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Sodium carbonate conversions

The more water molecules there are, the greater the weight of chemical necessary to provide the same activity in solution. For example, the equivalent of 35.0 grams anhydrous would be 41.0 grams of monohydrate (Conversion Tables Sodium Carbonate Conversion Table). [Pg.24]

The water bonded to the chemical makes the molecule weigh more. The extra weight is only water. In practice, this means that if a formula calls for an anhydrous chemical you will need more monohydrate or crystalline chemical to make the same working concentration. You can use the Sodium Carbonate Conversion Table at the end of the book if you have a different hydrate form than called for in the formula. [Pg.164]

Lime Soda. Process. Lime (CaO) reacts with a dilute (10—14%), hot (100°C) soda ash solution in a series of agitated tanks producing caustic and calcium carbonate. Although dilute alkaH solutions increase the conversion, the reaction does not go to completion and, in practice, only about 90% of the stoichiometric amount of lime is added. In this manner the lime is all converted to calcium carbonate and about 10% of the feed alkaH remains. The resulting slurry is sent to a clarifier where the calcium carbonate is removed, then washed to recover the residual alkaH. The clean calcium carbonate is then calcined to lime and recycled while the dilute caustic—soda ash solution is sent to evaporators and concentrated. The concentration process forces precipitation of the residual sodium carbonate from the caustic solution the ash is then removed by centrifugation and recycled. Caustic soda made by this process is comparable to the current electrolytic diaphragm ceU product. [Pg.527]

The oxidant preheater, positioned in the convective section and designed to preheat the oxygen-enriched air for the MHD combustor to 922 K, is located after the finishing superheat and reheat sections. Seed is removed from the stack gas by electrostatic precipitation before the gas is emitted to the atmosphere. The recovered seed is recycled by use of the formate process. Alkali carbonates ate separated from potassium sulfate before conversion of potassium sulfate to potassium formate. Sodium carbonate and potassium carbonate are further separated to avoid buildup of sodium in the system by recycling of seed. The slag and fly-ash removed from the HRSR system is assumed to contain 15—17% of potassium as K2O, dissolved in ash and not recoverable. [Pg.425]

Naphthalenesulfonic Acid. The sulfonation of naphthalene with excess 96 wt % sulfuric acid at < 80°C gives > 85 wt % 1-naphthalenesulfonic acid (a-acid) the balance is mainly the 2-isomer (P-acid). An older German commercial process is based on the reaction of naphthalene with 96 wt % sulfuric acid at 20—50°C (13). The product can be used unpurifted to make dyestuff intermediates by nitration or can be sulfonated further. The sodium salt of 1-naphthalenesulfonic acid is required, for example, for the conversion of 1-naphthalenol (1-naphthol) by caustic fusion. In this case, the excess sulfuric acid first is separated by the addition of lime and is filtered to remove the insoluble calcium sulfate the filtrate is treated with sodium carbonate to precipitate calcium carbonate and leave the sodium l-naphthalenesulfonate/7J(9-/4-J7 in solution. The dry salt then is recovered, typically, by spray-drying the solution. [Pg.489]

Treatment of quinoline with cyanogen bromide, the von Braun reaction (17), in methanol with sodium bicarbonate produces a high yield of l-cyano-2-methoxy-l,2-dihydroquinoline [880-95-5] (5) (18). Compound (5) is quantitatively converted to 3-bromoquinoline [5332-24-1], through the intermediate (6) [66438-70-8]. These conversions are accompHshed by sequential treatment with bromine in methanol, sodium carbonate, or concentrated hydrochloric acid in methanol. Similar conditions provide high yields of 3-bromomethylquinoHnes. [Pg.389]

Mackenzie and Wood obtained low yields by this method, which is the basis of both the Muller and Wislicenus processes, and recommended instead the hydrolysis of acetophenonecyanohydrin (X) into atrolaetie acid (XI), conversion of the latter by distillation under reduced pressure into atropic acid (XII), which was then treated in ethereal solution with hydrochloric acid and the halogen in the resulting, 8-chlorohydratropie acid replaced by hydroxyl, by boiling the acid with aqueous sodium carbonate solution, giving tropic acid (XIII), thus ... [Pg.73]

The conversion of a-methyltropidine into tropidine methiodide was subsequently achieved in another way. By saturating a solution of the base in hydrochloric acid with hydrogen chloride, the elements of the latter were added on in the J -position and the product on treatment with sodium carbonate solution yielded methyl- -tropine. The latter was next brominated in positions 4 and 5, The dibromide, thus formed,... [Pg.78]

One molecular equivalent of 4-methylhexanone-2 is reacted with slightly more than one molecular equivalent of hydroxylamine. Desirably, the hydroxylamine is prepared in the presence of the 4-methylhexanone-2 by reacting the hydrochloride or sulfate or other salt of the hydroxylamine with a suitable base, such as sodium carbonate or sodium hydroxide. Desirably, the reaction mixture is agitated for a few hours to insure the conversion of the 4-methYlhexanone-2 to 4-methylhexanone-2 oxime. [Pg.995]

Ueno and coworkers49 have developed a procedure for the synthesis of chiral sulfinic acids. Treatment of (R)-( + )-23 with disulfide 24 and tributylphosphine in THF gave (S)-( — )-25. Compound 25 was oxidized with potassium permanganate to the sulfone, which was then reduced to the sulfinic acid, (S)-( — )-26, by treatment with sodium borohydride. Conversion of 26 or an analog to an ester would lead to diastereomers. If these epimers could be separated, then they would offer a path to homochiral sulfoxides with stereogenic carbon and sulfur atoms. [Pg.62]

