Showing papers on "Sodium silicate published in 1969"

Fly ash based preformed support structures

Abstract: A PROCESS OF MAKING A PREFORMED SUPPORT STRUCTURE, SUCH AS BRICK, COMPRISING ADMIXING FLY ASH, A COARSE AGGREGATE, SODIUM SILICATE, AND HYDROCHLORIC ACID; SHAPING UNDER PRESSURE; DRYING AND FIRING AT ELEVATED TEMPERATURES.

Heat insulators for use in the casting of molten metal

Abstract: 1281684 Hot tops FOSECO TRADING AG 9 July 1969 [4 July 1968] 32019/68 Heading C3N [Also in Division D2] A composition suitable for use in the production of hot top linings or casting riser sleeves comprises 15-50%, preferably 20-30% by weight of fibrous material, 40-80% by weight of refractory material and 0A5-10% by weight of a binder material, the said fibrous material being wholly inorganic or containing up to 40% of its weight of organic fibrous material and the said refractory material consisting in whole or in part of bubble alumina, hollow silica microspheres, calcined rice husks or pozzolana. The inorganic fibrous material may be of calcium silicate, aluminium silicate, aluminosilicate, asbestos, slag wool, rock wool, mineral wool or metal fibres. The organic fibrous material may be wood pulp (paper pulp), wood flour, cotton waste, rag stock or waste synthetic staple fibre, e.g. nylon, polyester or acrylonitrile fibres. Further refractory materials specified are silica flour, olivine, chamotte, alumina or any refractory silicate. The grain size of the refractory material is preferably less than 325 B.S.S. mesh. The binder material may be sodium silicate, gums, cereal flours or thermosetting resins, e.g. phenol-formaldehyde, and urea-formaldehyde resins. A combination of phenol-formaldehyde and urea-formaldehyde resin is most suitable. The hot top linings and casting riser sleeves are produced by forming an aqueous slurry of the ingredients of the composition and expressing the liquid therefrom to deposit a body of the solid ingredients in the required shape. The shaped elements may be given a surface coating of a refractory material, e.g. zircon, to increase the resistance of the elements to metal penetration.

Production of insulating materials having low specific gravity

Abstract: Heat-insulating compositions are made by mixing porous plastic particles with an inorganic binder consisting of a suspension of water-containing particles of alkali metal silicate and inorganic fillers in an aqueous solution of an alkali metal silicate, and solidifying at a temperature above >0 DEG C. but below that at which the plastic sinters. Solidification can be assisted by extracting water down to a content of 20%, by treatment with carbon dioxide, or by the application of pressure. The porous plastic may be polyurethane, polystyrene, copolymers of styrene and acrylonitrile, acrylic acid, or butadiene, vinyl chloride, or copolymers of vinyl chloride and vinylidene chloride. Flame retardants such as inorganic halogen compounds or mixtures of chloroparaffins and antimony trioxide may be included. The alkali metal silicate powder is preferably sodium silicate containing 16-20% water and having an Na2O/SiO2 ratio of 1:2.0 to 1:4.0. The solution is of 15-60 DEG Be1 concentration, and the total water content varies between 25 and 75% of the weight of the silicate. Magnesia, talc, calcium carbonate, powdered asbestos, glass, quartz, zinc carbonate, sodium silicofluoride, or silica gel can be used as fillers in the ratio of 1:1 to 4:1 relative to the anhydrous silicate.

Corrosion prevention with sodium silicate and soluble zinc salts

Abstract: A PROCESS FOR RETARDING CORROSION IN METAL TUBES CARRYING WATER BY TREATING SAID TUBES WITH A COMBINATION OF SODIUM SILICATE AND A SOLUBLE ZINC SALT, AND WITH THE OPTIONAL ADDITION OF A CHELATING OR SEQUESTERING AGENT.

Method for manufacture of light weight aggregates

Abstract: A METHOD FOR THE MANUFACTUER OF COATED-TYPE LIGHT WEIGHT AGGREGATES WHICH COMPRISES MIXING A SILICIFEROUS MATERIAL, PARTICULARLY A MATERIAL SUCH AS FLY ASH WHICH IN ITSELF IS LOW IN PLASTICITY, WITH SLUDGE FROM A SEWAGETREATING PLANT AND, IF NECESSARY, WITH SODIUM SILICATE OR THE LIKE AS AN AUXILIARY BINDER, GRANULATING THE RESULTANT MIXTURE INTO PELLETS, AND BURNING THE PELLETS IN A ROTARY KILN.

