Ammonium phosphate, effect

Iron. As with copper, some dozen or more materials are used as fertilizer Hon sources. These include ferrous and ferric oxides and sulfides and ferrous ammonium phosphate [10101 -60-7] ferrous ammonium sulfate [10045-89-3] frits, and chelates. In many instances, organic chelates are more effective than inorganic materials. Recommended appHcation rates range widely according to both type of micronutrient used and crop. Quantities of Fe range from as low as 0.5 kg/hm as chelates for vegetables to as much as a few hundred kg/hm as ferrous sulfate for some grains. 

Effects on Visible Smoke. Smoke is a main impediment to egress from a burning building. Although some examples are known where specific phosphoms flame retardants increased smoke in small-scale tests, other instances are reported where the presence of the retardant reduced smoke. The effect appears to be a complex function of burning conditions and of other ingredients in the formulation (153,156,157). In a carehil Japanese study, ammonium phosphate raised or lowered the smoke from wood depending on pyrolysis temperature (158). Where the phosphoms flame retardant functions by char enhancement, lower smoke levels are likely to be observed. 

The most widely deployed industrial explosion suppressant is mono-ammonium phosphate powder (MAP). This suppressant has a wide range of effectiveness. However, it can prove to be a contaminant, necessitating stringent clean-down procedures after a suppressed explosion incident. This limitation is overcome by selecting a sodium... 

A basic scientific investigation of fire retardancy, however, remained to be initiated by Gay-Lussac in France at the request of King Louis XVIII in 1821 who was again interested in reducing the flammability of theater curtains. This researcher noted that the ammonium salts of sulfuric, hydrochloric and phosphoric acids were very effective fire retardants on hemp and linen and that the effect could be improved considerably by using mixtures of ammonium chloride, ammonium phosphate and borax. This work has withstood the test of time and remains valid to this day. Thus the basic elements of modern fire retardant chemistry had been defined early in recorded history and remained the state of the art until early in the twentieth century. The most effective treatments for cellulosic materials being concentrated in Groups III, V and VII elements. 

Figure 1. Effect of ammonium phosphate on penetrability (Darcy Constant) of char from novolak pyrolysis.

George, C. W., R. A. Susott. Effects of Ammonium Phosphate and Sulfate on the Pyrolysis and Combustion of Cellulose Forest Service Research Paper INT-90, U.S.D.A., 1971. 

At pH 7.0, ammonium phosphate buffer was found to give similar retention but somewhat improved peak shape as compared with potassium phosphate buffers, presumably because of the superior deactivating effect of the ammonium ion on ionized silanols [72], In contrast, this effect was hardly observed at low pH, probably... 

In the fourth type of fire retardants, a chemical bond between the molecules of the fire retardant and cellulose should produce a finish that strongly resists the effects of laundering and weathering. Among such retardants may be cited cellulose-ammonium phosphate, cellulose-urea phosphate, cellulose-titanium complexes cellulose-titanium-antimony finishes... 

All these materials produced intumescence to some degree, but only a few showed enough to be of real value. The most effective was a combination of paraformaldehyde, urea, and ammonium phosphate. This confirms the work of Jones and Soll(J.). The combination of isano oil with polyamide resin gave best results in exterior paint formulations. Amino acetic acid with starch and also with ammonium phosphate gave good results. 

Applicable to <20 mg 1, in natural and waste water. Ammonium phosphate must be added to mask interferences of residual ferric chloride. The effect of other interferents (reducing agents and thiosulfate) may be important. 

Effective glow retardants for wood are the ammonium phosphates, ammonium borates, boric acid, phosphoric acid, and compounds that yield phosphoric acid during pyrolysis (3,5). ... 

Asia dominates the world import market for urea and ammonium phosphates. China and India are particularly large importers and variations in their import requirements have a major impact on world prices. The agricultural and fertilizer sectors of these two countries could be affected by the World Trade Organization (WTO) agreements with China. The agreements will probably have a beneficial effect globally. However, some individual countries and companies may experience adverse effects36. 

Ammonium phosphates were first recommended for flame retarding theater curtains by Gay-Lussac in 1821. Mono- and diammonium phosphates, or mixtures of the two, are widely used to impart flame resistance to a wide variety of cellulosic materials such as paper, cotton, and wood.21 These salts have proven to be highly efficient at relatively low costs of application. They are also very effective in preventing afterglow. However, flame-retardant formulations based on these salts are generally nondurable, because they are water soluble and, therefore, are easily susceptible to leaching out from the material matrix. 

Interestingly enough, Schmittman et al. claimed that a combination of ammonium polyphosphate (APP), ammonium phosphate, borax, anhydrous borax (<45 pm), and melamine can be used in urethane panels to meet the German standard DIN 4102, Part 1, point 6.1.2. (B1 classification).13 They specifically reported that the combination of borax and anhydrous borax yields surprisingly effective results. 

Cotton Ammonium phosphates are the most effective FRs for cotton as first identified by Gay-Lussac in 1821 and still widely used. All phosphates on heating release phosphoric acid, which catalyses dehydration reactions of cellulose to yield char at the expense of volatiles formation reactions.50 However, ammonium phosphates like mono- or diammonium phosphates are water soluble, hence applicable as nondurable treatments only. Ammonium bromide can be used in combination with ammonium phosphates to provide some vapor-phase FR action. Other examples include borax and boric acid, ammonium sulfamate, and sulfates. These nondurable finishes are useful for disposable fabrics, insulation, wall boards, theatrical scenery, packaging material, paper, etc. Ammonium polyphosphates (APPs) are used in combination with urea to provide semidurable finishes and by curing at 160°C, when some phosphorylation can occur. Semidurable finishes are very useful for materials that may not need frequent washings, e.g., mattresses, drapes, upholstery, carpets, etc. Some commercial examples of semidurable finishes include Flammentin FMB (Thor Specialities), Pyrovatim PBS (Ciba, now marketed by Huntsman), etc.26... 

Fig. 24.14. Effect of NH3 H3P04 mole ratio on solubility of ammonium phosphate at 75°C. (Source Fertilizer Manual.)...

Other ammonium salts are used as fertilizers, and the first step in their production is the production of ammonia by the Flaber process. Some of the ammonium salts that are effective for use as fertilizers are ammonium sulfate and ammonium phosphate that are prepared by the reactions... 

FIGURE 5-27. Effect of column surface upon retention of organic amines ( ) separation on a fully coated C]8 column, (b) Separation on a column with 50% coating level of C18. (c) Separation on a column of silica. The mobile phase is acetonitrile/ water (60 40) with 4 mM dibasic ammonium phosphate (pH 7.8). The sample components are (1) benzocaine, (2) lidocaine, (3) etidocaine, and (4) tetracaine. (Reprinted from reference 4 with permission.)... 

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