Showing papers on "Aluminium hydroxide published in 2002"

Preparation of Zr-Containing Layered Double Hydroxides and Characterization of the Acido-Basic Properties of Their Mixed Oxides

Abstract: Multicomponent M(II)/Al/Zr layered double hydroxides (LDHs) with M(II) = Mg, Ni, and Zn, exhibiting single hydrotalcite-like phases by XRD, were obtained by coprecipitation at constant pH = 10. The...

Microstructures and mechanical properties of engineered short fibre reinforced aluminium matrix composites

Abstract: Aluminium matrix composites have been fabricated by squeeze casting into short fibre preforms modified on the basis of a phase contiguity model to improve mechanical performance. Fibre junctions were created in a planar random alumina fibre array by (a) sintering, (b) phosphoric acid treatment, (c) phosphoric acid/aluminium hydroxide (P/Al) treatment and (d) infiltration with alumina powder and sintering. The microstructures and mechanical properties of these composites were examined systematically. The results indicate that using phosphoric acid solution itself to create inter-fibre bonds in the preform gave rise to very low composite strength and ductility compared with that resulting from the as-received preform. This is mainly due to the severe damage to the fibres caused by chemical reaction. By employing the P/Al binder to create the cross-links, the composites reinforced with laboratory-made preforms yielded higher tensile strength relative to the uniform fibre reinforced composites without any sacrifice to the ductility and elastic modulus.

Optical cable with improved tracking resistance

Abstract: The present invention is concerned with an optical cable with improved tracking resistance comprising at least one optical fiber and an outer sheath which comprises a polymeric material, characterized in that the polymeric material forms a matrix for the sheath and consists of a multimodal olefin polymer obtained by a coordination catalyzed polymerization, and in that the total composition of the sheath comprises 15–40% by weight of a metal hydroxide, preferably magnesium hydroxide and/or aluminium hydroxide, and 0.01–0.9% by weight of carbon black.

Interface modification and characterization in linear low-density polyethylene highly loaded with aluminium hydroxide

Abstract: Fire-retardant linear low-density polyethylene (LLDPE) composites were prepared by combining this polymer with uncoated and surface treated forms of aluminum hydroxide (Al(OH) 3 ). The poor toughness and ductility of polyethylene highly filled with Al(OH) 3 can be significantly improved by addition of a small amount of silicon oil. It is found that silicon oil improves elongation at break of the composite remarkably, but this is accompanied by the deterioration of tensile strength. Silane crosslinked polyethylene substituting for polyethylene as the matrix in Al(OH) 3 -filled polyethylene improves the tensile strength of the composite. Fractured surface analysis and limiting oxygen index (LOI) of the composites were also studied. Possible mechanisms accounting for these effects are discussed.

Process and equipment for preparing aluminium polychloride

Abstract: A process for preparing aluminium polychloride from hydrochloric acid and aluminium hydroxide includes such steps as blowing appropriate quantity of chlorine gas into the mixed solution of hydrochloric acid and aluminium hydroxide, reaction of chlorine gas on water in the solution to generate hydrochloric acid and hypochlorous acid as catalyst for next reaction, and reaction of hydrochloric acid on aluminium hydroxide to generate aluminium hydroxychloride. Its advantages are simple process and equipment, short period, and high sterilizing, seaweed-killing and decolouring function. The productis an efficient water deaner.

Cement accelerator and method

Abstract: An alkali-free accelerator for sprayed cementitious composition, such as concrete, is prepared by dissolving aluminium sulphate in water and amorphous aluminium hydroxide in water optionally containing amine, and adding at least one stabiliser which is glycolic acid, and optionally at least one defoaming agent.

Cu/Zn/Al catalyst for methanol synthesis

Abstract: Disclosed is an Cu/Zn/Al-catalyst containing copper oxide and zinc oxide as catalytically active components and aluminium oxide as thermostabilising component. The catalyst is characterized in that the Cu/Zn atomic ratio is <2.8 and the aluminium oxide component is obtained from an aluminium hydroxide sol.

Catalyst for methanol synthesis and other reactions

Abstract: A method for the production of a Cu/Zn/Al catalyst, comprising copper oxide and zinc oxide as catalytically-effective substances and aluminium oxide as a thermostabilising substance is disclosed. Dissolved compounds, in particular, aluminium, copper and zinc salts are subjected to: a) a first precipitation with an alkaline solution or an alkaline aluminate/aluminium hydroxide sol, b) on completion of the precipitation, an aging of the first precipitate is carried out at approximately 20° C to 100° C, preferably 40° C to 90° C, over about 0 to 5 hours, c) in a second precipitation step, a solution of compounds of copper, zinc and optionally, aluminium, with a different Cu/Zn atomic ratio to step a), is added to the precipitate obtained in step b) along with an alkaline solution or an alkaline aluminate/aluminium hydroxide sol, d) an aging of the obtained second precipitate is carried out at about 20° C to 100° C, preferably 40° C to 90° C, over about 0.5 to 5 hours, e) the second precipitate obtained in step d) is separated from the solution and washed to remove alkaline ions and f) the washed second precipitate is then dried and subjected to a thermal treatment (calcination) at about 250° C to 400° C.

