Sodium carbonate production

To 25.5 g of NaCN at 10-20°C ware added dropwise under stirring 64 ml of glacial acetic acid and ten at 20°C a mixture of 70 ml concentrated sulfuric acid and 64 ml of glacial acetic acid. To the prepared mixture at 20-25°C was added dropwise 82 g of 2-phenyl-3-methylbutanol. The mixture was stirred at 45-50°C for 10-20 min and then at 75°C for 30 min. To the reaction mixture was added 750 ml of water. The acids was neutralized with sodium carbonate. Product was extracted with ether and distilled. Boiling point of (dimethylbenzylcarbinyl)formamide 173-176°C/0 mm, yield 63 g. 

The world production of sodium carbonate has increased considerably from 12.7 10 t in 1960 to 20.6 10 t in 1970 to 31.5 10 t in 1993, which, except for production in the USA, was almost exclusively synthetic. The capacity in the Federal Republic of Germany is currently 1.9 10 t/a. USA production increased from ca. 7.7 10 t in 1981, of which 90% was from natural deposits, to 11 10 t/a in 1994, which was exclusively from natural deposits. In 1970, sodium carbonate from natural deposits accounted for 15% of the worldwide production. This proportion had increased to 35% by 1994. Further advances in the economics of sodium carbonate production from natural deposits are to be expected upon changing from mining to extraction as an aqueous solution, so-called solution mining . The high energy costs of sodium carbonate manufacture and stricter environment protection... 

Sodium Carbonate Production from Natural Deposits... 

Economic Importance The production of sodium hydrogen carbonate is much lower than that of sodium carbonate. The production in the USA in 1995 was 0.454 10 t being only ca. 5% of the sodium carbonate production and corresponding to 50% of the world production of 0.895 10 t. The capacity in the USA has expanded considerably in recent years and as a result production should increase by 2% per year in coming years. A plant for producing sodium hydrogen carbonate from natural deposits came on stream in the USA in 1991. 

The molarity of a perchloric acid solution was established by titration against primary-standard sodium carbonate (product CO2) the following data were obtained. I... 

Sodium carbonate production from natural sources of solid beds of trona (Na2C03 2Na2S04), trona and sodium carbonate-rich brines, and nahcolite mineral became important much more recently since the discovery of major deposits of these minerals in the U.S. For those nations with well defined, suitable deposits of these minerals the incentives for sodium carbonate production from these sources are substantial a halving of the capital costs of a similarly sized Solvay plant, and much less potential for environmental problems. For these reasons, the U.S., with proven mineral reserves containing the equivalent of over 23 billion tonnes of sodium carbonate [18], has been the world s largest producer of sodium carbonate in recent years, with 10.5 million tonnes in 2002. 

A shift to the processing of substantial alternate natural mineral sources of sodium carbonate in the U.S. has eliminated the calcium chloride disposal problems of the Solvay process for sodium carbonate production. Coupling this advantage to the much lower capital cost of a natural sodium carbonate plant has contributed to the shift away from synthetic sodium carbonate in the U.S. [13] (Table 7.3). Kenya is the only other country reported to be recovering natural sodium carbonate and was operating at 260,000 metric toimes in 2001 [19]. China, the second largest producer, and all other world producers still rely heavily on the ammonia-soda process [17, 24] (Table 7.4). 

TABLE 7.3 Growth of Natural Sodium Carbonate Production at the Expense of Synthetic Material in the LI.S."... 

SAMSCO has provided with us with a sample of their sodium carbonate product. Please write your report to Jimmy Prophet at SAMSCO. Thank you. 

Scheme 2.1 Leblanc process for sodium carbonate production...

