Abstract: A process for the production of a black iron oxide pigment from Fe2O3 hematite iron oxide which may be an impure oxide produced by the “Ruthner” process or by other means, or which may be a mineral hematite. The process may be used to upgrade poor quality synthetic or natural hematite, or to improve their performance as red pigments, by conversion to black pigment with subsequent oxidation of the magnetite so produced back to hematite. The process uses a low temperature aqueous slurry reaction in which the hematite is contacted with a soluble source of Fe(II) ions in the presence of a soluble source of Fe(III) ions in an aqueous alkaline medium to convert the same to Fe3O4.

Abstract: A process for preparing a vinyl isothiocyanate comprises contacting a halogen-substituted allyl thiocyanate, in solution and at an elevated temperature, with an acidic material which is either an acid or a halide or oxyhalide of an inorganic acid. The halogen-substituted allyl thiocyanate may be prepared from a dihalogenated alkene. The vinyl isothiocyanate may subsequently be converted to a thiazole.

Abstract: A process for the treatment of aqueous acidic liquors containing dissolved aluminum and/or iron compounds to produce an aluminum and/or iron sulfate water-treatment product is characterized by the combination of steps comprising contacting the liquor with a basic material capable of reacting with the dissolved aluminum and/or iron compound to precipitate aluminum and/or iron values, separating the precipitate in the form of a cake or slurry from the remaining liquor, treating the cake or slurry with sulfuric acid to re-dissolve aluminum and/or iron values and to produce a solution of aluminum and/or iron sulfate and separating suspended solid matter from the solution. The liquor may be a waste product from industrial processes or may be a mine effluent and the process avoids the need to dispose of these to waste.

Abstract: The composition comprises a water dispersible colloidal siliceous material, such as a swelling clay, in intimate association with a low molecular weight water soluble high charge density organic polymer, such as a polyacrylic acid or a polyamine, the ionicity of the siliceous material being significantly modified by the charge on the polymer. The composition may be produced by reacting the siliceous material and the organic polymer in an aqueous phase system at a concentration, for example, of from 5 to 25% by weight of the polymer on swelling clay solids. The composition is suitable for use as a retention/drainage agent in paper or paperboard production, preferably after the addition of a conventional high molecular weight flocculating agent.

Abstract: A process for the production of an adsorbent suitable for use in the purification of edible oils such as soya oil comprising treating a layered clay mineral with a solution of a pillaring material such as a suitable aluminum cation so as to cause the adsorption of at least some of the pillaring material into the clay mineral and removing solvent to deposit pillaring material within the clay mineral, the process being characterized by the removal of at least some structural aluminum from the clay mineral by an acid treatment prior to contact with the pillaring material. The resulting pillared material, which can have a higher SiO.sub.2 :Al.sub.2 O.sub.3 ratio than normal as a result of the initial acid treatment can give chlorophyll adsorption capacity above 70% and even, in some instances, up to about 99%.

Abstract: Adsorbents suitable for use to remove aromatic or polyaromatic hydrocarbons from liquids such as oils may be produced from an acid-activated siliceous clay containing adsorbed oil by treating to carbonize the oil and to activate the carbon so produced on the surface of the clay. The carbonization and activation steps may be conducted by heating in the presence of an activating agent which may be zinc chloride. Preferably zinc chloride activated material is subsequently steam-treated.The invention is particularly useful to reduce the content of hazardous polyaromatic hydrocarbons, such as benzo(a)pyrene, from edible oils.

Abstract: Fluxes for aluminium brazing or welding may be produced by grinding the slag by-product of aluminium boron master alloy production. The grinding is preferably to below 75 microns size but particularly preferably to below 30 microns size. The fluxes may be mixed into water to produce a stable, mobile slurry which may be spray-applied to an aluminium work-piece.

Abstract: Small animal litter comprises an absorbent material containing an odor-reducing quantity of an aliphatic halo-nitro-bactericide such as those available under the Tradenames Bronopol, Bronidox or Myacide.

Abstract: The composition comprises a water dispersible colloidal siliceous material, such as a swelling clay, in intimate association with a low molecular weight water soluble high anionic charge density organic polymer, such as a polyacrylic acid or a polyamine, the ionicity of the siliceous material being significantly modified by the charge on the polymer. The composition may be produced by reacting the siliceous material and the organic polymer in an aqueous phase system at a concentration, for example, of from 5 to 25% by weight of the polymer on swelling clay solids. The composition is suitable for use as a retention/drainage agent in paper or paperboard production, preferably after the addition of a conventional high molecular weight flocculating agent.

Abstract: Pool or spa water can be monitored for dimethyl hydantoin content, as a residue of disinfection with halogenated hydantoin, by determining the quantity of base required to adjust the pH to 9.3. The pH may be judged by a suitable indicator for example thymol phthalein or thymol blue. The method can be applied either titrimetrically, or by comparison colorimetrically with standard solutions and may be modified for use in relation to other halogenated hydantoins. The method may be applied to the testing of pools for compliance with an advisory dimethyl hydantoin content limit and may be embodied in a kit for easy poolside use.

