Byproducts sodium sulfate

Mannheim (1) A process for making hydrochloric acid by roasting sulfuric acid and sodium chloride together in a closed cast iron furnace equipped with a plough. The byproduct sodium sulfate, known as salt cake, may be reciystallized after neutralization and filtration, and used as a detergent ingredient. A potassium variant is used in those locations where native potassium chloride can be found. 

Recovery of Caustic Value. Byproduct sodium sulfate is not a readily marketable commodity. The United States alone generates more than 1.5 million tons per year, and those chlor-alkali plants which sell the material may not recover even the cost of crystallization [166]. Modified membrane cells that regenerate caustic soda and sulfuric acid by electrolysis of Na2S04 solution therefore have been studied. These reverse the neutralization reaction and regenerate the acid and base ... 

TTius, the development of dmable anodes and versatile ion-exchange membranes has opened an opportunity for commercialization of sodium sulfate and electrodialysis. Various electrolyzers, processes, and applications have been proposed to handle byproduct sodium sulfate from various industries. Developers include ELTECH Systems Corporation [96] and Aquatech Systems [108]. An estimated capital cost for treating 100,000 tpy of Na2S04 is 200-250 MM [109]. 

In the first case (22), almost stoichiometric amounts of sulfuric acid or chlorosulfonic acid are used. The amine sulfate or the amine chlorosulfate is, first, formed and heated to about 180 or 130°C, respectively, to rearrange the salt. The introduction of the sulfonic acid group occurs only in the ortho position, and an almost quantitative amount of l-aminoanthraquinone-2-sulfonic acid is obtained. On the other hand, the use of oleum (23) requires a large excess of SO to complete the reaction, and inevitably produces over-sulfonated compound such as l-amino-anthraquinone-2,4-disulfonic acid. Addition of sodium sulfate reduces the byproduct to a certain extent. Improved processes have been proposed to make the isolation of the intermediate (19) uimecessary (24,25). 

The aqueous fraction was acidified to pH 1 with 6N HC1, and the small amount of humic acids which precipitated was removed by filtration. The filtrate was extracted three times with 100-ml portions of ethyl acetate. The organic extracts were combined, dried over anhydrous sodium sulfate, and filtered. The solvent was removed by rotary evaporation and the residue contained the freed byproducts from the hydrolyzed esterified and insoluble-bound compounds. 

Pretreatment and recovery of various useful byproducts such as solvents, acids, sodium sulfate, fermentation solids, and fermentation beers comprise a very important waste control strategy for pharmaceutical plants. Such an approach not only makes expensive biological treatment unnecessary, but also gives economic returns in recovery of valuable byproducts [19,21,28-33]. 

Sodium sulfate also is obtained as a byproduct of manufacturing phenol by caustic fusion. 

Sodium sulfate can then easily be separated by washing, because it is water soluble. The use of sulfur was first described in 1820 [3.45]. Roth described the use of K2Cr207 in 1927 [3.46]. If charcoal is used in place of sulfur, Na2C03 is formed as byproduct [3.47],... 

Ammonia-based chemicals appear to have some advantages over sodium systems. They are less costly, and regeneration by conventional means is possible, with the byproduct, ammonium sulfate, a marketable commodity for fertilizer. 

Sodium dichromate manufacture also produces sodium sulfate as a byproduct. 

Sodium sulfate is produced from natural sources and as byproduct in a variety of processes including ascorbic acid, battery recycling, resorcinol, silica pigment, viscose rayon, and sodium bichromate. Other salt cake production processes are based on the reaction of sulfuric acid (Mannheim process) or S02 and air (Hargreaves process) with sodium chloride. The Mannheim process is no longer in use in the United States. U.S. Hargreaves capacity is very limited. However, both processes are used widely in the rest of the world. 

The natural sodium sulfate industry in the United States in 2003 involved two producers, one in California and the other in Texas. On the byproduct manufacturing side, sodium sulfate was recovered in 17 plants across the United States these included ascorbic acid manufacture, battery reclamation, cellulose, rayon, and silica pigments. Approximate consumption of sodium sulfate by end use was soap and detergents, 46 percent pulp and paper, 13 percent textiles, 12 percent glass, 11 percent and others, 23 percent. See Table 26.6 for statistics on sodium sulfate production and consumption. 

Sodium Sulfate. Although considered a weak builder by some manufacturers, sodium sulfate (Na2S04) contributes little to detergent performance. It is commercially available from natural sources and as a byproduct from rayon processing. In dry mix and agglomerated type products, sodium sulfate is used to improve finished product flow characteristics. In spray-dried products, sodium sulfate acts as an inert filler and aids in density control. 

Sodium sulfate is an important heavy chemical in the chemical industry and is found in many mineral deposits. The world reserves are so large that with the present rate of consumption they are sufficient for several hundred years. In addition to extraction from natural sources, it is also produced in large quantities as a byproduct e.g. in the production of potassium salts, sodium chloride and borax and in chemical and metal producing processes. Dedicated manufacture e.g. from sodium chloride and sulfuric acid has become less important. 

Sodium sulfate is produced in large quantities as a byproduct in various chemical and metallurgical processes e.g. in the production of sodium dichromate, vitamin C, formic acid, resorcinol and viscose fibers. 