Detergent tablet of amorphous sodium silicate having inherent binding properties,containing a surfactant,and method of making such tablet

Abstract: Amorphous sodium silicate having a burr-like structure imparting inherent binding properties thereto, is compressed into detergent tablets which contain a surfactant.

Refractory heat insulating materials

Abstract: 1,264,022. Thermal insulation. FOSECO INTERNATIONAL Ltd. 6 Oct., 1970 [6 Oct., 1969; 2 July, 1970], Nos. 49044/69 and 32217/70. Heading F2X. A refractory heat insulating material, suitable for the protection of turbine engine casings, is formed of a dry composition comprising inorganic refractory fibre and a water soluble inorganic binding agent, the composition being of a form of which the hardness, strength and density do not vary across the bulk material. Usually, though not necessarily, such a composition will be one in which the binding agent is homogeneously distributed. Preferably a wet or damp mixture of the ingredients is first formed and then dried by means of a drying method which does not cause migration of any of the components of the composition. Dielectric heating, infra-red heating or, preferably, microwave drying may be employed. The inorganic fibre is one or more of aluminosilicate, calcium silicate, asbestos, alumina, silica, zirconia and carbon fibres. The binding agent is silica sol, alumina sol, sodium silicate, potassium silicate, ethyl silicate or a metallic phosphate or borate. The composition may also include up to 10% by wt. of finely divided refractory material, e.g. alumina, silica, calcined rice husks, diatomite, kieselguhr, magnesia, silicon carbide, silicon nitride or fireclay. The insulating material may be faced or backed with a heat reflective layer such as aluminium foil, and it may if desired be faced with a refractory dressing. When used for lining turbine, aero engine or exhaust casings, the material may be secured in place by any convenient method such as adhesion, bolting or riveting, or by two or more such methods. A composite insulating material may be formed of two layers each of material according to the invention but of different densities. The lower density layer can even be honeycombed if desired. When used for lining a turbine or aero engine casing the lower density layer is preferably adjacent the casing. In a particular example, a preformed web of silica sol bonded aluminium silicate fibre, of thickness 25 mm., was adhered to the inside of a gas turbine casing with a sodium silicate based adhesive and riveted in place at the edges.

Heat of Annealing in Simple Alkali Silicate Glasses

Abstract: The enthalpy changes associated with annealing of glass were studied in simple and mixed alkali silicate glasses. The data indicate that during prolonged annealing the glass comes to a metastable equilibrium state and has a unique heat of solution which depends on its fictive temperature. The heats of solution of these glasses show a linear dependence on fictive temperature, and the magnitude of this dependence is related to the molar volume of the glass. The significance of these heat effects is discussed. The maximum heat effects which can occur on annealing sodium silicate glasses were measured and were approximately half as large as the enthalpy changes associated with the structural arrangements that occur during crystallization of these glasses.

Method of reducing the permeability of a thief zone

Abstract: A method for obtaining a flat injection profile for a fluid, such as a drive fluid used in an oil recovery operation, that is being injected into an interval of earth formation of nonuniform permeability by contacting the most permeable portions of the interval with a slurry containing a mixture of flexible solid fibers and a fiber-bonding agent, such as sodium silicate or a polyepoxide. An agent to precipitate or gel the bonding agent is then injected.

Thermal plugging with silicate solutions

Abstract: In an underground forward combustion process for recovering petroleum from earth formations, more uniform progress of the combustion front through a formation over a wide area is obtained by injecting a water solution of a water-soluble silicate after the combustion operation has been started. As the solution approaches the combustion front, evaporation of water results in formation of a cohesive, solid mass in the pores of the formation. Flow channels are plugged in this way, providing a more uniform progress of the combustion front. Preferably, the silicate solution is preceded and followed by water. If the formation contains exposed silica, sodium silicate can be formed in the formation by injecting sodium hydroxide.

Preparation of granular detergent compositions for automatic dishwashers

Abstract: GRANULAR DISHWASHING DETERGENT COMPOSITIONS ARE PREPARED BY DRY-MIXING SODIUM TRIPOLYPHOSPHATE AND CHLORINATED TRISODIUM PHOSPHATE, SPRAYING AQUEOUS SODIUM SILICATE THEREON TO FORM AGGLOMERATED GANULES, AND COOLING BY PASSING COLD AIR AT A TEMPERATURE NOT EXCEEDING 75*F. THROUGH A BED OF THE GRANULES.

