Lead, corrosion

Lead-copper alloys Lead corrosion Lead crystal Lead cyanide... 

The mechanisms of lead corrosion in sulfuric acid have been studied and good reviews of the Hterature are available (27—30). The main techniques used in lead corrosion studies have been electrochemical measurements, x-ray diffraction, and electron microscopy. More recendy, laser Raman spectroscopy and photoelectrochemistry have been used to gain new insight into the corrosion process (30,31). 

Bullock, K. R., Electrochemical and Spectroscopic Method of Characterising Lead Corrosion Films , J. Electroanal. Chem., 222, 347-366 (1987)... 

Bullock, K. R., Trischan, G.M. and Burrow, R. G., Photoelectrochemical and Microprobe Laser Raman Studies of Lead Corrosion in Sulphuric Acid , J. Electrochem. Soc., 130, 1283 (1983)... 

Boffardi, B. P. and Sherbondi, A. M. Control of Lead Corrosion by Chemical Treatment, Paper 445, Corrosion 91 NACE Conf., Cinncinnati, Mar. 11-12 (1991)... 

Beccaria, A. M. e a ., Investigation on Lead Corrosion Products in Sea Water and In Neutral Saline Solutions , Werksloffe und Korros., 33, 416-420 (1982)... 

For environments in which tin is less readily corroded than lead, corrosion resistance of the alloy decreases as the lead content increases the decrease may, in some circumstances, be sharp at a particular composition. In the more corrosive media, such as nitrite solution, a sharp increase of corrosion rate is observed as the lead content increases beyond 30waters with low contents of dissolved salts, the corrosion rate increases slowly with lead content up to about 70% and then rises more steeply, but in the general run of supply waters the ability of lead to form protective insoluble anodic products is helpful to the durability of solder. Selective dissolution of tin has been... 

Lead. Ancient lead objects excavated from the ground are often affected by ions in the groundwater and become covered by a white layer made up of a wide range of lead corrosion products (see Table 45). Sometimes, however, the early formation of a corrosion layer of cerussite (composed of lead carbonate), provides the metal with a protective coating that prevents the progress of the corrosion process. 

Quantitative data on the nationwide range of lead levels in drinking water drawn from the tap (which would include lead corrosion by-product) were insufficient to assign a national value at the time of the 1991 EPA publication. One set of data comprised of 782 samples taken in 58 cities in 47 states shows that the average lead level in tap water was 13 pg/L with 90% of the values below 33 pg/L (EPA 199 Id). 

Joiret S, Bernard MC, Costa V (2008) Assessing indoor lead corrosion using Raman spectroscopy during electrochemical reduction, 8th International Conference of Infrared and Raman user s Group, Vienna (Austria), to be published in http //www.e-preservationscience.org... 

For use in medicine he directs to use only the first two preparations, though others are used in chemistry. He explains further the preparation of the waters above employed which are merely water solutions of salts named. The mortification of copper, lead, mercury and other metals is similarly described, with products such as verdigris, white lead, corrosive sublimate, or the various oxides, etc. In some cases, as with gold, the processes are elaborate but the fancied results are not capable of rational interpretation.7... 

SOD lead corrosion—test developed by Exxon to measure the corrosiveness of lubricating oils. A small lead panel of known weight and a copper panel (as catalyst) are attached to a spindle, which is immersed in a tube of the lubricant and rotated. Air is introduced at the bottom of the tube and allowed to bubble up through the sample. The weight loss by the lead panel after a specified period of time is a measure of the corrosivity of the oil. 

Raychaudhuri, M.R. and Brimblecombe, P. (2000) Formaldehyde oxidation and lead corrosion. Studies in Conservation, 45,... 

Tetreault, J., Sirois, J. and Stamatopoulou, E. (1998) Studies of lead corrosion in acetic acid environments. Studies in Conservation,... 

Test C The used oil lead content analyzed after 32,186 km run from a diesel engine, shown in Table 6.7, indicates that the lead corrosion rate is highest for the magnesium sulfonate containing oil. 

The quality of zinc deposit depends on the purity of the electrolyte. With a pure electrolyte, it is possible to use higher temperatures, and thereby lower electrolyte resistance and decrease electrode overvoltages. With an impure electrolyte, the temperature must be lowered to 30-35 °C to hinder hydrogen evolution caused by the impurities. Temperatures below 30 °C can cause formation of calcium sulfate temperatures above 40 °C can increase lead corrosion, and above 45 °C can increase sticking of the deposit. 

Lead Corrosion in plumbing, paints applied pre 1973, storage batteries... 

Although water decomposition and elemental-lead corrosion reactions are strongly inhibited by the low hydrogen exchange current on lead, overcharge without proper controls may result in severe damage due to the excessive gassing (see below). 

In addition to cleanliness, dispersants affect seal compatibility and copper/lead corrosion in engine oil formulations. 

U.S. 5624892 (1997) [128] Angevaare et al. (Lever Bros.) Aluminum sequestrant Inhibits lead corrosion... 

Negative health effects can result from corrosion of lead, corrosion of copper alloys and solder in water supply systems, and corrosion of copper plumbing in potable water systems. 

The effects of aUojring additives have been evaluated by adding Ag (an additive which reduces the rate of lead corrosion, ic) or As (an additive which increases the corrosion rate). The above additives have been introduced either as components to the lead alloy or as additives to the solution, maintaining their constant concentration by periodically introducing additional amounts of the additive. 

The traditional anodes for base metal electrowinning from sulfate solutions have been lead alloys containing calcium-tin, silver, or similar combinations. One potential concern with the lead anodes is the incorporation of lead corrosion products lowering the cathode purity. 

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