Heavy oil hydrogenation conversion catalyst and its preparing method

Abstract: The present invention discloses a kind of catalyst for hydrogenizing treatment, especially hydrogenizing treatment, especially hydrogenizing treatment of heavy oil and residual oil, and its preparation. The catalyst has high metal dispersity, large specific surface area and high hydrodenitrification and hydrodecarbonization activity. The catalyst is prepared with one kind of titanium containing aluminium hydroxide as material and through complete mixing and kneading process. The catalyst is easy to form and low in cost.

Binding geopolymeric mixture

Abstract: A Binding geopolymer mix, hardening at temperatures from 15 to 95 degrees C, designed for the production of paste, malt and concrete consisting of 35.01 to 93.9% by weight of fly ash with a specific surface of 100 to 600 m /kg, 0 to 40% by weight of material with a specific surface of 200 to 600 m /kg, selected from a group composed of ground Portland clinker, granulated blast-furnace slag and 5 to 15% of an alkali activator, for example a mix of sodium and/or potassium silica glass and NaOH or KOH, expressed as % by weight of Na2O or K2O, with a ratio of SiO2/Na2O or K2O equalling 0.1 to 1.0, and 1.1 to 9.99% by weight of aluminous admixtures containing at least 35% by weight of Al2O3, for example calcium aluminate, sintered aluminous cement, gibbsite, boemite, anhydrous Al2O2, calcinated or non-calcinated bauxite, aluminous clay, calcareous clay, aluminium hydroxide or mica. Advantageously the aluminous admixture should have more than 50% of particles smaller than 60 microns.

Preparation method of high-purity nanoaluminium oxide

Abstract: The preparation method of high-purity nanometer alumina includes the following steps: adopting high-purity organic aluminium alcoholate and making it produce hydrolysis reaction to produce intermediate product aluminium hydroxide at 45 deg.C-90 deg.c in the presence of inorganic acid or organic acid, drying the aluminium hydroxide at 105 deg.C, and roasting at 400 deg.C-950 deg.C so as to obtain the gamma-Al2O3 whose grain size is 8nm-20nm, form is made into ball and purity is greater than 99.99%.

Prepn of high-purity alumina

Abstract: The present invention features that through the reaction of choline and pure aluminium to produce aluminum cholinide, hydrolyzing cholinide to produce aluminium hydroxide and choline, washing, filtering, calcining and grinding aluminum hydroxide, high-purity alpha alumina is prepared. The present invention has the advantages of high product purity, environment friendship, no pollution, low cost, etc. The high-purity alumina may be used in high-voltage sodium lamp tube, light-emitting RE material, high-grade grinding material, fine ceramics and other fields.

Heavy and residual oil hydrogenating treatment catalyst and its preparing method

Abstract: The present invention dislcoses a kind of catalyst for hydrogenizing treatment, especially hydrodesulfurization of heavy oil and its preparation. The catalyst has one kind of non-expensive and environment friently titanium containing aluminum hydroxide as carrier. The titanium containing aluminium hydroxide, metal salt and other material are kneaded to disperse metal, and all materials are prepared into the catalyst through mixing, kneading, extrusion and high temperature activation. The catalyst is easy to form, low in cost and proper in acidity, and has excellent hydrodesulfurization activity and good hydrodenitrification and hydrodecarbonization activity.

Vaccine composition comprising at least two valences, one enhanced with adjuvant and not the other

Abstract: The invention concerns a vaccine composition comprising two valences; (i) a first valence which is adjuvant-enhanced with aluminium hydroxide and (ii) a second valence which contains a polysaccharide of bacterial capsule comprising one or more -O- acetyl groups and which is not adsorbed with aluminium oxide due to the presence of a protecting compound which may be a phosphate, a citrate or a carbonate and which prevents said adsorption. The first valence can be any vaccine valence. In one particular embodiment, the vaccine composition contains (i) the Hepatite A valence, adsorbed on aluminium hydroxide and (ii) the typhoid fever valence formed by the polysaccharide Vi of the Salmonella typhi capsule.

Comprehensive utilization of waste from aluminium smeltery

Abstract: The present invention uses waste slag recovered in the course of refining aluminium in aluminium plant, waste sulfuric acid produced by using electrochemical process to treat surface of aluminium section material and waste sodium hydroxide as raw material to prepare aluminium ammonium sulfate, sodium aluminate and aluminium hydroxide, etc. which are chemical products with extensive application range.

