system to a high temperature.

Method of preparation of a surface-coated metal-made ornamental article

Abstract: A metal-made ornamental article, such as watch cases and the like, is provided with a bilayered coating layer composed of an undercoating layer of a specified thickness formed from an aqueous colloidal solution of sodium silicate and silica sol in a specified proportion and a top-coating layer of a specified thickness formed by coating with a solution of a partial hydrolysis-condensation product of an organic silicate ester compound, such as ethyl silicate, followed by baking to effect curing of the coating layer.

Water-insoluble high temperature ink

Abstract: A composition to produce an adherent and water insoluble deposit on substrate surfaces. A coating material for these surfaces is described which can be applied at any temperature up to at least 2000 degrees F., with the resultant deposit being highly adherent and water insoluble after short drying times. This coating has a liquid phase formed from at least water, a pre-reacted lithium silicate, and a pre-reacted potassium silicate. It can also contain a sodium silicate. This coating can be expressed as being about 69 to about 79 wt. % water and about 21 to about 31 wt. % a mixture of R2 O and SiO2. The R2 O is selected from either a mixture of Li2 O and K2 O or from a mixture of Li2 O, K2 O and Na2 O. The R2 O and SiO2 typically have a molar ratio of about 0.24 to about 0.29, and the K2 O is about 35 to 85% of the total molar amount of the R2 O. When Na2 O is present, it is up to about 10% of the total molar amount of the R2 O. To this liquid phase is added a suitable pigment or other refractory material, at about 6-80 wt. % based upon the liquid phase. A range of compositions is discussed as well as typical results.

Refractory composite material and process for its fabrication

Abstract: Refractory composite material, in particular of the type with cellular structure and process for its manufacture. The material, exhibiting good physical and mechanical characteristics and good fire resistance, comprises a matrix of cellular structure consisting of a cured foam of an inorganic binder and inorganic structural or weight-reducing fillers. The binder is sodium silicate. This material can be applied more particularly to the production of sheets for thermal insulation and protection against fire.

Builder combination with a reduced phosphate content

Abstract: A builder salt combination for use in washing agents, which improves the secondary detergent power, comprises (A) 40 to 80 parts by weight of a mixture of sodium silicate having the composition Na2O:SiO2=1:0.9 to 1:1.6 and washing soda, the weight ratio of sodium silicate to washing soda being 4:1 to 1:2, (B) 0.2 to 1.5 parts by weight of sodium tripolyphosphate, and (C) 2 to 5 parts by weight of a (co)polymer of 100 to 50 wt.% of acrylic acid or methacrylic acid and 0 to 50 wt.% of maleic acid with a molecular weight of 5000 to 150000 in the form of the sodium salt.

Aqueous bleaching composition comprising sodium perborate tetrahydrate and aqueous detergent compositions containing the same

Abstract: A bleach formulation comprising an aqueous solution/suspension of sodium perborate tetrahydrate (preferably "fines") and a thickening agent and optionally and preferably one or more other ingredients of conventional detergent compositions, notably an aqueous sodium silicate solution.

Electrolytic method of and bath for stripping coating from aluminum bases

Abstract: A method of stripping coatings from aluminum base materials using an electrolytic solution comprising a hydroxy organic acid such as tartaric acid; an alkali metal carbonate such as sodium carbonate; an aluminum corrosion inhibitor such as sodium silicate; and remainder water.

Ceramic flux for welding low-alloy steels

Abstract: A ceramic flux for welding low-alloy steels contains calcined magnesite, synthetic slag containing two thirds of CaF2 and one third of Al2 O3, a component containing at least 95% of Al2 O3 in the alpha form, wollastonite, marble, barium fluoride, ferrotitanium, ferroboron, sodium silicate. The ratio of the total content of calcined magnesite, two thirds of synthetic slag and one half of wollastonite to the total content of the component containing at least 95% of Al2 O3 in the alpha form, one third of synthetic slag, one half of woolastonite and two thirds of sodium silicate ranging from 1.30 to 1.43 and the ratio of titanium to boron ranging from 11.2 to 30.1.

