Ammonium sulfate solutions

Essentially all the ammonium sulfate fertilizer used in the United States is by-product material. By-product from the acid scmbbing of coke oven gas is one source. A larger source is as by-product ammonium sulfate solution from the production of caprolactam (qv) and acrylonitrile, (qv) which are synthetic fiber intermediates. A third but lesser source is from the ammoniation of spent sulfuric acid from other processes. In the recovery of by-product crystals from each of these sources, the crystallization usually is carried out in steam-heated sa turator—crystallizers. Characteristically, crystallizer product is of a particle size about 90% finer than 16 mesh (ca 1 mm dia), which is too small for satisfactory dry blending with granular fertilizer materials. Crystals of this size are suitable, however, as a feed material to mixed fertilizer granulation plants, and this is the main fertilizer outlet for by-product ammonium sulfate. 

Some companies have used the Merseburg process to manufacture ammonium sulfate from gypsum, but the process is only economically attractive where sulfur is unavailable or very expensive (32), and is thus not used in the United States. Ammonium carbonate, formed by the reaction of ammonia and carbon dioxide in an aqueous medium, reacts with suspended, finely ground gypsum. Insoluble calcium carbonate and an ammonium sulfate solution are formed. 

Concentrations are controlled to yield a molten oxime product layer and a saturated (ca 40 wt %) ammonium sulfate solution ca 125% (theoretical) ammonium sulfate or 2.9 kg/kg caprolactam is produced as a result of side reactions in the hydroxylamine synthesis. 

Ammonium sulfate is produced as a caprolactam by-product from the petrochemical industry, as a coke by-product, and synthetically through reaction of ammonia with sulfuric acid. Only the third process is covered in our discussion. The reaction between anunonia and sulfuric acid produces an ammonium sulfate solution that is continuously circulated through an evaporator to thicken the solution and to produce ammonium sulfate crystals. The crystals are separated from the liquor in a centrifuge, and the liquor is returned to the evaporator. The crystals are fed either to a fluidized bed or to a rotary drum dryer and are screened before bagging or bulk loading. 

Blau-warme, /. (Metal.) blue heat, -wasser, n. eau celeste (cupric ammonium sulfate solution). -wassergas, n. blue water gas, blue gas. 

A typical NaY zeolite contains approximately 13 wt% Na20. To enhance activity and thermal and hydrothermal stability of NaY, the sodium level must be reduced. This is normally done by the ion exchanging of NaY with a medium containing rare earth cations and/ or hydrogen ions. Ammonium sulfate solutions are frequently employed as a source for hydrogen ions. 

S100 proteins (named because of their solubility in a 100% ammonium sulfate solution) constitute the largest family within the EF-hand Ca2+-binding proteins superfamily [1]. SI00 proteins are small, acidic proteins containing two distinct Ca2+-binding EF-hand structural motifs [2]. The C-terminal EF-hand contains the... 

The solution is stirred for an additional 2 hours and is then cooled to 15°. Fifty grams of chopped ice and 75 ml. of ice-cold saturated ammonium sulfate solution are cautiously added in sequence while the temperature is maintained below 25° during the dilution (Note 4). The contents of the beaker are transferred to a separatory funnel, and the peroxybenzoic acid solution is... 

Dilution of the methanesulfonic acid is exothermic. Since peroxybenzoic acid has an appreciable solubility in aqueous methanesulfonic acid, dilution and washing are conducted with minimal quantities of saturated ammonium sulfate solution. 

The SI70 supernatant (220 ml) was made to 40 % saturation with solid ammonium sulfate, stirred for 20 min, and then the precipitate was collected by centrifugation at 15,000 g for 15 min. The precipitate was suspended in small volume of buffer B-50 at pH 7.6 containing 20 mM HEPES/KOH, 0.1 mM EDTA, 1 mM dithiothreitol, 10 % (v/v) glycerol, and 50 mM potassium acetate. The 60 % saturated ammonium sulfate solution was prepared similarly. Protein concentrations for 0 - 40 % and 40 - 60 % ammonium sulfate fractions were 4.2 mg/ml and 4.7 mg/ml, respectively. 

Feather, A. M. Cole, P. M. The separation of cobalt from nickel ammonium sulfate solution by solvent extraction. Value Adding through Solvent Extraction, [Papers presented at ISEC 96], Melbourne, Mar. 19-23, 1996, 1, 511-516. 

After the chromium (II) chloride solution has been transferred to flask B, the flow of ammonia through the reaction vessel should be started. The ammonia delivery tube should approach but not dip below the liquid level in flask B. If tank ammonia is used, the tank should be opened carefully to avoid spattering of liquids by a sudden burst of gas. If ammonia is to be generated, the ammonium sulfate solution should be added carefully to the potassium hydroxide in flask C. It may be necessary to cool flask C with ice at first, then to warm the generator later in order to maintain a reasonably constant flow of ammonia. The use of tank ammonia avoids these problems. If zinc was used in the reduction, a precipitate of zinc hydroxide forms first and redissolves. The violet-blue solution stirred at 0° is saturated with ammonia, then a 2- to 3-g. sample of the platinum catalyst is added rapidly to flask B. A strong countercurrent of nitrogen is used to prevent entrance of air into the system when the catalyst is added. The reaction mixture is allowed to stir for one hour while the flask is cooled with ice. 

Arbiter Previously known as the Sherritt-Gordon ammonia process. A process for leaching copper from sulfide concentrates, using ammoniacal ammonium sulfate solution at 85°C and relying on air oxidation. Copper is produced from the leachate by solvent extraction and electrowinning. Sulfur is recovered as ammonium sulfate. Operated on a large scale by the Anaconda Copper Company in Montana from 1974 to 1979. See Sherritt-Gordan. 

