Ammonium bisulfite solutions

Ammonia Solutions. It has long been suggested that ammonia solutions age quicker than sodium or potassium solutions of sulfite. We have recorded Raman spectra of three year old 1 M ammonium bisulfite solutions in sealed ampules. These contain not only a solid elemental sulfur phase and solid ammonium sulfate phase, but the liquid phase contains also several percent of dithionate, recognizable by the vibration frequencies of 710 cm- and 1206 cm-, with an intensity ratio of l7io/ -l2Q6 = 3.2. A search for other oxyacids yielded traces of thiosulfate... 

Figure 1. Raman spectra of ammonium bisulfite solution.

AMMONIUM BISULFITE SOLUTION 2733 29 POI.YALKYI MINES. flammable, corrosive, n.o.s. 

Ammonium bisulfite can be used in place of the sulfur dioxide. The solution is treated with activated carbon and filtered to remove traces of sulfur. Excess ammonia is added and the solution evaporated if the anhydrous crystalline form is desired. The crystals ate dried at low temperature in the presence of ammonia to prevent decomposition (61—63). 

Both batch and continuous processes employ excess sulfur and operate at 85—110°C. Trace amounts of polysulftdes produce a yellow color which iadicates that all the ammonium sulfite has been consumed. Ammonium bisulfite is added to convert the last polysulfide to thiosulfate and the excess ammonia to ammonium sulfite. Concentrations of at least 70% (NH 2S2 3 obtained without evaporation. Excess sulfur is removed by filtration and color is improved with activated carbon treatment or sodium siUcate (66). Upon cooling the aqueous concentrated solution, ammonium thiosulfate crystallines. 

The catalyst was removed by filtration. The filtrate was diluted to about 18 liters, and was acidified with 15 ml concentrated hydrochloric acid. With vigorous stirring, 1,152 ml N KICI2 solution were run into the diluted filtrate over a period of about 20 to 30 minutes. A solid precipitate was formed, and was filtered off after about six hours. The sol id material was washed with water, with sodium bisulfite solution, and again with water. It was dissolved in aqueous ammonium hydroxide solution, the solution was filtered, and the filtrate was acidified with concentrated hydrochloric acid containing a small amount of sodium bisulfite. After a short time, the precipitate formed was filtered with suction, washed with water, and dried. 

To a large bottle are added 470.0 gm (5.6 moles) of 2-methyl-3-butyne-2-ol, 1000 ml of 48 % technical grade hydrobromic acid, 200.0 gm (2.04 moles) of ammonium bromide, and 70.0 gm (0.71 mole) of cuprous chloride. The bottle is sealed, shaken at room temperature for 4J hr, opened, and the organic layer is separated. The organic layer is washed twice with sodium bicarbonate solution, once with a saturated sodium bisulfite solution, dried over calcium chloride, and fractionally distilled through a glass-helix-packed column to afford 500 gm (61 %) of almost pure product (ir 1956 cm-1 allene), b.p. 34°C (18 mm), d5 1.5163. The ir showed that the product contained a trace of l-bromo-3-methyl-1,3-butadiene (1580 and 1620 cm-1). 

Tail gas scmbbers are sometimes used on single absorption plants to meet S02 emission requirements, most frequently as an add-on to an existing plant, rather than on a new plant. Ammonia (qv) scrubbing is most popular, but to achieve good economics the ammonia value must be recovered as a usable product, typically ammonium sulfate for fertilizer use. A number of other tail gas scrubbing processes are available, including use of hydrogen peroxide, sodium hydroxide, lime and soda ash. Other tail gas processes include active carbon for wet oxidation of S02, molecular sieve adsorbents (see MoLECULARSIEVEs), and the absorption and subsequent release of S02 from a sodium bisulfite solution. 

Solutions containing ammonium sulfate, with or without the addition of ammonium hydroxide, have been widely used. The ammonium system can operate effectively only within a pH range of 4.0 to 7.0. As the pH value increases above 7.0, progressively more gaseous ammonia is liberated and this reacts in the gaseous phase with water vapor and SO2 to produce a dense aerosol (white plume) which is difficult for scrubbers to remove. In an ammonia system, in order to regenerate the scrubbing solution, the ammonium bisulfite and sulfite mixture is heated... 

The so-called soluble bases now are used, with each having certain advantages. Because solutions of sodium, magnesium, and ammonium bisulfite are all soluble at pH 4.5, the current practice is to pulp at the higher pH, which is usually called bisulfite pulping. Extremely long cooking times (7-10 hr) are necessary with acid sulfite, whereas 4-5 hr is sufficient with bisulfite. 

Ammonia scrubbing is one of many processes for removing sulfur dioxide from flue gases. The gases are bubbled through an aqueous solution of ammonium sulfite, and the SO2 reacts to form ammonium bisulfite ... 