Effects of Sodium Silicate Exposure at High Temperature on Sintered α‐Silicon Carbide and Siliconized Silicon Carbide

Abstract: Sintered α-silicon carbide and siliconized silicon carbide were exposed to combustion off-gas containing sodium silicate vapors and particulates in a combustion test facility for 24 to 373 h at 900° to 1050°C. Degradation was evaluated by measuring dimensional changes, by measuring loss in strength due to changes in flaw population, and by evaluating surface corrosion morphology. It is suggested that passive oxidation and dissolution of the silica oxidation scale play an important role in the corrosion process. These mechanisms were enhanced by the continuous removal and replenishment of corrosive material by the high-velocity gas. These degradation phenomena caused surface pitting and an approximately 50% reduction in strength for both materials after long-term exposure (>100 h). Morphological evaluation suggested that the grain boundaries in the α-silicon carbide were oxidized more rapidly than the grains, while for the case of the siliconized silicon carbide the silicon phase was oxidized rapidly along with preferential oxidation of the silicon carbide grains parallel to the {0001} plains.

Coating composition to prevent corrosion on metals

Abstract: A novel, metal protective solution is described. This solution of two parts, the first part being a mixture of one aqueous potassium silicate and two aqueous sodium silicate solutions and the second part comprising approximately equal amounts of acetic acid, zinc oxide, copper sulfate, clay and sodium bicarbonate, is stable, relatively inert and has a long shelf-life. It may be applied to metal surfaces to prevent corrosion and rust from forming thereon.

Process for preparing a coloured granular alkali metal silicate

Abstract: The invention provides coloured granules (detergent speckles) which comprise an alkali metal silicate, which granules are coated with a colourant material. Preferably the coloured granules comprise a sodium silicate, in particular a metasilicate. Very good results are obtained with silicate hydrate granules, in particular a hydrate containing 5-6 water molecules per molecule of silicate in the crstal. The invention also provides a process for manufacturing the coloured granules.

Fire protected foamed polymeric materials and filler compositions

Abstract: Foam polymer compositions having outstanding resistance to exposure to flame comprise the product of reaction of a foamable composition and inorganic filler materials which include one or more of (A) microexplodable micron-sized particles having an internal phase of a non-­flammable gas releasing inorganic particulate material such as alumina trihydrate and an external phase of fusible inorganic material such as sodium silicate, (B) particulate, expandable alkali metal silicate, and optionally (C) a particulate inorganic fire retardant such as ammonium salt of a phosphate or polyphosphate. The foams are self-extinguishing, essentially non dripping, and generate only low levels of smoke when impacted directly with the flame of a blowtorch. The aforesaid filler materials can be incorporated also in non-foamed plastics, e.g. paints, for fire-proofing same.

Production of zeolitic catalyst.

Abstract: An economical method of manufacturing enhanced fluidization (low density) catalysts by in situ crystallization of zeolite in precursor microspheres of calcined kaolin clay. The precursor microspheres are prepared by spray drying a slurry of kaolin clay all of which is hydrated (raw or uncalcined), the slurry being flocculated as a result of the presence of an alkaline water soluble sodium silicate in sufficient amount to achieve a slurry in a flocculated rather than deflocculated state. The slurry is spray dried and calcined. The calcined microspheres are reacted with an alkaline solution to crystallize the zeolite (synthetic crystalline faujasite) and ion-exchanged.

Pumpable ceramic fiber composition

Abstract: A pumpable ceramic fiber composition having, by weight, from about 20% to about 30% of ceramic fiber, from about 5% to about 10% of a sodium silicate binding agent, from at least 1% to less than 5% of a binder migration retarding agent, from about 0.5 to about 2.5% of a viscosity modifying and lubricating agent, and from about 60% to about 70% of a liquid vehicle, preferably water. The pumpable ceramic fiber composition is resistant to deterioration under repeated freezing and thawing cycles.

Application of Gel Filtration Chromatography To the Study of Aqueous Silicate Complexes

Abstract: Pour etudier les solutions alcalines des silicates, une colonne Sephadex G15 est utilisee avec eluant NaCl a 0•1 mole

Surface-coated metallic ornamental article and method for the preparation thereof

Abstract: A metal-made ornamental article, such as watch cases and the like, is provided with a bilayered coating layer highly resistant against scratches and chemicals without decreasing the aesthetic value of the article. The coating layer is composed of an undercoat­ing layer of a specified thickness formed from an aqueous colloidal solution of sodium silicate and silica sol in a specified proportion and a top-coating layer of a specified thickness formed by coating with a solution of a partial hydrolysis-condensation product of an organic silicate ester compound, such as ethyl silicate, followed by baking to effect curing of the coating layer.