Sulfuric acid attack

The corrosion resistance of lead is due to the formation of a thin surface film of an insoluble lead salt that protects the metal from sulfuric acid and related compounds of any strength at ordinary temperatures. Even when (he temperature increases to nearly 100°C the rates of corrosion are still low. However, strong, hot sulfuric acid attacks lead rapidly, especially if the acid is flowing. 

Bromination of 10,10-dimethyl-2-aza-10-silanthrone (207) with NBS in acetic acid gave the 4-bromo derivative (30%), whereas in 80% sulfuric acid attack was in the 5- and 7-positions in the fused benzene ring (total yield 45%). Reduced yields in the presence of a radical initiator demonstrated that the reaction in acetic acid was not a homolytic process. The... 

Stable in air at ordinary temps burns in Oj forming NiO not affected by w decomps steam at red heat. Slowly attacked by dil hydrochloric or sulfuric acids attacked by nitric acid. Not attacked by fused alkali hydroxides (Refs 5 6). 

The flue gas exit stack should be checked for cold-end sulfuric acid attack, fouling front ash and expansion joint cracking. 

Recent Developments in Research on Biogenic sulfuric Acid Attack of Concrete (E. Vincke, J. Monteney, A. Beeldens, N. De Belie, L. Taerve, D. Van Gemert, W. H. Verstraete)... 

Vincke, E., J. Monteny, A. Beeldens, N.D. Belie, L. Taerwe, D. van Gemert, and W.H. Verstraete (2000), Recent developments in research on biogenic sulfuric acid attack of concrete. In RN. L. Lens and L. H. Pol (eds.), Environmental Technologies to treat. Sulfur Pollution — Principles and Engineering, IWA Publishing, pp. 515-541. 

Nickel is added to improve resistance to environmental and stress cracking corrosion. Molybdenum provides even greater resistance to corrosion and improves mechanical strength. Copper increases resistance to sulfuric acid attack. 

The sulfuric acid attacks limestone walls and marble statues. 

Chromic acid in aqueous sulfuric acid attacks the benzene ring in a large number of strychnine and brucine derivatives, leading to the isolation of products in which the aromatic ring has been oxidized away. Doubtless, as the low yields indicate, attack of the other, nonaromatic, portion of the molecules also occurs, but this is presumably so indiscriminate that the isolation of homogeneous products has so far failed. The following is a selection of the more important and interesting chromic acid oxidations. 

Strong acids, such as 96% sulfuric acid, attack the polymer rather severely weaker acids and a variety of inorganic bases are not detrimental. The polymer is inert to a wide variety of inorganic salt solutions, with some samples of coated metals having been exposed in salt water in the Gulf of Mexico for one year without deterioration. In fact, even the uncured polymer is remarkably resistant to a broad group of chemicals. 

HEXAHYDROCRESOL (25639-42-3) C,HuO Combustible liquid (flash point 149°F/65°C Fire Rating 2). Strong oxidizers may cause fire and explosions. Reacts with boranes, alkalis, aliphatic amines, amides, nitric acid, sulfuric acid. Attacks some plastics, rubber, and coatings. On small fires, use dry chemical powder... 

ALANINOL (78-91-1) Combustible liquid (flash point 145°F/63°C). Violent reaction wiili strong oxidizers, strong acids, isopropyl percarbonate, nitrosyl perchlorate. Incompatible with aldehydes, nonoxidizing mineral acids, cellulose nitrate (of high surface area), cresols, isocyanates, nitrates, nitric acid, organic anhydrides, phenols, sulfuric acid. Attacks aluminum, copper, zinc, or their alloys, and galvanized steel. 

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