Delignification and bleaching of cellulose pulp with oxygen gas in an allsaline medium in the presence of a protector

Abstract: A method of delignifying and bleaching a chemical or semi-chemical cellulose pulp with oxygen gas in an alkaline medium, preferably sodium hydroxide, and in the presence of a protector, the method being characterized in that the protector is selected from the group consisting of silica; an alkali metal silicate, such as sodium silicate; an alkaline earth metal silicate, such as magnesium silicate; an alkaline earth metal phosphate, such as magnesium phosphate; an alkaline earth metal oxide, such as magnesium oxide; an alkaline earth metal peroxide; an alkaline earth metal hydroxide or a material forming an alkaline earth metal hydroxide, such as magnesium hydroxide or a material forming magnesium hydroxide in situ; and a soluble salt of magnesium other than magnesium carbonate.

Method of preparing silica sol and product thereof

Abstract: A METHOD OF FORMING A SILICA SOL, INCLUDING ADDING SILICON METAL TO AN AQUEOUS SOLUTION CONTAINING AN INORGANIC ALKALI METAL COMPOUND AND HAVING A PH IN EXCESS OF ABOUT 11, SUCH AS A SODIUM HYDROXIDE, POTASSIUM HYDROXIDE, LITHIUM HYDROXIDE, SODIUM SILICATE, SODIUM METASILICATE, ETC., WHILE MAINTAINING THE TEMPERATURE BETWEEN ABOUT 50 AND 100*C. AND THEREAFTER MAINTAINING THESE MATERIALS IN CONTACT AT THE ABOVE TEMPERATURES FOR A PERIOD SUFFICIENT TO PRODUCE A PREDETERMINED SILICA-TO-ALKALI METAL OXIDE RATIO OR A PREDETERMINED PH IS ATTAINED. IF THE TEMPERATURE REACHES 100* DURING EITHER OF THE TREATING STEPS, THE PRODUCT PRODUCED LOSES SOME OF ITS HYDROPHILIC CHARACTER TO THE POINT OF BECOMING A HYDROPHOBIC, LOW VISOSITY SILICA SOL, WHEREAS AT LOWER TEMPERATURES, HYDROPHILIC, HIGH VISCOSITY SILICA SOLS ARE PRODUCED. IN ADDITION, BY MAINTAINING THE TEMPERATURE IN THE CRITICAL RANGE OF 90 TO 95* C., SUBSTANTIAL INCREASES IN THE EFFICIENCY OF CONVERSION OF SILICON TO SILICA ARE OBTAINED. THE SILICA SOL PRODUCTS OF THE INVENTION ARE CHARACTERIZED BY A VISCOSITY BELOW ABOUT 200 CP. FOR HYDROPHOBIC SOLS AND A VISCOSITY SUBSTANIALLY ABOVE 300 CP. FOR HYDROPHILIC SOLS AT SILICA CONTENTS OF ABOUT 50% AND BOTH ARE CHARACTERIZED BY FORMATION OF A COACERVATE OR PRECIPITATE WHICH DOES NOT HARDEN OR REDISSOLVE WHEN CONVENTIONAL GELLING AGENTS ARE ADDED THERETO.

Alkaline detergent composition

Abstract: A DISHWASHING DETERGENT COMPOSITION CONTAINING SODIUM SILICATE, PENTASODIUM TRIPOLYPHOSPHATE AND SODIUM FLUOSILICATE. THE LATTER ACTS TO PROTECT THE OVERGLAZE PATTERNS OF FINE CHINA. OTHER ALKALI METAL SILICATES, PHOSPHATES, CARBONATES, FLUOSILICATES AND CHELATES MAY BE USED. AN ANTISPOTTING AGENT, ACTIVE OXYGEN, OR CHLORINE BLEACHING AGENT (YIELDING HYPOCHLORITE CHLORINE) AND AN ORGANIC DETERGENT MAY ALSO BE PRESENT.

