Thermal decomposition, aluminum hydroxides

Hydroxides, hydroxy carbonates, and hydrates of aluminum, calcium, and magnesium that potentially meet these requirements are shown in Table 7.1, together with relevant thermal properties and gaseous products evolved on decomposition. However, of those in commercial use, aluminum hydroxide makes up about 90% of the market by tonnage, with magnesium hydroxide and basic magnesium carbonate products being used in niche applications. 

By reacting aluminum hydroxide with oxalic acid, basic aluminum oxalate can be produced, which is thermally stable to 330°C, losing 51% of its mass on decomposition at temperatures above 450°C. It is reported to have a flame-retarding and smoke-suppressing action similar to ATH, but because of its increased thermal stability, it can be used in polyamides and thermoplastic polyesters. However, unlike magnesium hydroxide, in these polymers it does not cause hydrolytic degradation.2... 

Methyl />-tolyl sulfone has been prepared by oxidation of methyl 7>-tolyl sulfide with hydrogen peroxide 4 r or ruthenium tetroxide,6 by alkylation of sodium -toluenesullinate with methyl iodide 7,8 or with methyl potassium sulfate,9 by decarboxylation of -tolylsulfonylacetic acid,7 by thermal decomposition of tetramethylammonium -toluenesulfinate,10 by reaction of cw-bis-(%tolylsulfonvl)-ethene with sodium hydroxide (low yield),11 by the reaction of methanesulfonyl chloride with toluene in the presence of aluminum chloride (mixture of isomers),12 by... 

The 1,3,5-triazine ring of melamine (1,3,5-triazine-2,4,6-triamine, l) is very stable and is cleaved only under very vigorous conditions.7,8 When melamine is heated with potassium carbonate or a mixture of sodium and potassium carbonate at 375 450°C in an aluminum vessel, the corresponding alkali cyanates 2 are formed by ring fission.9 A similar conversion is achieved with potassium hydroxide at about 250 °C.8 10 Thermal decomposition of melamine occurs on heating above 600CC,7 and on reaction with sodium amide and carbon at 760-850°C, alkali cyanides are formed.8... 

Kerr (d) has shown that during the thermal decomposition of ammonium Y zeolite at 500 °C there is a loss of aluminum if a deep bed geometry is employed. In the particular material that Kerr studied, sodium hydroxide treatment of the deep bed sample led to the increase... 

Microporous solids with surface areas in the range of 400 m /g or larger can be prepared in several ways. Controlled thermal decomposition of silica gel or aluminum hydroxides to AIO(OH) and then to the 7- or r/-phases of alumina produces such high-surface-area materials. The so-called sol-gel method, which uses both aluminate and silicate ions or aluminum and silicon alkyl compounds at a well-controlled hydrogen ion concentration, produces crystalline microporous solids that... 

Anhydrous aluminum nitrate [13473-90-0] is covalent in character, easily volatilized, and decomposes on heating (22). Hydrated aluminum nitrate is used in the preparation of insulating papers, on transformer cote laminates, and in cathode-ray tube heating elements. Solution of aluminum hydroxide through digestion of cote materials in nitric acid has been proposed in aluminum extractive metaUuigy. The resulting solution of aluminum nitrate is separated from other metal ions, and the aluminum oxide is recovered by thermal decomposition of the aluminum nitrate solution (23,24). 

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