Aluminum precipitates

Lead alloys containing 0.09—0.15 wt % calcium and 0.015—0.03 wt % aluminum are used for the negative battery grids of virtually all lead—acid batteries in the United States and are also used in Japan, Canada, and Europe. If the molten alloy is held at too low a temperature, the aluminum precipitates from solution, rises to the surface of the molten alloy as finely divided aluminum particles, and enters the dross layer atop the melt. 

Munk, L. Faure, G. Pride, D., Bigham, J. 2002. Sorption of trace metals to an aluminum precipitate in a stream receiving acid rock-drainage Snake River, Summit County, Colorado. Applied Geochemistry, 17, 421-430. 

Aluminum precipitate caused problems in SCWO reactor and downstream components... 

Iron and aluminum precipitate out when treated with ammonia and are removed by filtration. Other metals, such as copper, zinc, lead and arsenic are precipitated and removed as sulfides upon passing hydrogen sufide through the solution. Colloidal particles of metaUic sulfides and sulfur are removed by treatment with iron(ll) sulfide. The purified solution of manganese(ll) sulfate is then electrolyzed in an electrolytic cell using lead anode and HasteUoy or Type 316 stainless steel cathode, both of which are resistant to acid. Manganese is deposited on the cathode as a thin film. 

The anion is irrelevant for the catalysis. However, it participates in the reaction by producing ester. This fact confirms the correctness of the proposed reaction mechanism under discussion. If, for instance, w-butyl benzoate reacts with 2-ethylhexanol in the presence of a large quantity of basic aluminum stearate, distinctly detectable quantities of 2-ethylhexyl stearate can be found in the reaction product, and an equivalent amount of benzoic acid is found in the filtered aluminum precipitate. 

Violante, A., Ricciardella, M., Del Gaudio, S. and Pigna, M. (2006) Coprecipitation of arsenate with metal oxides nature, mineralogy, and reactivity of aluminum precipitates. Environmental Science and Technology, 40(16), 4961-67. 

Yu, G., Saha, U. K., Kozak, L. M., and Huang, P. M. (2006). Kinetics of cadmium adsorption on aluminum precipitation products formed under the influence of tannate. Geochim. Cosmochim. Acta 70,5134-5145. 

Aluminum is present in many primary minerals. The weathering of these primary minerals over time results in the deposition of sedimentary clay minerals, such as the aluminosilicates kaolinite and montmorillonite. The weathering of soil results in the more rapid release of silicon, and aluminum precipitates as hydrated aluminum oxides such as gibbsite and boehmite, which are constituents of bauxites and laterites (Bodek et al. 1988). Aluminum is found in the soil complexed with other electron rich species such as fluoride, sulfate, and phosphate. 

Aluminum precipitation system Aluminum precipitation Unspecified TSDF (not contaminated by agent)... 

Both nickel and aluminum precipitate hydrous oxide sols. For best combinations, care must be taken to ensure that precipitation occurs simultaneously. Variations of pH within the vessel or during addition of the alkali result in preferential precipitation of one component, yielding product nonuniformity. One laboratory approach is to use the apparatus shown in Fig. 6.I1. ... 

Table III. Comparison of Aluminum Precipitation from iso-pH Solutions...

Shang, C., Caldwell, D.E., Stewart, J.W.B., Tiessen, H. and Huang, P.M. (1995) Bioavailability of organic and inorganic phosphates adsorbed on short-range ordered aluminum precipitate. Microbial Ecology 31,2 9-3 9. 

Violante, A., Huang, P.M., 1992. Effect of tartaric acid and pH on the nature and physicochemical properties of short-range ordered aluminum precipitation products. Clays Clay Miner. 40,462-469. 

Separates Fe and A1 from Be by electrolysis in ammo nium oxalate solution. Iron reduced. Aluminum precipitated by use of stronger current, as hydroxide by ammonium carbonate produced and beryllium left in solution. 

Aluminum precipitates as the hydroxide in near-neutral brine. It also combines with silica to form aluminum silicates and calcium aluminosilicates. 

AMAX researchers added an alkali to nickel laterite PAL slurry, primarily to improve settling properties [13], However it was noted that iron and aluminum precipitation occurs ... 

Commoii secondary minerals of iron and aluminum precipitating from AMD... 

Cheluviation. Cheluviation involves the transport of organo-metallic complexes (i.e., chelates) of iron and aluminum. Once transported to the lower horizon B, the iron and aluminum precipitate as iron and aluminum sesquioxides forming colored spodic horizons denoted B,. 

Kowalchuck, E.E. (2011) Selective fluoride removal by aluminum precipitation membrane filtration. Master s Thesis. University of New Mexico, Albuquerque, NM. Available from http //repository.unm.edu/handle/1928/17436 [accessed March 2014]. 

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