Firbrous refractory compositions

Abstract: 1278473 Fibrous refractory composition FOSECO TRADING AG 5 Jan 1970 [30 Jan 1969] 5257/69 Heading C3N [Also in Division D2] A refractory composition particularly for use in hot topping applications comprises at least two fibrous materials selected from calcium silicate fibres, aluminium silicate fibres and asbestos fibres, and either organic fibre or granular refractory filler or both, the maximum proportions of each ingredient in the composition being, by weight Calcium silicate 35% Aluminium silicate 55% Asbestos 35% Organic fibre 40% Granular refractory filler 50% and a binder. The binder may be colloidal silica, alumina or zirconia sols, aluminium phosphate, phosphoric acid, sodium silicate or an alkyl silicate. The particle size of any sol binder employed is preferably less than 100 A. The binder is preferably present in an amount 5A55 parts by weight dry binder per 100 parts by weight of the other ingredients. The aluminium silicate fibres should preferably have lengths in the range 12-250 mm., whilst the calcium silicate fibre, which may be synthetic pure calcium silicate fibre or slag wool, should preferably have lengths in the range 12-75 mm. The asbestos should preferably be the amosite type, have a water content of 2-3% by weight and having lengths in the range 9-18 mm. The organic fibre may be pulped newsprint, wood pulp, sawdust, cotton scrap, bagasse and synthetic materials such as rayon, nylon and acrylic fibres of which pulped newsprint is preferred. Mixtures of two or more fibres may be used. The granular refractory material may be fine silica, aluminium silicate, diatomite (preferably calcined), furnace aggregate, vermiculite, perlite, grog, chamotte, alumina, magnesia, silica, coke, olivine or chromite. The composition may be formed into sheets or slabs by conventional vacuum dewatering techniques and the finished article may be damp and flexible so that it conforms to the desired shape in situ in an ingot mould, head box or riser, or a hard dry rigid product.

Method of producing micro-perforated stainless steel sheets

Abstract: 1,173,179. Semi-permeable membrane; gas diffusion membrane. S. RUBENS. 29 Sept., 1967, No. 44370/67. Headings B1L and B1X. [Also in Divisions C7 and G2] Microperforated stainless steel sheet produced electrolytically (see Division C6-7) is impregnated with microporous-membrane-producing material to provide an element for use in dialysis or gaseous diffusion. Examples of such materials are polystyrene, co-polymers of polyvinylchloride and acrylonitrile, silicones, polyvinyl alcohol, cellulose esters and gelatine. Inorganic materials may also be used, for example, sodium silicate solutions, in which case the dried, treated sheet is subjected to acid to dissolve out the sodium and leave a microporous insoluble silica membrane. Thin fluorocarbon coatings may also be used to form permeable membranes.

Articles of bonded particulate material

Abstract: 1,150,541. Silicate compositions; foundry mould compositions. FOSECO INTERNATIONAL Ltd. 20 Jan., 1967 [27 Jan., 1966], No. 3620/66. Heading C3N. Particulate material (a) is mixed with aqueous alkali metal silicate (b), an ester of a polyhydric alcohol (c), and either dicalcium silicate or anhydrite, shaped, and allowed to harden. (a) may be sand. (b) may be sodium silicate wherein SiO 2 /Na 2 O is 2-3A3. (c) may be an ester of ethylene glycol, diethylene glycol, triethylene glycol, glycerol, or an ethylene oxide condensation product; and the ester may be an acetate, propanoate, or butanoate. Foundry cores and moulds may be made by this process. Reference has been directed by the Comptroller to Specification 1,029,057.

Method of chemical grout processing

Abstract: A COMPOSITION OF MATTER COMPRISING A SYNTHETIC RESIN AND A WATER SOLUBLE ORGANIC SOLVENT WHICH CAN DISSOLVE SAID RESIN, WHICH COMPOSITION MAY ALSO CONTAIN CEMENT AND/OR SODIUM SILICATE, IS INJECTED INTO SOIL. THE ORGANIC SOLVENT IS DISSOLVED AWAY BY THE GROUND WATER WHICH IS PRESENT IN THE SOIL AND THE REMAINING SOLID COMPONENT FILLS THE SPACES IN THE SOIL, WHEREBY WATER PATHS IN THE SOIL ARE BLOCKED.