OS 44] ]R 4a] ]P 33] At room temperature, no reaction is observed in the presence or absence of a base using a batch synthesis [7]. Using a base, sodium carbonate (aqueous, 0.2 M, 20 ml water), at 75-80 °C results in 10% conversion after 8 h. The best micro reactor conversion was 68%, using no base and operating at room temperature. [Pg.482]

When scouring synthetic fibres that are to be dyed with disperse dyes, nonionic scouring agents are best avoided unless they are formulated to have a high cloud point and are known not to adversely affect the dispersion properties of the dyes. Conversely, when scouring acrylic fibres, anionic surfactants should be avoided [156] because they are liable to interfere with the subsequent application of basic dyes. These fibres are usually scoured with an ethoxylated alcohol, either alone or with a mild alkali such as sodium carbonate or a phosphate. [Pg.94]

Lowig Also called Ferrite. A causticization process—the conversion of sodium carbonate to sodium hydroxide. The sodium carbonate is mixed with iron oxide and heated for several hours in a rotating kiln. Carbon dioxide is evolved and sodium ferrite remains ... [Pg.167]

Alkylation or acylation takes place at the nitrogen in position 1 when l/7-[l,2,4]triazolo[4,3-A][l,2,4]triazole 9 is treated with methyl iodide or acetyl chloride, furnishing compound 10 or 11, respectively <1983S415>. The 7-methyl isomers 13 are obtained after conversion of compounds 9 into the 1-acetyl derivatives 11 followed by methylation with methyl trifluoromethanesulfonate to give the l-acetyl-6-aryl-7-methyl-3-methylthio-17/-[l,2,4]triazolo[4,3-A]-[l,2,4]triazol-7-ium-trifluoromethanesulfonates 12, which upon treatment with aqueous sodium carbonate afford the 7-methyl derivatives 13 <1985BCJ735>. [Pg.330]

A. Salbutamol Sulphate Boron shows its presence in the above compound as a result of the use of sodium borohydride (NaBH4) in the manufacturing process. The estimation depends upon the conversion of boron to borate and the organic matter is subsequently destroyed by ignition with anhydrous sodium carbonate. The quantity of boron is finally determined by colorimetric assay. [Pg.37]

An intriguing use of a quaternary ammonium salt in a two-phase reaction is to be found with the regeneration of 1 -benzyl-1,4-dihydronicotinamide by sodium dithionite in a biomimetic reduction of thiones to thiols [12], The use of sodium dithionite in the presence of sodium carbonate for the 1,4-reduction of the pyri-dinium salts to 1,4-dihydropyridines is well established but, as both the dithionite and the pyridinium salts are soluble in water and the dihydropyridine and the thione are insoluble in the aqueous phase and totally soluble in the organic phase, it is difficult to identify the role of the quaternary ammonium salt in the reduction cycle. It is clear, however, that in the presence of benzyltriethylammonium chloride, the pyridine system is involved in as many as ten reduction cycles during the complete conversion of the thione into the thiol. In the absence of the catalyst, the thione is recovered quantitatively from the reaction mixture. As yet, the procedure does not appear to have any synthetic utility. [Pg.497]

The oxidation of sulfides to sulfoxides (1 eq. of oxidant) and sulfones (2 eq. of oxidant) is possible in the absence of a catalyst by employing the perhydrate prepared from hexafluoroacetone or 2-hydroperoxy-l,l,l-trifluoropropan-2-ol as reported by Ganeshpure and Adam (Scheme 99 f°. The reaction is highly chemoselective and sulfoxidation occurs in the presence of double bonds and amine functions, which were not oxidized. With one equivalent of the a-hydroxyhydroperoxide, diphenyl sulfide was selectively transformed to the sulfoxide in quantitative yield and with two equivalents of oxidant the corresponding sulfone was quantitatively obtained. 2-Hydroperoxy-l,l,l-fluoropropan-2-ol as an electrophilic oxidant oxidizes thianthrene-5-oxide almost exclusively to the corresponding cw-disulfoxide, although low conversions were observed (15%) (Scheme 99). Deprotonation of this oxidant with sodium carbonate in methanol leads to a peroxo anion, which is a nucleophilic oxidant and oxidizes thianthrene-5-oxide preferentially to the sulfone. [Pg.472]


See other pages where Sodium carbonate conversions is mentioned: [Pg.117]    [Pg.330]    [Pg.331]    [Pg.214]    [Pg.117]    [Pg.330]    [Pg.331]    [Pg.214]    [Pg.85]    [Pg.348]    [Pg.446]    [Pg.145]    [Pg.214]    [Pg.39]    [Pg.1365]    [Pg.426]    [Pg.458]    [Pg.66]    [Pg.140]    [Pg.348]    [Pg.446]    [Pg.20]    [Pg.770]    [Pg.261]    [Pg.107]    [Pg.1821]    [Pg.116]    [Pg.124]    [Pg.50]    [Pg.89]    [Pg.34]    [Pg.448]    [Pg.208]    [Pg.225]   
See also in sourсe #XX -- [ Pg.330 , Pg.331 ]




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