Macroreticular alumina carrier containing Si and Ti and its preparing process

Abstract: A macroreticular alumina carrier containing composite Ti-Si assistant is disclosed, which can be used to prepare macroreticular hydrocatalyst or hydrotransfer catalyst It is prepared by introducing Si-contained compound and cheap Ti-contained compound to the process for preparing aluminium hydroxide Its advantages include uniform dispersion of SiO2 and titanium oxide on surface of alumina, highpeptization, 10-15 mm of average pore diameter, and stronger surface acidity

The effect of the order of reagent addition on the settling rate of aluminium hydroxide in the Al(III)-Na2CO3 system

Abstract: The effects of several factors on the settling rate of aluminiumhydroxide were investigated during chemical coagulation using aluminium salts. Experimental variables were pH, aluminium (III) concentration and the order of addition of reagents. Experiments were carried out at pH 5–8 and rapid settling was achieved when aluminium (III) solutions were added to Na2CO3 solutions near neutral pH, close to the minimumsolubility pH of Al(OH)3. For a narrow range of total Al concentration where Al(III) species were supersaturated with respect to the solid phase, Al(III)-added-to-carbonate type mixtures yielded a higher settling rate than mixtures obtainedby the reverse order of reagent addition. The results were interpreted by comparing the rates of formation of polymer andsolid (amorphous Al(OH)3) phases. It was concluded that Al(III) coagulants should be added to water containing natural or artificially incorporated carbonate alkalinity for rapid settling of Al(OH)3 flocs.

Process for separating oil, water and solid from oil-contained float slegs

Abstract: A process for separating oil, water and solid from oil-contained floating dregs includes such steps as acidifying the floating dregs to pH=2-3, heating to 75-85 deg.C for decomposing aluminium hydroxide particles into soluble Al ions, so oil in floating dregs quickly floating up and solid suspended in floating dregs depositing, layering aside for 4 hr, discharging the aqueous solution under oil layer into a neutralizing pool, then adding alkaline substance for reaction on the said Al ions to generate aluminium hydroxide deposit, and press-filtering to separate water and solid.

Prepn. of retardant for magnesite binding material

Abstract: The retarding agent of magnesite cementing material is made up by using (wt%) water 25-35%, aluminium hydroxide 20-30%, tartaric acid 10-20% and phosphoric acid 25-35%. It can effectively delay initial setting time of slurry material, and can raise water-proof property of product.

Fine aluminium hydroxide

Abstract: The invention relates to an aluminium hydroxide having an average particle size in the range of 2 to 4 µm and a specific surface area according to BET in the range of 8 to 12 m 2 /g which is obtained by ball-milling.

Solid pharmaceutical preparation

Abstract: PROBLEM TO BE SOLVED: To provide a stable omeprazole-containing pharmaceutical preparation in which decomposition and discoloration are suppressed over a long period. SOLUTION: The solid pharmaceutical preparation is obtained by coating a nucleic composition comprising omeprazole or its salt and a buffer composed of a coprecipitate of a polyvalent metal hydroxide and a carbonic metal salt with at least one kind of enteric polymer selected from cellulosecarboxyalkyl ethers and (meth)acrylic polymers. The buffer may be composed of a coprecipitate of aluminium hydroxide and a carbonic metal alkali salt (particularly a coprecipitate of aluminium hydroxide and sodium hydrogancarbonate). The enteric polymer may be composed of a carboxymethyl-1-4C alkylcellulose, a methacrylic acid-acrylic 1-4C alkyl ester, or the like. The nucleic composition may further contain a basic amino acid or its salt. COPYRIGHT: (C)2003,JPO

The Adsorption of Anionic Surfactants by Iron(III) and Aluminium Hydroxides

Abstract: The adsorption of sodium dodecyl sulphate and sulphanol NP-3 by iron(III) and aluminium hydroxides was studied. The applicability of the Langmuir, Freundlich and Hill–de Boer adsorption equations for the description of the adsorption isotherms obtained experimentally was verified. Values of various parameters characterising the adsorption of the anionic surfactants investigated by iron(III) and aluminium hydroxides have been calculated. These allowed assumptions to be made about the adsorption mechanism. The possibility of using air as an adsorbent for anionic surfactants was studied.

Alumina pellets, catalyst supports, catalysts or absorbent containing same and methods for preparing same

Abstract: The invention concerns alumina pellets, obtained by dehydrating aluminium hydroxide or oxy-hydroxide, sintering the alumina thus obtained, subjecting the pellets to hydrothermal treatment and calcining, characterised in that: they have a specific surface ranging between 90 and 220 m2/g; they have a V?37A? ranging between 40 and 65 ml/g, preferably between 45 and 60 ml/g; they have a V200A not less than 12 ml/100g, preferably not less than 15 ml/100g, more preferably not less than 18 ml/100g; and they have a specific surface / V200A ratio not more than 10, preferably not more than 8.5, more preferably not more than 7. The invention also concerns a catalyst support, an adosrbent material and a catalyst made of such pellets. The invention furthr concerns methods for preparing said pellets.