Liquid self-hardening mixture for manufacturing foundry cores and moulds

Abstract: 1279979 Self-hardening foundry mould compositions TSENTRALNY NAUCHNO-ISSLEDOVATELSKY INSTITUT TEKHNOLOGII MASHINOSTROENIA 20 Jan 1970 [20 Jan 1969] 3112/69 Heading C3N A liquid self-hardenable mixture for making foundry cores and moulds comprises:-(a) a filler; (b) sodium silicate; (c) dicalcium silicate; (d) an anionic or non-ionic surface-active agent; (e) aqueous liquor obtained in the production of furanic resins; and (f) water. The aqueous liquor obtained as a by-product in the production of furanic resins contains furfuryl alcohol, phenol, formaldehyde, levulinic acid, methyl alcohol, maleic acid and salts thereof. The liquor is preferably present in an amount 0A3- 1-0 parts by weight. The filler is preferably quartz sand; the sodium silicate preferably has a specific gravity of 1A48 and a SiO 2 : Na 2 O molar ratio of 2A7 : 1; and the dicalcium silicate takes the form of self-crumbling slag from ferrochrome production. The anionic foaming agent may be an alkyl aryl sulphonate, alkyl sulphonate or alkyl sulphate whilst the nonionic foaming agent may be an oxy-ethylated alkyl phenol, alcohol, fatty acid, fatty amine, alkyl naphthol or mercaptan.

Method of applying a thermal insulating coating to an ingot wall

Abstract: A METHOD AND COMPOSITION FOR APPLYING THERMALLY INSULATING COATINGS TO INGOT MOLDS, BY SPRAY COATING A SUBSTANTIALLY NONAQUEOUS SUSPENSION OF REFRACTORY MATERIAL SUCH AS SILICA, ALUMINA, ZIRCONIA OR MAGNESIA, PASSING THROUGH A SCREEN HAVING A MESH OPENING OF 0.149 MM., A LOW DENSITY HEAT-INSULATING MATERIAL SUCH AS PEARLITE, DIATOMACEOUS EARTH OR WOOD FLOOR, PASSING THROUGH A SCREEN HAVING A MESH OPENING OF O.297 MM., A BINDER FOR GREEN STRENGTH WHICH IS FLOCCULABLE CLAY SUCH AS BENTONITE, AND A BINDER FOR DRY STRENGTH WHICH IS A SYNTHETIC RESIN OR SODIUM SILICATE OR GUM ARABIC, IN SUSPENSION IN AN ALCOHOL HAVING 1-3 CARBON ATOMS WHITE SPIRIT OR TOLUENE. THE SPRAYED PARTICLES AND THE SPRAYED SURFACE ARE GIVEN OPPOSITE ELECTRICAL CHARGES TO ATTRACT THE PARTICLES TO THE SURFACE.

Moulds and Cores for Casting

Abstract: 1,160,090. Mould-lining and core-coating materials. A. DUNLOP. 17 July, 1968 [18 July, 1967], No. 32995/67. Heading B3F. [Also in Divisions B5 and C3] Refractory moulds for precision castings, particularly of highly reactive metals, e.g. titanium and titanium base alloys, are produced from a slurry of refractory, binder and gelling agent which is subsequently heated to form a crazed structure, e.g. as a mould lining, which is then further strengthened by application of a further binder and impregnated with graphite. The slurry 20 may be applied to a poured or rammed refractory backing layer 17. Further binder may be applied by dipping into a liquid binder solution. Graphite impregnation may be achieved by placing the mould in a heated furnace and admitting a gaseous hydrocarbon thereto which is carbonized or by placing the heated mould in a container to which the hydrocarbon is admitted. Impregnation may also be achieved by incorporation of finely divided carbon into the liquid binder solution. The refractory material may be refractory oxides, silicates or carbon and the binder may be an alcoholic solution of phosphorus pentoxide, aqueous phosphoric acid, sodium silicate or hydrolysed ethyl silicate.

Process for the synthesis of zeolites

Abstract: 1,144,440. Sodium-potassium zeolite A. FARBENFABRIK WOLFEN VEB. 24 May, 1966, No. 23179/66. Addition to 1,065,993. Heading C1A. Sodium-potassium zeolite A, which, in its dehydrated form is of the formula- (0A9 Œ 0A1)[xNa 2 O + (1 - x)K 2 O].Al 2 O 3 .(1A92 Œ 0A1)SiO 2 wherein x is 0A05-0A99, is produced by subjecting to hydrothermal conversion at 50-100‹ C. for a period of at least half an hour a mixture the composition of which in terms of mole ratios of oxides is Na 2 O + K 2 O/Al 2 O 3 = 2A08-85 SiO 2 /Al 2 O 3 = 0A065-14 H 2 O/Al 2 O 3 = 250-1540 Na 2 O/Na 2 O + K 2 O = 0A05-0A99 In a first form of the invention this mixture is produced by mixing at least one potassium salt (e.g. chloride, nitrite, nitrate, sulphate), aqueous sodium aluminate solution, aqueous sodium silicate solution or silica sol, and optionally sodium hydroxide, the addition of the potassium salt optionally being postponed until after the commencement of heating of the mixture of other reaction components, and at latest half an hour before the termination of crystallization. In a second form of the invention the mixture is produced by adding potassium hydroxide to a mixture of sodium aluminate solution and sodium silicate solution or silica sol either after this last-mentioned mixture has been aged at room temperature for at least 10 minutes or after the commencement of heating of this mixture and at latest half an hour before the termination of crystallization.