Next, let s see how we can use molarity to calculate moles. How many moles of ammonium ions are in 0.100 L of a 0.20 M ammonium sulfate solution ... 

The acid solution is filtered without suction through glass wool into a 2-1. separatory funnel and extracted once with 500 cc. of ether, then three times with 250-cc. portions of the same solvent. The combined ether extracts are shaken out with three 150-cc. portions of 40 per cent ammonium sulfate solution and dried for twenty-four hours, preferably in a refrigerator, over 50 g. of anhydrous sodium sulfate. 

HNL enzyme solution (Codexis Inc, 2.5 mL) trimethylsilylcyanide (1.25 mL) saturated ammonium sulfate solution (2.5 mL) ethyl acetate (25 mL) nitrogen gas fume hood cyanide detector 50 mL flask magnetic stirrer. 

Lipid hydration in ammonium sulfate solution to form multilamellar vesicles... 

The observation that improved remote loading of ciprofloxacin could be achieved using ammonium sulfate solutions rather than sodium citrate buffers highlighted the need for further investigation and development of drug-loading methodologies. In this section, we examine an approach in... 

The mixture is allowed to warm up over 20 minutes and is poured into a 2-1. separatory funnel. The purplish solution is washed with a saturated ammonium sulfate solution (about 1.5 1.) containing ferrous ammonium sulfate until the rust-brown ferric color is no longer produced. The organic layer is dried over magnesium sulfate and concentrated, leaving a dark solid. Purification of the solid by high-vacuum short path distillation gives 127-142 g. (73-81%) of a pinkish or tan-colored product, b.p. 148-150° (0.15 mm.), m.p. 145-147°. It may be further purified by sublimation, or recrystallization from benzene-hexane, m.p. 148-149°. 

Saturated ammonium sulfate (enzyme grade) Dissolve 800 g of ammonium sulfate in 1 L of hot BBS. Filter the solution through Whatman no. 1 paper and cool to room temperature. Confirm that the pH of the solution is 8.0 with a strip of narrow-range pH paper. Cool the saturated ammonium sulfate solution and store at 4°C (see Note 2). 

Pipet 16 mL of the clarified serum or ascites into each of six clean 50-mL polycarbonate tubes. Add 16 mL of cold, saturated ammonium sulfate solution and stir gently with a pipet (see Note 6). 

Fig. 7.10 Solubility of Versatic 911 (O.SOmoldm ) in ammonium sulfate solution. (From Ref. 15.)... 

The solubility of Kelex 100 has been reported to be 4.4 (pH 0.5), 1.4 (pH 1.0), and 1.6 (pH 1.5)ppm, in tests employing 0.5moldm Kelex 100 in Solvesso 150 diluent for the extraction of copper from solutions containing about 30 g dm of metals (Cu, Ni, and Co) [21]. Furthermore, over several months no change in the Kelex concentration was found in pilot plant operations with a 0.5moldm Kelex solution [21]. At higher pH values (up to 9) Kelex solubility has been determined at < 1 ppm in ammonium sulfate solutions up to 300 g dm [22]. It would be expected that the amphoteric nature of Kelex would show increasing solubility at pH values above 7, and lower than about 1, similar to the variation in solubility of... 

For most reactions, one can use 1-2 mM acetyl phosphate and 1-2 international units of acetate kinase. The enzyme is usually supplied as a crystalhne suspension in 3 M ammonium sulfate, and 10 mM ammonium ion is inhibitory. Therefore, a useful practice is to snip off 0.5 cm from a disposable Eppendorf micropipette tip to facih-tate removal of 10-20 microliters of the crystalline suspension then spin down the enzyme in a 1.5 ml disposable conical plastic centrifuge tube, and remove the ammonium sulfate solution with a wick of twisted Kim-wipe. The enzyme precipitate can now be taken up directly into your working buffer. Note Acetate kinase is inactivated by cold exposure, but incubation with 10 M ATP or GTP reactivates the enzyme if warmed to room temperature for 5-10 min. 

To precipitate a protein, mix its solution either at RT or 4 °C with the required amount of saturated ammonium sulfate solution (consider the different concentration of (NH4)2S04 at RT and 4 °C). As an example, mix 6 vol. of protein solution with 4 vol. of saturated ammonium sulfate solution to get 40% saturation. 

Allow the precipitate to form overnight at the required temperature (do not store in a refrigerator if % saturation is made for room temperature). Spin with 2000 x g for 10 min, wash the pellet by suspending in ammonium sulfate solution of the indicated degree of saturation, spin again and decant the supernatant. If the precipitate contains the wanted protein, solve it in pure water and dialyze against an appropriate buffer. 

D 0.5 M EDTA, disodium salt, pH 7.5 E saturated ammonium sulfate solution (see Protocol 4.3) solid ammonium sulfate... 

For description of the amount of ammonium sulfate used for precipitation mostly the term % saturation is used, because at a given temperature the concentration of a saturated ammonium sulfate solution is constant. But because the concentration of saturated solution is temperature dependent, the description should also contain data for temperature of saturated ammonium sulfate solution used for precipitation as well as for sample solution. 

Comparison ofTitanous Chloride and Ferric Ammonium Sulfate Solutions (Determination ofR). This value is necessary in the determination of the normality of the Ti(III) and the normality of the Fe(III). R equals the ml of Ti(lII) reacting with 1.00ml of Fe(III) soln. Sweep the... 

Determination of the Normality of the Ferric Ammonium Sulfate Solution. Using the value of R and the value of the normality of titanous chloride detd in 4.4.3.5.11 and 4.4.3.5.12, calculate the normality of the ferric ammonium sulfate soln... 

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