Sodium sulfate is also formed as a byproduct in the manufacture of hydrogen chloride by the reaction of sodium chloride with sulfuric acid at high temperatures (Mannheim process, Hargreaves process and the fluidized bed process). At the end of the I970 s the Mannheim process was used to produce about half of the sodium sulfate produced in Europe. However, these processes are hardly operated any more. 

Sodium hydrogen sulfate is manufactured by reacting sodium chloride with sulfuric acid in heated cast iron retorts. The liquid product is solidified in refrigeration units. It can also be manufactured in liquid form directly from sodium sulfate and sulfuric acid and is produced as a byproduct in the manufacture of chromic acid, but this is contaminated with Cr(III)- and Cr(VI)-compounds. 

The yellow , i.e. dichromate-colored sodium sulfate byproduct is problematical in that it can not be readily used and the chromium has to be removed in a further process step. 

Derivation (1) Purification of natural sodium sulfate from deposits or brines (2) by-product of hydrochloric acid manufacture from salt and sulfuric acid, 2NaCl + H,S04 2HC1 + Na,S04 (3) byproduct of phenol manufacture (caustic fusion process) (4) Hargreaves process. 

As in the case of many fine chemicals, waste minimization in the liquid streams is a must in the field of cresols and allied products. Many plants producing cresols from coal carhonization process have been closed down because of inherent problems of production of waste materials and byproducts. Same is the story with producers of p-anisic aldehyde using Mn02 as the catalyst. Some manufacturers found it economically not viable to recover both sodium sulfate and manganese sulfate from the waste streams involving etherification of para-cresol and oxidation of p-cresyl methyl ether. These plants were eventually closed down which has been discussed adequately in earlier chapters. 

To get the product, the acetonitrile is evaporated off under a vacuum. The residue is then dissolved in a mixture of 450 ml of chloroform and 60 ml ice water. The chloroform layer is then separated, and the water layer is then extracted four times with 150 ml portions of chloroform. The chloroform extracts are next combined with the original chloroform layer. This combined chloroform solution is next washed a couple of times with 100 ml portions of cold water to remove amine salts. The combined chloroform layers are then dried with a little sodium sulfate, and the chloroform evaporated away under a vacuum to give a solid residue weighing about 10 grams which is a mixture of LSD and iso-LSD and other by products. The other byproducts are the result of non-specific acylation as reported by Garbrecht in the Journal of Organic Chemistry Volume 24, pages 368-... 

These anodes are used extensively in electrogalvanizing, tin electroplating, electrochemical production of copper foil for printed circuit boards, and electrowinning of copper and zinc [91-95]. The application of oxide-coated anodes to sodium sulfate electrolysis so far is small and is not a major driver of electrode development programs. However, environmental concerns associated with byproduct or waste sodium sulfate, along with possible imbalances in the demand for chlorine and caustic soda are enough to maintain interest in the technique. 

Polymixin B sulfate is a cyclic heptapeptide having a linear tripeptide side chain [1368]. This side chain N-terminal is aceylated and the major by-product components are 6-methyloctanoic acid, isooctanoic acid, and heptanoic acid. These byproducts are separated from the parent using a 30 C C,g column (A = 215nm) and a 22.25/50/5/22.75 acetonitrile/water (0.7m/v sodium sulfate)/water (6.8% f 3P04)/water mobile phase. Samples were 0.5mg/mL. Elution was complete in 45 min. The explanation for the long analysis time is that there are another ten unidentified by-products that are resolved from the peaks of interest. Plots of the effects of percent acetonitrile and concentrations of sodium sulfate and H3PO4 are presented. 

Of the various byproduct utilization options, the most attractive is the separation and recovery of sodium sulfate for sale or reuse (Bennett and Nastri, 1990). Reuse options include recovery and use of sodium compounds in mineral filler, grout, and bricks (Eklund and Golden, 1990). Producing high purity Na2S04 for sale by dissolving the byproduct and... 

A mechanism is shown below. First, an acetylide ion functions as a nucleophile and attacks one of the methyl groups of dimethyl sulfate, thereby methylating the acetylide ion, giving propyne. Then, another acetylide ion attacks the remaining methyl group, to give a second equivalent of propyne. The ionic byproduct is Na2S04 (sodium sulfate), as shown. 

The viscosity of alcohol sulfate and alcohol ether sulfate solutions is sensitive to the amount of byproducts contained in the solution. Putnik and McGuire [76] developed an empirical equation [Eq. (10)] relating the kinematic viscosity of a sodium C12-C16 alcohol sulfate to the weight percentages of free oil (FO), sulfate ion (S04), and chloride ion (Cl) ... 

Impurities consist of unreacted material, including alkanes and internal or branched alkenes, and other material which can be detected in the neutral oil fraction of AOS. Examination of this fraction also indicates the amount of unhydrolyzed material (sulfonate esters and sultones) and byproducts (secondary alcohols, unsaturated and 2-chloro-y-sultones) in the sample. Salt calculations are made to determine inorganic sulfates and sodium chloride. Determinations for alkalinity, color, and water are required to meet product... 

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