Ammonium ammonia

When chlorine is passed into aqueous ammonia, ammonium chloride and nitrogen are formed. If, however, sodium chloratefi) (hypochlorite) is used instead of chlorine, chloramine is first formed ... 

Recovery of Ammonia. The filter Hquor contains unreacted sodium chloride and substantially all the ammonia with which the brine was originally saturated. The ammonia may be fixed or free. Fixed ammonia (ammonium chloride [12125-02-97]) corresponds stoichiometrically to the precipitated sodium bicarbonate. Free ammonia includes salts such as ammonium hydroxide, bicarbonate, and carbonate, and the several possible carbon—ammonia compounds that decompose at moderate temperatures. A sulfide solution may be added to the filter Hquor for corrosion protection. The sulfide is distilled for eventual absorption by the brine in the absorber. As the filter Hquor enters the distiller, it is preheated by indirect contact with departing gases. The warmed Hquor enters the main coke, tile, or bubble cap-fiUed sections of the distiller where heat decomposes the free ammonium compounds and steam strips the ammonia and carbon dioxide from the solution. 

Fig. 6. World trends ia types of nitrogenous fertilizers consumed, where (—) represents anhydrous ammonia, ammonium phosphates, cogranulated...

Several zinc and copper micronuttient compounds are soluble in a variety of nitrogen solutions. Ammonia—ammonium nitrate solutions containing 2.5% Zn and 1% Cu can be prepared (100). Micronutrients are not very soluble in urea—ammonium nitrate solution unless the pH is raised to 7 or 8 by adding ammonia, whereupon zinc and copper become much more soluble. 

S. cerevisiae is produced by fed-batch processes in which molasses supplemented with sources of nitrogen and phosphoms, such as ammonia, ammonium sulfate, ammonium phosphate, and phosphoric acid, are fed incrementally to meet nutritional requirements of the yeast during growth. Large (150 to 300 m ) total volume aerated fermentors provided with internal coils for cooling water are employed in these processes (5). Substrates and nutrients ate sterilized in a heat exchanger and then fed to a cleaned—sanitized fermentor to minimize contamination problems. 

Petrochemicals are those chemicals produced from petroleum or natural gas and can be generally divided into three groups (/) aliphatics, such as butane and butene (2) cycloaliphatics, such as cyclohexane, cyclohexane derivatives, and aromatics (eg, ben2ene, toluene, xylene, and naphthalene) and (J) inorganics, such as sulfur, ammonia, ammonium sulfate, ammonium nitrate, and nitric acid. 

For binder preparation, dilute hydrochloric or acetic acids are preferred, because these faciUtate formation of stable silanol condensation products. When more complete condensation or gelation is preferred, a wider range of catalysts, including moderately basic ones, is employed. These materials, which are often called hardeners or accelerators, include aqueous ammonia, ammonium carbonate, triethanolamine, calcium hydroxide, magnesium oxide, dicyclohexylamine, alcohoHc ammonium acetate, and tributyltin oxide (11,12). 

At approximately 160°C, some of the ammonium thiocyanate is converted to thiourea [62-56-6] H2NCSNH2, iulow yield. With alcohoHc ammonia, ammonium dithiocarbamate [513-74-6] forms ... 

Reactions of ammonia and amines with carboxyUc acids result in the formation of a variety of products (47,48). Ammonium salts, RCOONH, are prepared with or without solvent, by reaction with anhydrous ammonia. Ammonium salts readily decompose to acid ammonium salts,... 

Zinc oxide [1314-13-2] (mol wt 81.37 Cl Pigment White 4, Cl No. 77947) is a white or yellowish white amorphous, odorless powder with pH 6.95—7.37. It is practically iasoluble in water but soluble in dilute acetic acid, mineral acids, ammonia, ammonium carbonate, and alkaU hydroxides. 

Alkali and alkaline earth metals, e.g. sodium, potassium lithium, magnesium, calcium, powdered aluminium Anhydrous ammonia Ammonium nitrate... 

Treatment of ammoniabearing waste from chemical industry Liberation of gaseous ammonia Ammonium chloride Nitric acid... 

Azninon, m. ammonia. — oxalsauer oxalate of ammonia, ammonium oxalate. 

Atz-ammoniak, n. caustic ammonia (ammonium hydroxide), ammonia water. artikel, m. (Calico) discharge style. bad, n. etching bath. 

S< dium Aluminato. . Ammonium Alum. . rola.uium Alum. . . Ammonia. . Ammonium (Ion). . Ammonium Chloride Ammonium Hydroxide Ammonium Sulfale... 

Fig. 13.1 Log/log plot of gold-plate porosity against thickness for the conventional hot-cyanide gold-plating bath on copper substrate. The porosity was determined by the amount of copper (p.p.m.) dissolved under standard conditions by an ammonia-ammonium persulphate...

This is the basis of the indicator action in the EDTA titration. The pH of 10 is attained by the use of an aqueous ammonia-ammonium chloride buffer mixture. 

