Aluminium hydroxide

About: Aluminium hydroxide is a research topic. Over the lifetime, 2043 publications have been published within this topic receiving 22032 citations. The topic is also known as: Al(OH)3 & Amphojel.

Method for energy-economical exploitation of aluminium containing rocks and minerals

Abstract: Method for energy economic utilization of aluminium containing rocks and mineral for manufacture and isolation of valuable minerals. The aluminium containing rocks are in a first process step comminuted and dissolved in a mixture of CO2 and water under pressure at a pH in the range 3-7 and a temperature of about 300 0C and a pressure in the range 1-150 bar, the aluminium hydroxide thereby being directly precipitated and separated from the solution together with any compounds of iron and magnesium as well as any undissolved material. Reaction products in solution comprising both SiO2 and Ca2+ ions are continuously removed from the first process step while additional CO2 and H2O are continuously added so that the reaction takes place in absence of equilibrium. SiO2 and CaCO3are precipitated in subsequent process step at a pH higher than in the first process step.

XPS–SIMS Surface Characterization of Aluminovanadate Oxide Catalyst Precursors Co-Precipitated at Different pH: Effect of Calcination

Abstract: X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed in a comparative study of the surface physical and chemical state of aluminovanadate oxide catalyst precursors (V–Al–O), which were precipitated in the range of pH from 5.5 to 10, after drying and calcination. Core-level photoelectron spectra, X-ray induced Auger and valence band spectra of the samples were measured so as to quantitatively evaluate the surface concentrations of the catalyst components. The binding energy shifts of the respective O 1s, V 2p and Al 2p lines were determined as a function of pH and analyzed in terms of the initial state effect related to the atomic charge and Madelung potential. The surface of the catalysts was composed of aluminum hydroxide/oxyhydroxide and of dispersed vanadium oxide species. Increasing pH was found to result in a monotonic variation of the elemental surface composition, modification of the valence band, progressive hydroxylation of the surface and increasing dispersion of vanadium oxide species. Increasing pH was also accompanied by an increase in the abundance of V4+ species, specific surface area and reducibility. Calcination in air at 500 °C gave rise to surface segregation of vanadium, changes in the valence band and partial dehydroxylation. The structural transformations in vanadium oxide species and aluminium hydroxide support and their interaction were accompanied by an increasing abundance of V–O–Al bonds. The net result of the restructuring was a decrease in the specific surface area and reducibility of the calcined catalysts. The enhancement of the catalytic activity in propane oxidative dehydrogenation demonstrated by V–Al–O samples with increasing precipitation pH and after calcination was in good correlation with a growing population of the V4+ states and increasing nucleophilicity of oxygen sites.

Carbon monoxide adsorbent

Abstract: A carbon monoxide adsorbent comprises the following raw materials, by weight: 38 to 42% of cuprous chloride, 18 to 23% of 13X molecular sieves, 8 to 10% of aluminium hydroxide, and 28 to 35% of purified attapulgite powder. The adsorbent is produced by the following steps: a. the 13X molecular sieves are baked in a 200 DEG C oven for 120 to 150 minutes; b. the four raw materials are mixed into a mixed material, which is put into a kneader, purified water, the weight of which is 10% of that of the mixed material, is added into the kneader for kneading for 20 to 25 minutes, and kneaded material is obtained; c. the kneaded material is then processed by an strip extruder into strip-shaped objects with sizes between phi 3 mm * 8 mm and phi 3 mm * 15 mm; and d. the strip-shaped objects are put into the oven, baked at a temperature between 300 and 320 DEG C for 180 to 200 minutes, then taken out, and made into the carbon monoxide adsorbent after natural cooling. The carbon monoxide adsorbent is scientific in combination. Especially by adding 200 mesh purified attapulgite powder which undergoes crushing, purification, ultrafine processing and activation processing, the carbon monoxide adsorbent is improved in adsorption capability and substantially lowered in cost. The price of the carbon monoxide adsorbent is two thirds of those of similar products.

Magnesium-Containing Antacids to Patients with Uremia—An Intoxication Risk

Abstract: Twelve uremic patients were loaded with an-tacidum perorally under standardized conditions. In paired control tests, aluminium hydroxide alone or aluminium hydroxide + 0.5 g magnesium carbonate/24 hours were administered. As early as after 3–5 days, a significant increase in serum magnesium could be observed which indicated resorption and impaired magnesium excretion. Because of the danger of magnesium intoxication, only pure aluminium hydroxide preparations are recommended in the treatment of uremia with hyperphos-phatemia or gastritis.