Preparation of Fremy s salt a freshly prepared sodium bisulfite solution (100 ml) is added to a mixture of sodium nitrite (345 g) and ice (200 g) in a 1-1 beaker. On addition of 20 ml of glacial acetic acid, the reaction mixture turns black. Concentrated ammonium hydroxide (25 ml) is added and the mixture is cooled in an ice bath. A 0.2 M solution (400ml) of potassium permanganate is added dropwise over 1 h and the black precipitate which forms is immediately removed by filtration. A saturated solution of potassium chloride (250 ml) is added slowly over a 45-min period while the filtrate is gently stirred in an ice water bath. The precipitate that forms is collected by filtration and washed successively with a saturated solution of potassium chloride and methanol, each containing 5% of concentrated ammonium hydroxide and, finally, with acetone. Fremy s salt should be stored in a desiccator over calcium oxide. A small amount of ammonium carbonate in a desiccator is also very effective in protecting Fremy s salt against deeomposition. 

AMMONIUM BISULFITE or AMMONIUM BISULPHITE (10192-30-0) Reacts with water, steam, or acids, forming corrosive acid solution and sulfur oxide fumes. Incompatible with lead diacetate, mercury(I) chloride. 

Volgin,B.P., Efimova,T.F. and Gofman.M.S. "Absorption of sulfur dioxide by ammonium sulfite-bisulfite solution in a venturi scrubber". Int.Chem.Engng.8 (1968) 113. 

The use of the DC/DA system adds 10%-15% to the cost of the plant in comparison with the older singleabsorption process. It also uses more energy and produces less steam or other recoverable energy. The residual quantities of SO2 can also be removed by scrubbing the stack gases with an ammonia solution. The resultant ammonium sulfite/bisulfite solution is then acidulated with sulfuric acid to produce ammonium sulfate and SO2. 

Alternatively, the ammonium sulfite-bisulfite solution may be acidulated with phosphoric acid, producing an ammonium phosphate solution. There are nurnerous other tail-gas scrubbing processes that produce various byproducts or waste products [5]. 

Aluminum Chloride, 200 F Ammonium Bisulfite, 150 F Ammonium Chloride, 200 F Ammonium Sulfate, 200 F Amyl Acetate, 200° F Amyl Alcohol, 175 F Amyl Chloride, 200 F Aniline, 150 F Anod zing Solutions, 200 F Antimony Trichloride, 150 F Benzaldehyde, 200 F Benzene, toiling Benzene Hexachloride, 175 F Black Liquor, 200 F Brine, 200 F... 

Spent solution from the SOj absorber, containing ammonium bisulfite and ammonium sulfite, is reacted with ammonium bisulfate according to the following equations ... 

The hot gas fiom the incinerator is partially cooled to about 500°F by a heat recovery steam generator. The gas then flows through a de-superheater and a quench vessel. The quench vessel temperature is monitored to ensure that the gas entering the first absorber stage is cool enough to avoid damage to the fiber reinforced plastic absorption vessels. The gas then flows countercurrently through three absorbers where the SO2 is reacted with aqueous ammonia and converted to an aqueous solution of ammonium bisulfite and ammonium sulfite ... 

In the basic form of the Katasulf process, the gas was first passed through an electrostatic filter for tar removal and then preheated to 750°F by heat exchange with the gas leaving the catalytic converter. After addition of air, the gas was admitted to the catalyst chamber where the H2S was converted to SO2. Because of the exothermic nature of the reaction, the gas temperature increased considerably in the converter. The exit gas was partially cooled by heat exchange with the incoming gets. It was then passed through an absorption lower where ii was washed countercurrently with a concentrated aqueous ammonium sulfite-bisulfite solution, which absorbed both the SO2 and NH3. 

The circulating ammonium sulfite-bisulfite solution was maintained at a salt concentration of 50 to 60% by continuous withdrawal of a side stream. This stream was acidified with sulfuric acid, and the resulting salts converted to ammonium sulfate in solution and liquid elemental sulfur by heating under pressure at 290°F. 

Figures 5.2 and 5.3 show the effect of hydrogen sulfide on ammonium bisulfite when used as an oxygen scavenger in aqueous solutions.

In a typical adiabatic polymerization, approximately 20 wt % aqueous acrylamide is charged into a stainless steel reactor equipped with agitation, condenser, and cooling jacket or coils. To initiate the polymerization, an aqueous solution of sodium bisulfite [7631-90-5] is added, followed by the addition of a solution of ammonium persulfate [7727-54-0] N2HgS20g. As the polymerization proceeds, the temperature rises to about 90°C, and then begins to fall at the end of the polymerization. The molecular weight obtained depends primarily on the initiator concentration employed. 

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