Cleaning solution and method and apparatus for using the same

Abstract: A cleaning solution comprising water, about 2.5 to about 4.0 liquid ounces of a caustic and water solution having a density of about 11.67 pounds per gallon for each gallon of water, and about 1.5 to about 4.0 liquid ounces of a sodium silicate and water solution having a density of about 12.67 pounds per gallon for each gallon of water. The apparatus of the invention includes a bath, two separate tanks separately connected to the bath and having separate valves for independently metering the contents of the tanks into the bath as desired. The bath is preferably stationary and the tanks are preferably portable and easily attached and detached from the bath. A specific tank for use with the bath has a fill opening, a vent and a valve attached to the tank. Articles to be treated by the solution are placed within the solution in accordance with the method of the invention and the concentrations of hydroxide and silicate are periodically determined in a sample of the solution, and both additional caustic solution and the sodium silicate solution are metered into the bath to maintain desired concentration levels.

High temperature porous material

Abstract: 1,142,230. Porous refractories. DOULTON & CO. Ltd. 19 Dec., 1967 [19 Dec., 1966], No. 56738/66. Heading C1J. Porous refractories comprise ceramic particles bonded together with a composition consisting of an aqueous sodium silicate solution and calcium aluminate. Ceramic materials specified are alumina, magnesia, silica, zirconia, aluminosilicates and calcined, comminuted china clay.

Improvements in or relating to the Re-Heating of Steel Billets

Abstract: 1,171,283. Coated steel. G.K.N. GROUP SERVICES Ltd. 23 Feb., 1967 [25 Feb., 1966]. No. 8327/66. Heading B2K. [Also in Division C7] A process for inhibiting decarburization of steel bodies (e.g. ingots, blooms or bars) during heating (e.g. prior to hot working) comprises applying a coating comprising a suspension of china clay in an aqueous solution of an alkali silicate glass, optionally containing also a reducing agent such as aluminium powder and drying the coating prior to heating. For sodium silicate glass the ratio SiO 2 : Na 2 O is preferably greater than 2.5 to 1 and for a potassium glass the ratio SiO 2 : K 2 O is preferably greater than 2 to 1. In the Example the coating composition is 25% china clay suspended in an aqueous solution containing 37.8 % of a sodium silicate glass having a ratio SiO 2 : Na 2 O of 3.3 to 1 together with up to 1% of powdered aluminium. The suspension may be applied by dipping brushing or spraying and preferably provides a coating of 20 gms per square foot after drying.

Manufacture of Dimagnesium Aluminosilicate

Abstract: 1,154,799. Dimagnesium aluminosilicate. FUJI KAGAKU KOGYO K.K. 17 Feb., 1967, No. 7701/67. Heading C1R In the preparation of dimagnesium aluminosilicate, (AlO 2 Mg) 2 SiO 3 , 8 mols. caustic soda and 1 mol. sodium silicate are reacted with an aqueous aluminium salt solution equivalent to 1 mol. Al 2 0 3 , and an aqueous magnesium salt solution equivalent to 2 mol. MgO is reacted with the resultant mixture: the sodium silicate is added either (i) after addition of all the caustic soda, or (ii) after addition of 4 mols. caustic soda. The reaction may be carried out at 60‹ C., dimagnesium aluminosilicate being separated as a precipitate. Specified reactants are aluminium sulphate and magnesium sulphate or chloride.

A method of preventing or reducing scale and/or corrosion in water systems

Abstract: 1,141,032. Treating water. KINNIS & BROWN Ltd. 24 Feb., 1966 [24 Feb., 1965], No. 7990/65. Heading C1C. A method of preventing or reducing scale and/or corrosion in water systems in which the water in or or entering the system is of an acidic nature comprises contacting the water with sufficient magnesium carbonate (e.g. magnesite) to neutralize the original acidity of the water, and sodium silicate, either sequentially or as a mixture. The compounds may be crystalline, and the mixture may be in the form of balls, pellets and tablets, prepared by the method according to Specification 1,141,031, and also comprise dichlorophene as an algicide and a silicone as an anti-foam agent.