Ammonium aluminum sulfate alum

The word alum is derived from the Latin alumen, which was appHed to several astringent substances, most of which contained aluminum sulfate (20). Unfortunately, the term alum is now used for several different materials. Papermakers alum or simply alum refers to commercial aluminum sulfate. Common alum or ordinary alum usually refers to potash alum which can be written in the form K SO Al2(SO 24H20, or it can refer to ammonium alum, ammonium aluminum sulfate. The term is also appHed to a whole series of crystallised double sulfates [M(l)M (lII)(SO 2 12H20] having the same crystal stmcture as the common alums, in which sodium and other univalent metals may replace the potassium or ammonium, and other metals may replace the alurninum. Even the sulfate radical may be replaced, by selenate, for example. Some examples of alums are cesium alum [7784-17-OJ,... 

Ammonium aluminum alum Ammonium aluminum sulfate. See Ammonium alum Ammonium amidosulfate. See Ammonium sulfamate... 

Alprostadil, IntracavOTiosal (Cavaject, Edex) Alprostadil, Urethral Suppository (Muse) Ammonium Aluminum Sulfate [Alum] BeUadonna Opium Suppositories (B O Supprettes)... 

There are a number of mineral and metallic salts which have a long association with the alchemical art. The fifteenth century alchemist, Isaac Holland describes The Hand of the Philosophers as being an assembly of important salts in alchemical works. These salts include Niter (potassium nitrate), Sal Ammoniac (ammonium chloride), Vitriol (copper or iron sulfate), Alum (potassium aluminum sulfate), and common salt (sodium chloride). 

The concept of fire-retardancy is remarkably old. The Greek historian, Herodotus, in 484-431 BC recorded that the Egyptians imparted fire-resistance to wood by soaking it in a solution of alum (potassium aluminum sulfate) [Browne, 1958]. The Romans added vinegar to the alum for the same purpose. Vitruvius in the first century BC described the natural fire-retardant properties of the larch tree and some military applications of fire retardant materials such as plaster of clay reinforced with hair [Vitruvius, I960]. In 1638, Circa recorded that Italian theaters were painted with a mixture of clay and gypsum (potassium aluminum silicate and hydrated calcium sulfate) to protect them from fire. Wild was issued a British patent in 1735 for his process of treating wood with a mixture of alum, ferrous sulfate and borax (sodium tetraborate decahydrate). And Gay-Lussac in 1821 showed that a solution of ammonium phosphate, ammonium chloride and borax acts as a fire-retardant for wood. 

Aluminum Sulfate (Alum). Alum, a double sulfate of potassium and aluminum having twelve waters of crystallization, KA1(S0 2 12H20, is the earliest referenced aluminum containing compound. It was mentioned by Herodotus in the fifth century BC. The Egyptians used alum as a mordant and as a medicine the Romans used it for fireproofing. Some alums contain sodium or ammonium ions in place of potassium. 

Aloton Also called Buchner. A process proposed for extracting aluminum from clay. Calcined clay is leached with ammonium hydrogen sulfate solution under pressure, and ammonium alum is crystallized from the liquor. Invented by M. Buchner in Hanover-Kleefeld in 1921 piloted in Germany in the 1920s and in Oregon in 1944. It was never commercialized, but provided the basis for the Nuvalon process which was. 

Beginning in the 1700s and beyond, scientists suspected that an unknown metal existed in alum. Alum is found in the form of several compounds—for example, aluminum ammonium sulfate [A1NH IS0 )j 12H20], aluminum potassium sulfate [AlK(SO )2 12HjO], or aluminum sulfate [Alj(SO ) j]. The scientists problem was that they had no techniques or knowledge of how to extract the metal from its ore until 1825 when the Danish chemist Hans Christian Oersted (1777-1851) isolated a very small amount of aluminum by melting alum with potas-... 

Synonyms alum, cake alum (the term alum also refers to aqueous solutions of this substance, as well as other hydrate salts containing varying number of waters of crystaUization also the term alum apphes to a whole class of sulfate double salts, such as potassium aluminum sulfate or ammonium aluminum... 

Two tilings about aluminum will interest you as a chemist. One is that aluminum is an "amphoteric element, which means that it can form not only a base (Al(OH)j). hut also an acid (HA 10,). The other is that aluminum sulfate (Al SO, ) has the ability to combine with potassium sulfate (K,SO ) and ammonium sulfate ((NHJjSO,) into beautiful cubic crystals of double salts called alums — KA1 (S04)3 12H,0 and NH4A1(S04),-12H,0. 

Alum Ammonium alums are those alums, such as aluminum ammonium sulfate A12(NH4)2 (804)4 24H20, ferric ammonium sulfate Fe2(NH4)2< S04)4 - 24H2O, chromium ammonium sulfate Cr2(NH4)2 (S04)4 24H2O where ammonium sulfate is crystallized with the heavier metal sulfate. 

DOUBLE SALT. A hydrated compound resulting from crystallization ol a mixture of ions in aqueous solution. Common examples arc the alums, made by ciystallizing from solution either potassium or ammonium sulfate and aluminum sulfate Rochelle salt (potassium sodium tartrate), made from a water solution of potassium acid tartrate treated with sodium carbonate and Mohr s salt (fertous ammonium sulfate), crystallized Iruin mixed solutions of ferrous sulfate and ammonium sulfate. 

Aloton Also called Buchner. A process proposed for extracting aluminum from clay. Calcined clay is leached with ammonium hydrogen sulfate solution under pressure, and ammonium alum is... 

Bauxite aluminum oxide (alumina, corundum, emery, ruby, sapphire) aluminum sulfate alum ammonium alum. Aluminum chloride aluminum acetate. Uses of aluminum compounds. 

Aluminum sulfate is manufactured by the reaction of aluminum hydroxide or other aluminum raw materials, such as bauxite or kaolin, with sulfuric acid at ca. 170°C in a pressure-resistant agitator vessel. The melt obtained after concentration contains ca. 57% aluminum sulfate (ca. 13 moles of crystallization water). Double salts of aluminum sulfate with potassium, ammonium or sodium sulfate (alums e.g. potassium alum KA1(S04)2 12H2O) have been largely supplanted by aluminum sulfate. 

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