Abstract: A copper arsenate composition suitable for incorporation in a copper/chrome/arsenic wood preservative composition is made by reacting copper metal with a source of 5-valent arsenic such as arsenic acid under the oxidizing influence of hydrogen peroxide. The quantity of arsenic acid used may be made consistent with the arsenic to copper ratio required in the final wood preservative composition which may be made up by including a suitable source of chromium with the copper arsenate reaction product.

Abstract: Wood preservative compositions containing as active ingredients compounds of copper, of chromium and of arsenic are produced by mixing copper arsenate and sodium dichromate in an aqueous medium into which is introduced strong acid, for example sulphuric acid, effective to achieve a soluble product. The acid addition is preferably effective to reduce the pH to below 0. The composition so produced is a homogeneous paste which may be dissolved in water to working concentration and used for the preservation of wood by impregnation techniques.

Abstract: Ferrous sulphide is produced by forming a melt of a source of sulphur, suitably flotation grade iron pyrites, and a source of iron, suitably steel, in an electric induction furnace until reaction has ocurred, allowing a slag to form and removing the slag and pouring the residual ferrous sulphide product. Precautions are taken to protect the furnace circuitry from the pervasive effect of iron pyrites dust. The process may produce a ferrous sulphide product containing up to about 35% sulphur by weight with only low sulphur emission to the atmosphere.

Abstract: A racemate may be resolved into its enantiomers by stereoselective adsorption on a crystalline molecular sieve having an assymetric crystal structure for example zeolite ZSM11. The resolution may be assisted by the presence of an enantiomer of a compound separable from that of the racemate either preadsorbed on the molecular sieve or included in a polar solvent solution of the racemate to be treated. Resolution of an alkyl aryl sulphoxide racemate is exemplified.

Abstract: Boron compounds such as alkali metal or alkaline earth metal borates capable of forming hydrates or higher hydrates may be formed into shaped bodies by forming into a paste with water and allowing the water to be bound to form a solid shaped body. The bodies are useful as inserts into preformed cavities in structures, e.g. of wood, liable to insect, fungal or other infestation by virtue of the slow dissolution of the insert and the toxicity to such organisms of the boron compounds.

Abstract: Absorbent material comprising clay mineral particles, the particles comprising compacted masses of relatively smaller particles is found to have high absorbency which may be further increased by the use of additives such as silicates, pyrophosphates, swelling clays, polysaccharides or polyvinyl pyrrolidone. Preferred are smectites, attapulgite or sepiolite preferably in the form of particles in below 1.4 mm, preferably below 710 microns in the size range compacted into larger particles in the 710 micron to 4 mm size range. The absorbent particles are suitable for use as pet litter.

Abstract: Crystalline molecular sieve materials such as high silica zeolites are manufactured using an organic template comprising an optically active enantiomer such as an enantiomer of 3(.+-.) methyl piperidine -N,N-dimethyl bromide.A new zeolite materials is identified.

Abstract: The heat exchanger (1) comprises a plurality of coils (6.sup.1 -6.sup.5) of tubing of a flexible plastics material, the coils being of cylindrical conformation and of differing diameters each coil being mounted coaxially about the coil of next smaller diameter on an array of longitudinally arranged slat members (10) lying in spaced radial planes about the coil axis. The coils may be supported on the slat members by being received within recesses (11) in the slat edges and the slat members in turn are supported in similar manner on the coil of next smaller diameter. The tubing may be clipped into the recesses, and held therein, by virtue of the tubing or the slat members, or both being made of resiliently deformable material. Suitable material is a polyolefin or a polyvinyl material suitably a polyhalocarbon material where corrosion resistance is required. In use the flow of heat exchange fluid longitudinally through the coils is preferably countercurrent to the flow of fluid over the coils.

Abstract: A process for the manufacture of adsorbent clay mineral particles comprises first selecting clay mineral particles smaller than 2 millimeter in size, drying the clay mineral particles to a moisture content not exceeding 15% by weight and mixing the dried particles with from 0.2% to 5% by weight of a water dispersible colloid in water to form a mixture having a final moisture content not exceeding 15% by weight. The mixture is compacted in a press and the compacted material broken into masses of particles larger in size than the selected clay mineral particles and in the 710 micron to 4 millimeter size range. The product of the process is useful for example as a litter.

Abstract: In the fluidized bed chlorination of oxidic materials, for example minerals such as bauxite, tantalite, columbite, wolframite or scheelite, the separation of metal values giving vaporous chlorides at the reaction temperature is enhanced by maintaining a zone substantially free of chlorine in the fluidized bed, for example a zone at least 0.25 m in depth measured from the expanded bed surface. A high aspect ratio bed and counter current movement of the bed matter and the chlorine within the bed are preferably used.