Procedure. Prepare an ammonia-ammonium chloride buffer solution (pH 10), by adding 142 mL concentrated ammonia solution (sp. gr. 0.88-0.90) to 17.5 g ammonium chloride and diluting to 250 mL with de-ionised water. 

Silver halides can be dissolved in a solution of potassium tetracyanonickelate(II) in the presence of an ammonia-ammonium chloride buffer, and the nickel ion set free may be titrated with standard EDTA using murexide as indicator. 

The monoethanolamine-hydrochloric acid buffer has a buffering capacity equal to the ammonia-ammonium chloride buffer commonly employed for the titration of calcium and magnesium with EDTA and solochrome black (compare Section 10.54). The buffer has excellent keeping qualities, sharp end points are obtainable, and the strong ammonia solution is completely eliminated. 

The procedure involved in the determination of these anions is virtually that discussed in Section 10.58 for the indirect determination of silver. The anion to be determined is precipitated as the silver salt the precipitate is collected and dissolved in a solution of potassium tetracyanonickelate(II) in the presence of an ammonia/ammonium chloride buffer. Nickel ions are liberated and titrated with standard EDTA solution using murexide as indicator ... 

Procedure. Prepare a standard (0.05M) solution of magnesium sulphate or chloride from pure magnesium (Section 10.60), an ammonia-ammonium chloride buffer solution (pH 10) (Section 10.54), and a standard (0.05M) solution of EDTA. 

An immediate application of the use of the aqueous ammonia-ammonium chloride mixture may be made to the familiar example of the prevention of precipitation of magnesium hydroxide (S.P. 1.5 x 0-11). We can first calculate the minimum hydroxide ion concentration necessary to prevent precipitation in, say, 0.1M magnesium solution. 

Reagents. In view of the sensitivity of the method, the reagents employed for preparing the ground solutions must be very pure, and the water used should be re-distilled in an all-glass, or better, an all-silica apparatus the traces of organic material sometimes encountered in demineralised water (Section 3.17) make such water unsuitable for this technique unless it is distilled. The common supporting electrolytes include potassium chloride, sodium acetate-acetic acid buffer solutions, ammonia-ammonium chloride buffer solutions, hydrochloric acid and potassium nitrate. 

The same expression can be used for a basic buffer, with pKa that of the conjugate acid of the base (for example, in the case of an ammonia buffer, we would use the pKa of NH4+). If only pKb is available, calculate pKa by using Eq. 1 lb of Chapter 10 (pKa + pKb = pfCw). For example, for an ammonia/ammonium buffer we would write... 

Fig. 12-5 The ammonia-ammonium cycle. Each arrow represents one flux. The magnitude of the flux is given in Tg N/yr Where two numbers are given, the top value is the anthropogenic contribution and the lower is the total flux (natural + anthropogenic).

Whether nitrogen is in the reduced form (ammonia, ammonium salts, hydrazine) or the oxidised form (nitrites, nitrates), sodium gives rise to dangerous interactions. With the first set of compounds metalation occurs with formation of unstable or highly reducing compounds, whilst, with the second, redox reactions occur. 

Laterite Reduction roasting 2 NiO + C —> 2 Ni + C02 Ammonia-ammonium carbonate leaching in the presence of oxygen... 

Ammonia, Ammonium nitrate, Diphenyl carbonate Buzard, J. et al., J. Amer. Chem. Soc., 1952, 74, 2925-2926 During the synthesis of 15N-labelled urea by interaction of labelled ammonium nitrate, liquid ammonia and diphenyl carbonate in presence of copper powder, a series of explosions of the refrigerated sealed tubes was encountered. This was almost certainly caused by condensation of traces of oxygen in the tubes cooled to — 196°C dining condensation of ammonia before sealing the tubes. Cooling to —80°C would have been adequate and have avoided the hazard. 

The resulting calcine is leached with an ammonia/ammonium carbonate solution,... 

When carbon dioxide is passed into a nearly saturated solution of sodium chloride containing some ammonia, ammonium bicarbonate is formed. The heart of the process is the exploitation of the equilibrium between this bicarbonate and sodium and ammonium chlorides NH4HC03 + NaCl NaHC03 + NH4C1... 

Dissolve the sample in nitric acid. Separate Pb by extraction with CHC solution of sodium diethyl dithiocarbonate using alkaline cyanide solution to mask interferences. Titrate Pb in an ammonia-ammonium chloride medium at pH =10 using eriochrome black T. 

SAQ 6.13 What is the pH of ammonia-ammonium buffer if three volumes of NH4CI are added to two volumes of NH3 ... 

SAQ 6.14 Consider the ammonia-ammonium buffer in Worked Example 6.12. Starting with 1 dm3 of buffer solution containing 0.05 mol dm-3 each of NH3 and NH4CI, calculate the pH after adding 8 cm3 of NaOH solution of concentration 0.1 mol dm 3. 

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