Solution of Alum

P perApplications. In beater additions, the latex is mixed with the beaten paper pulp either by addition at the beater or to the stock chest at the wet end of the paper machine. In either case, the pH of the pulp is reduced to 4.0—4.5, usually by the addition of a solution of alum to the pulp—latex mixture which has been thoroughly agitated. The latex, which for this appHcation must be based on an anionic emulsifier, coagulates as the pH drops. The latex soHds separate ia intimate associatioa with the pulp fibers. The pulp is thea screeaed and the paper web formed ia the coaveatioaal way. A latex for this purpose must possess the proper balance between mechanical and chemical stabiHty. 

As previously stated, Wohler was unable to obtain metallic aluminum by Oersted s method. However, since the latter encouraged him to continue his attempts, he prepared some anhydrous aluminum chloride by Oersted s method, and devised a new plan for isolating the metal. After adding an excess of hot potassium carbonate solution to a boiling hot solution of alum, he washed and dried the precipitated aluminum hy-... 

Aluminium Niobate, A120 3.3Nb205.12HaO, is obtained as a white precipitate by the action of a solution of alum on sodium metaniobate, Na20. Nb205.7H20.2... 

Another tanning method is mineral tanning, which involves soaking a skin in a solution of alum and salt. This is called tawing. The products of this process are white and open-pored, and become stiff and hard when dried. Due to its open-pored texture, tawed leather is often treated with additives that fill in some of the irregularities and add to the skin s strength. Historically, these fillers have included flour, grease, egg yolks, and fat. 

The Romans first treated wood for fire retar-dancy in the first century a.d. They used solutions of alum and vinegar to protect their boats against fire. In 1820, Gay-Lussac advocated the use of ammonium phosphates and borax for treating cellulosic material. Many of the promising inorganic chemicals used today were identified between 1800 and 1870. Since then, the development of fire retardants for wood has accelerated. Commercially treated wood became available after the U.S. Navy (1895) specified its use in ship construction, and New York City (1899) required its use in buildings over 12 stories tall. Production reached over 65 million board feet in 1943, but by 1964 only 32 million board feet was treated annually.35... 

Aluminium ferrocyanide, Al4[Fe(CN)6]3.17H20, is formed when solutions of alum and potassium ferrocyanide are mixed in the cold,5 the alum being (presumably) in excess6 otherwise the double aluminium ammonium salt is produced. 

Precipitate aluminium hydroxide by adding ammonium hydroxide to a solution of alum. Wash the precipitate free from acid, and add a slight excess of concentrated hydrochloric acid. 

During the periods of ancient civilization, there was also some concern for prevention of fire and for flameproofing. It is known that the Egyptians soaked wood in a solution of alum, and that later, the Romans attempted to flameproof their houses and war vessels by dipping the wood in a bath of vinegar and clay. ... 

Aluminium Chromate.—The normal salt is not knowm. Aluminium hj droxide is soluble in chromic acid solutions, but the nature of the mixture varies with the temperature and the concentration of the chromic acid solution. A yellow floceulent precipitate of a basic aluminium chromate, AljO3.CrO3.7H2O, is produced by adding potassium chromate to a solution of alum. 

At ordinary temperature and pressure, the solution of alum or of sodium sulphate with the molecules of water in an aqueous solution almost saturated with the same salt is accompanied by a covilmcticn of the system in the same conditions, the solution of ammonium chloride is accompanied by an exparman. 

The first case is illustrated, as w e have said, by alum and sodium sulphate with ten molecules of water if we compress very slowly, in a piezometer, a saturated solution of alum or of sodium sulphate with ten molecules of water, in the presence of an excess of the same salt, the solution will dissolve a new quantity of salt it will remidn clear during the compression relieved cautiously and brought back to ordinary pressure, it will possess the properties... 

Alizarin was formerly dyed on wool mordanted wnth aluminium or chromium. I he aluminium mordant was deposited by immersing the goods in a 6 to 10 per cent solution of alum, to which 5 to 8 per cent of potassium hydrogen tartrate had been added. Fhe wool was entered into the cold... 

Aluminium acetate, known as red liquor, or mordant rouge, is used in dyeing for the production of red colour. One method of preparation is to add a solution of alum to acetate of lime liquor. The lime is precipitated as sulphate, its place being taken by the aluminium forming the acetate. 

Write or draw with a weak solution of alum in lemon juice. The characters or drawing will be invisible untU wetted with water, which wiU render them of a greyish colour, and quite transparent. On a letter, written with a wehk solution of rock-alum alone, being dried, and having a small quantity of water poured over it, the writing will appear of a whiter colour than the paper. 

An Italian chemist named Sementini found a strong solution of alum applied to the skin rendered that part (temporarily), very unsusceptible to fire, in other words a red hot iron could be applied for a short time with impunity. Soap impregnated with alum and... 

Compound Solution of Alum. Rub together 1 ounce each alum and sulphate of zinc dissolve iu 3 pints boiling water. If necessary, filter. This is detergent and astringent, and is used as a lotion for old ulcers, excoriations < c. and, largely diluted with water, as an ere-wash and injection. 

Alum Injection for Leucor-rhoea. Compound solution of alum, 6 drachms water, 1 quart. Mix, and use it lukewarm. 

Saturated solution of alum, carbouato of soda, and sulphate of zinc boils. 

Aluminum hydroxide forms a very gelatinous precipitate, as is evident if a dilute solution of alum in a test tube is neutralized by NaOH a milligram or so of precipitated A1(0H)3 will fill the whole tube. Because of this property, the precipitate settles very slowly, and as it does so, it travels down with the fine particles in the treated water. Secondary settling is thus an integral part of the coagulation treatment. 

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. 

Pure alumina is best prepared as follows —solution of alum is precipitated by an excess of chloride of barium, by which means the sulphuric acid is separated, and chloride of aluminum is left in solution with the chloride of potassium and the excess of chloride of barium. Alum (KOjSOj-f ALO, 3SO3) with 4BaCl yields 4(Ba0,S03)+KCl+Al3Cl On evaporation, water is decomposed, and hydrochlorate of alumina is formed, Al3Cl3+3H0=Al303j3HCl. When the dry mass is ignited, the hydrochloric acid is expelled, and the alumina is left with the chlorides of potassium and barium, which are removed by water. 

Besides the. use of alumina in pottery, it is much used in dyeing and calico printing, from its attraction for vegetable colouring matters, and for the fibre of cloth. It forms a bond of union between the cloth and the dye, and fixes the latter on the former. It is said, in this, to act as a mordant, and is most generally used in the shape of alum or acetate of alumina. When solution of alum is mixed with a colouring matter, and... 

The First Elixir is called Flower of Cinnabar. First ma e the Mysterious and Yellow. With an aqueous solution of realgar, an aqueous solution of alum, Tur estan salt, la e salt, arsenolite, oyster shells, red clay, talc, and white lead—several dozen ounces of each—ma e the Mud of the Six-and-One. (Baopu zi, 4.74)... 

Add a little bit of alum to the water and stir it in. Try to do this before the water cools down too much. As you ll recall, we can expect the alum to be more soluble at higher temperatures. We want to create a saturated solution of alum, but we also want to make sure that all of it dissolves. Continue adding alum until it will not dissolve anymore, and then you can add a little bit more hot water to get the last bit of alum to dissolve. 

If crystals should not form upon cooling the solution of alum, why is an additional 10. mL of water evaporated from the solution ... 

Typical use is for manufacture of alum from dilute solution of alum. 

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