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Aluminum
Published in Brian D. Fath, Sven E. Jørgensen, Megan Cole, Managing Global Resources and Universal Processes, 2020
Bernhard Wehr Johannes, Cardell Blamey Frederick Paxton, Martin Kopittke Peter, William Menzies Neal
Due to its corrosion resistance, light weight, and excellent thermal and electrical conductivity, the metal is extensively used in the building and construction industries (window frames, doors, external cladding, A/C ducts, thermal insulation), automotive (engine blocks, car bodies), shipping (hulls) and aerospace industries (aircraft bodies), power lines, and food packaging (cans and other containers, foil). Aluminum salts and compounds are used for water purification, in which alum (KAl(SO4)2.12H2O) is important, as catalysts in the chemical industry, and as ingredients in cosmetics (antiperspirants), pharmaceuticals (antacids, vaccine adjuvant), and foods (baking powder, spreading agent) (Table 1).
Downstream Processing
Published in Debabrata Das, Debayan Das, Biochemical Engineering, 2019
Alum is a common coagulation compound used in the chemical and biochemical industries. Chemically, alum is represented as aluminum potassium sulfate, K2SO4·Al2(SO4)3·24H2O. Fine particulates are agglomerated to clump together into a floc, which is known as the flocculation process. In other words, the flocculation process can be described as one where the negatively charged particulates accumulate around the positively charged flocculent. Due to large size, the floc may settle on the bottom of the liquid in the sedimentation process. The floc may float to the top of the liquid (known as creaming) or can also be filtered easily. Chitosan acts as a flocculent in the microalgae-harvesting process. By increasing or decreasing the pH of the cell mass suspension, it is possible to separate the cells, e.g., microalgae. Filter aids consist of solid particles (e.g., diatomaceous earth) that improve filtering efficiency.
Water Pollution
Published in Frank R. Spellman, The Drinking Water Handbook, 2017
If we were to take the time to hold a full glass of water and inspect the contents, we might find that the contents appear cloudy or colored, making us think that the water is not fit to drink. Or, the contents might look fine but an odor of chlorine is prevalent. Most often, though, we simply draw water from the tap and either drink it or use it to cook dinner. The fact is that typically a glass of treated water is a chemical cocktail (Kay, 1996). Water utilities in communities seek to protect the public health by treating raw water with certain chemicals; what they are in essence doing is providing a drinking water product that is a mixture of various treatment chemicals and their byproducts. Water treatment facilities typically add chlorine to disinfect, but chlorine can produce contaminants. Another concoction is formed when ammonia is added for disinfection. Alum and polymers are added to the water to settle out various contaminants. The water distribution system and appurtenances must be protected from pipe corrosion, so the water treatment facility adds caustic soda, ferric chloride, and lime, which in turn increase the aluminum, sulfates, and salts in the water. Thus, when we hold that glass of water before us and we perceive a full glass of crystal clear, refreshing water, what we are really seeing is a concoction of many chemicals mixed with water, forming the chemical cocktail. The most common chemical additives used in water treatment are fluorides, chlorine, and flocculants. Because fluorides have already been discussed, the discussion in the following sections focuses on the byproducts of chlorine and flocculant additives.
Alum efficacy 11 years following treatment: phosphorus and macroinvertebrates
Published in Lake and Reservoir Management, 2018
Alan D. Steinman, Michael C. Hassett, Maggie Oudsema, Richard Rediske
Although many sediment management technologies exist to deal with internal loading, one of the most common practices is chemical treatment (Cooke et al. 2005). Chemical applications are intended to bind the P, and usually include aluminum sulfate (alum), lime, or iron (Cooke et al. 2005, Bakker et al. 2015), although lanthanum-modified bentonite (Phoslock) is gaining acceptance, especially outside of the United States (Robb et al. 2003, Spears et al. 2013, 2016; Epe et al. 2017). Alum is particularly effective due to its dual mode of action for P removal. Alum reacts with soluble P to form an insoluble precipitate (Stumm and Morgan 1996). In addition, alum will form an insoluble aluminum hydroxide floc at pH 6–8, which has a high capacity to adsorb large amounts of inorganic P (Kennedy and Cooke 1982). By these 2 mechanisms, an alum application can bind P and inhibit diffusive flux from sediments.
The mineral alum: an effective and low-cost heterogeneous catalyst for the successful synthesis of 5-substituted-1H-tetrazoles
Published in Inorganic and Nano-Metal Chemistry, 2021
Azam Karimian, Nahid Emarloo, Samira Salari
Based on the previously mentioned details and also in the continuation of our research program on the successful synthesis of heterocyclic compounds,[43–-47] we presently decide to report the mineral alum nanoparticles (NPs) as a new, green, and natural heterogeneous catalyst with significant catalytic. The alum is a white, porous, and crystalline double solid. That is inexpensive, safe, nontoxic, and readily available. Recently, mineral alum was also used for fluoride adsorption from aqueous samples.[48]