Uses of Ammonium Phosphates

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... 

The use of ammonium phosphates or phosphoric acid for adjustment of the pH value of the dyebaths has been recommended (E. I. Noble, Textile J. of Australia, 1944, 19, 71). It is claimed that, because of the buffering action of phosphates, phosphoric acid neutralizes variations in alkalinity remaining after scouring, more effectively than do other acids. Scoured wool is usually alkaline and, with dyes other than the most levelling, it is extremely important that the acid in the dyebath should bring the whole of the load to a state of uniform pH value before any adsorption of dye takes... 

In the period 1965-75, TSP sipplied approximately 15%r20% of the fertilizer phosphate used worldwide. This declined to 13.3% in 1988 and to 10.7% in 1992, primarily as a result of a continuous increase in the use of ammonium phosphates, mainly diammonium phosphate (DAP). 

It is obvious that the added ammonia is used up. No changes in the composition of the wine were noted. He recommends use of ammonium phosphate for cold musts. 

Formulations of ammonium phosphates and ammonium bromide are sold for use on ceUulosic—synthetic fiber blends. Other ammonium phosphate formulations contain wetting and softening agents. A large-volume, ca 9000 t/yr ia 1991, use ia the United States (48) for ammonium phosphate is ia forest fire control, usuaUy by aerial appUcation (see also Ammonium compounds). 

Ammonium chloride [12125-02-9], ammonium sulfate [7783-20-2], and diammonium phosphate [7708-28-0] have also been used for shale stabilization (102,103). Ammonium ions have essentially the same effect on shales as potassium ions but use of ammonium salts is often objectionable because of the alkaline nature of the mud. In the North Sea and northern Europe, where magnesium-bearing salt formations ate encountered, magnesium chloride [7786-30-3] is used, but in the United States it is used only on a small scale. 

Ammonium Phosphates. In the manufacture of ammonium phosphates, an atmosphere of ammonia may need to be maintained because the partial pressure of ammonia rises rapidly as either the temperature or the NH2/P20 mole ratio of the reaction mass increases. Phosphoric acid reacts quickly with ammonia vapor and is used in multistage reactor systems as a scmbber fluid to prevent NH emissions and recover ammonia values. For example, H PO scmbbing of coke-oven off-gases produces ammonium phosphates of relatively good purity. 

Ammonia is consumed in the manufacture of ammonium phosphates and ammonium sulfate by reaction with phosphoric acid and sulfuric acid, respectively. The phosphates may contain ortho- and polyphosphate values. Ammonium sulfate is also a by-product from other ammonia-using industries such as caprolactam (qv) and hydrogen cyanide (see Cyanides). 

Pla.tinum, Platinum plating has found appHcation in the production of platinised titanium, niobium, or tantalum anodes which are used as insoluble anodes in many other plating solutions (see Metalanodes). Plating solutions were often based on platinum "P" salt, which is diamminedinitroplatiniim (IT). A dinitroplatinite sulfate—sulfuric acid bath has been used to plate direcdy onto titanium (129). This bath contains 5 g/L of the platinum salt, pH adjusted to 2.0 with sulfuric acid. The bath is operated at 40°C at 10—100 A/m. Other baths based on chloroplatinic acid have been used in both acid and alkaline formulations the acid bath uses 20 g/L of the platinum salt and 300 g/L hydrochloric acid at 65° C and 10—200 A/m. The alkaline bath uses 10 g/L of the platinum salt, 60 g/L of ammonium phosphate and ammonium hydroxide to give a pH of 2.5—9.0. The alkaline bath can be plated directly onto nickel-base alloys acid baths require a gold strike on most metals. 

Magnesium may be precipitated from solution as MgNH4P04.6H20, a compound which has been widely used as a basis for the gravimetric determination of the element over many years. An examination of its use will serve to illustrate some of the problems associated with inorganic precipitations. The initial precipitation is made from a solution at pH = 11-12 by the addition of ammonium phosphate in excess. 

There has been a trend toward the production of ammonium phosphates in powder form, Concentrated phosphoric acid is neutralized under pressure, and the heat of neutralization is used to remove the water in a spray tower. The powdered product then is collected at the bottom of the tower. Ammonium nitrate/ammonium phosphate combination products can be obtained either by neutralizing mixed nitric acid and phosphoric acid, or by the addition of ammonium phosphate to an ammonium nitrate melt. 

Some chemical modifiers behave in other ways—they decrease analyte volatility or concomitant volatility—so that concomitants (matrix) are volatilized during the cleaning step. Examples of the first behavior are certain organic acids, such as ascorbic or citric acids, which react with volatile elements, thereby diminishing their volatilities. An example of the second type of behavior is the use of ammonium molybdate, which reacts with phosphate ions to form the highly refractory ammonium molybdophosphate. 

In shake-flask cultures, pH control is usually limited to either addition of buffering salts such as phosphates, or periodic manual pH adjustment, which is obviously tedious and less effective. The use of ammonium sulfate as the major nitrogen source in Mandels medium (10) requires a more compelling buffering system. Without buffering, the pH drops quickly... 

Ammonium phosphate can be used as a fertilizer. 6.0 g of ammonium phosphate is dissolved in sufficient water to produce 300 mL of solution. What are the concentrations (in mol/L) of the ammonium ions and phosphate ions present ... 

The trivalent orthophosphate anion (PO/ ) readily forms double salts, so that the number of reactants available is very large. Studies have included the decompositions of many acid salts, and acid salts may also be generated during decomposition of ammonium salts following the release of ammonia gas. Comparisons between the decomposition behaviour of related compounds (e.g. metal and acid salts) can yield useful mechanistic information. Removal of water often yields pyrophosphates or metaphosphates. Some higher molecular mass substances form glassy phases and these crystallize only with difficulty. The decompositions of ammonium phosphates are considered in Chapter 15. 

Reduction of the BOD is desirable, particularly for waste streams where the loading is 3-4 kg/tonne of pulp, or more. In concentration terms, BODs of 75-300 ppm (mg Oi/L) are common in kraft pulping effluents [39]. Biochemical waste treatment in activated sludge plants or artificially aerated waste lagoons, after adjustment of the water conditions to a pH in the 6.5-9 range, the temperature to 12-32°C, and addition of ammonium phosphate to provide nitrogen and phosphorus nutrients, accomplishes accelerated BOD reduction. Many of the bacteria, which are involved in this process have recently been isolated and identified [54]. Use of oxygen, rather than air, for... 

A further refinement which is now commonly used is to commence dyeing with 2 to 5 per cent of ammonium phosphate, or an ammonium hydrogen phosphate, so that the liberation of phosphoric acid shall be gradual. 

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