Compounds solubility

Girard s reagents Quaternary ammonium salts of the type Me3NCH2CONHNH2 X which form water-soluble compounds with aldehydes and ketones, and are therefore separable from other neutral compounds the aldehyde or ketone may be subsequently regenerated after separation. 

C7HgN402. Occurs to a small extent in tea, but is chiefly prepared synthetically. Like caffeine, it is a very weak base which forms water-soluble compounds with alkalis. It has a similar pharmacological mechanism to that of caffeine and is used, in combination with ethy-lenediamine. as a diuretic and a bron-chodilator. 

The essential basis of the scheme for the separation of water-soluble compounds is, therefore, distillation of (a) an aqueous solution of the mixture, (b) an alkaline (with sodium hydroxide) solution of the mixture, and (c) an acidic (with sulphuric oj phosphoric acid) solution of the mixture. The residue will contain the non-volatile components, which must be separated from inorganic salts and from each other by any suitable process. 

Exposure to nickel metal and soluble compounds (as Ni) should not exceed 0.05 mg/cms (8-hour time-weighted average - 40-hour work week). Nickel sulfide fume and dust is recognized as being potentially carcinogenic. 

The 0X0 and aldol reactions may be combined if the cobalt catalyst is modified by the addition of organic—soluble compounds of 2inc or other metals. Thus, propylene, hydrogen, and carbon monoxide give a mixture of aldehydes and 2-ethylhexenaldehyde [123-05-7] which, on hydrogenation, yield the corresponding alcohols. 

On archaeological glass objects, layers of reaction products are formed and the main constituents of these cmsts are the less-soluble compounds such as siHca and calcium carbonate, which becomes calcium sulfate. 

Dibarium hexakiscyanoferrate [13821 -06-2], Ba2[Fe(CN)g], is a sparingly water-soluble compound prepared by addition of a solution of... 

The lanthanides form many compounds with organic ligands. Some of these compounds ate water-soluble, others oil-soluble. Water-soluble compounds have been used extensively for rare-earth separation by ion exchange (qv), for example, complexes form with citric acid, ethylenediaminetetraacetic acid (EDTA), and hydroxyethylethylenediaminetriacetic acid (HEEDTA) (see Chelating agents). The complex formation is pH-dependent. Oil-soluble compounds ate used extensively in the industrial separation of rate earths by tiquid—tiquid extraction. The preferred extractants ate catboxyhc acids, otganophosphoms acids and esters, and tetraaLkylammonium salts. 

Some nonmalignant respiratory effects have been observed in experimental animals during acute or subchronic exposures. Soluble and moderately soluble compounds were more toxic than were insoluble compounds and produced different effects. Sulfate and subsulftde produced fibrosis whereas nickel oxide did not. 

Uranium Purification. Subsequent uranium cycles provide additional separation from residual plutonium and fission products, particularly zirconium— niobium and mthenium (30). This is accompHshed by repeating the extraction/stripping cycle. Decontamination factors greater than 10 at losses of less than 0.1 wt % are routinely attainable. However, mthenium can exist in several valence states simultaneously and can form several nitrosyl—nitrate complexes, some for which are extracted readily by TBP. Under certain conditions, the nitrates of zirconium and niobium form soluble compounds or hydrous coUoids that compHcate the Hquid—Hquid extraction. SiUca-gel adsorption or one of the similar Hquid—soHd techniques may also be used to further purify the product streams. 

The batch and fed-batch procedures are used for most commercial antibiotic fermentations. A typical batch fermentor may hold over 150,000 Hters. When a maximum yield of antibiotic is obtained, the fermentation broth is processed by purification procedures tailored for the specific antibiotic being produced. Nonpolar antibiotics are usually purified by solvent extraction procedures water-soluble compounds are commonly purified by ion-exchange methods. Chromatography procedures can readily provide high quaHty material, but for economic reasons chromatography steps are avoided if possible. 

Properties. Sulfolane [126-33-0] C4HgS02 (1), also known as tetrahydrothiophene-1,1-dioxide and tetramethylene sulfone, is a colorless, highly polar, water-soluble compound. Physical properties are given ia Table 1 (1). 

Orally in rats, the toxicity of sodium tungstate was highest, tungsten trioxide was intermediate, and ammonium tungstate [15855-70-6] lowest (59,60). In view of the degree of systemic toxicity of soluble compounds of tungsten, a threshold limit of 1 mg of tungsten per m of air is recommended. 

Many of the heavy metal xanthates have been piepaied from aqueous solutions of the alkah metal xanthates and the water-soluble compound of the heavy metal desired. 

The water solubiUty of zinc compounds varies greatly, as shown in Table 1. Water-soluble compounds not Hsted are zinc formate [557-41-5] chlorate [10361-95-2] fluorosihcate [16871 -71 -9] and thiocyanate [557-42-6]. Also, the water-soluble amino and cyanide complexes have many uses. 

The gels precipitated as described above are not useful in ion-exchange systems because their fine size impedes fluid flow and allows particulate entrainment. Controlled larger-sized particles of zirconium phosphate are obtained by first producing the desired particle size zirconium hydrous oxide by sol—gel techniques or by controlled precipitation of zirconium basic sulfate. These active, very slightly soluble compounds are then slurried in phosphoric acid to produce zirconium bis (monohydrogen phosphate) and subsequently sodium zirconium hydrogen phosphate pentahydrate with the desired hydrauhc characteristics (213,214). 

Soluble Compounds. The mechanism of barium toxicity is related to its ability to substitute for calcium in muscle contraction. Toxicity results from stimulation of smooth muscles of the gastrointestinal tract, the cardiac muscle, and the voluntary muscles, resulting in paralysis (47). Skeletal, arterial, intestinal, and bronchial muscle all seem to be affected by barium. 

More recendy, the molten caustic leaching (MCL) process developed by TRW, Inc. has received attention (28,31,32). This process is illustrated in Eigure 6. A coal is fed to a rotary kiln to convert both the mineral matter and the sulfur into water- or acid-soluble compounds. The coal cake discharged from the kiln is washed first with water and then with dilute sulfuric acid solution countercurrendy. The efduent is treated with lime to precipitate out calcium sulfate, iron hydroxide, and sodium—iron hydroxy sulfate. The MCL process can typically produce ultraclean coal having 0.4 to 0.7% sulfur, 0.1 to 0.65% ash, and 25.5 to 14.8 MJ/kg (6100—3500 kcal/kg) from a high sulfur, ie, 4 wt % sulfur and ca 11 wt % ash, coal. The moisture content of the product coal varies from 10 to 50%. 

Dicyandiamide may be treated with formaldehyde (49) to produce resiaous compositions of varyiag properties (see Amino resins and plastics), under either acid or alkaline conditions. The reaction can be controlled to give mainly monomethyloldicyandiamide, a very water-soluble compound ... 

The pH value and thus the OH ion concentration is important in the formation of surface films, since OH" ions generally form difficultly soluble compounds with metal ions (see Section 2.2.3.1). pH is an important parameter of the medium. One... 

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