Qualitative examples abound. Perfect crystals of sodium carbonate, sulfate, or phosphate may be kept for years without efflorescing, although if scratched, they begin to do so immediately. Too strongly heated or burned lime or plaster of Paris takes up the first traces of water only with difficulty. Reactions of this type tend to be autocat-alytic. The initial rate is slow, due to the absence of the necessary linear interface, but the rate accelerates as more and more product is formed. See Refs. 147-153 for other examples. Ruckenstein [154] has discussed a kinetic model based on nucleation theory. There is certainly evidence that patches of product may be present, as in the oxidation of Mo(lOO) surfaces [155], and that surface defects are important [156]. There may be catalysis thus reaction VII-27 is catalyzed by water vapor [157]. A topotactic reaction is one where the product or products retain the external crystalline shape of the reactant crystal [158]. More often, however, there is a complicated morphology with pitting, cracking, and pore formation, as with calcium carbonate [159]. 

All the products of Clemmensen reductions contain small amounts of un-saturated hydrocarbons. These can be removed by repeated shaking with 10 per cent, of the volume of concentrated sulphuric acid until the acid is colourless or nearly so each shaking should be of about 5 minutes duration. The hydrocarbon is washed with water, 10 per cent, sodium carbonate solution, water (twice), dried with anhydreus magnesium or calcium sulphate, and finally distilled twice from a Claisen flask with fractionating side arm (or a Widmer flask) over sodium. 

Add 1 ml. of the alcohol-free ether to 0-1-0-15 g. of finely-powdered anhydrous zinc chloride and 0 5 g. of pure 3 5-dinitrobenzoyl chloride (Section 111,27,1) contained in a test-tube attach a small water condenser and reflux gently for 1 hour. Treat the reaction product with 10 ml. of 1-5N sodium carbonate solution, heat and stir the mixture for 1 minute upon a boiling water bath, allow to cool, and filter at the pump. Wash the precipitate with 5 ml. of 1 5N sodium carbonate solution and twice with 6 ml. of ether. Dry on a porous tile or upon a pad of filter paper. Transfer the crude ester to a test-tube and boil it with 10 ml. of chloroform or carbon tetrachloride filter the hot solution, if necessary. If the ester does not separate on cooling, evaporate to dryness on a water bath, and recrystallise the residue from 2-3 ml. of either of the above solvents. Determine the melting point of the resulting 3 5 dinitro benzoate (Section 111,27). 

In a 1 htre round bottomed flask equipped with a reflux condenser place a solution of 62 -5 g. of anhydroas sodium carbonate in 500 ml. of water and add 50 g. of commercial 2 4-dinitro-l-chlorobenzene. Reflux the mixture for 24 hours or until the oil passes into solution. Acidify the yellow solution with hj drochloric acid and, when cold, filter the crystaUine dinitrophenol which has separated. Dry the product upon filter paper in the air. The yield is 46 g. If the m.p, differs appreciably from 114°, recrystallisc from alcohol or from water. 

Equip a I litre three-necked flask with a mechanical stirrer and a thermometer, and immerse the flask in a bath of ice and salt. Place 306 g. (283 ml.) of acetic anhydride, 300 g. (285 ml.) of glacial acetic acid and 25 g. of p-nitrotoluene in the flask, and add slowly, with stirring, 42 5 ml. of concentrated sulphuric acid. When the temperature has fallen to 5°, introduce 50 g. of A.R. chromic anhydride in small portions at such a rate that the temperature does not rise above 10° continue the stirring for 10 minutes after all the chromium trioxide has been added. Pour the contents of the flask into a 3 litre beaker two-thirds filled with crushed ice and almost fill the beaker with cold water. Filter the solid at the pump and wash it with cold water until the washings are colourless. Suspend the product in 250 ml. of cold 2 per cent, sodium carbonate solution and stir mechanically for 10-15 minutes filter (1), wash with cold water, and finally with 10 ml. of alcohol. Dry in a vacuum desiccator the yield of crude p-nitrobenzal diacetate is 26 g. (2),... 

Hydrolysis may be effected with 10-20 per cent, sodium hydroxide solution (see p-Tolunitrile and Benzonitrile in Section IV,66) or with 10 per cent, methyl alcoholic sodium hydroxide. For diflScult cases, e.g., a.-Naphthoniirile (Section IV,163), a mixture of 50 per cent, sulphuric acid and glacial acetic acid may be used. In alkahne hydrolysis the boiling is continued until no more ammonia is evolved. In acid hydro-lysis 2-3 hours boiling is usually sufficient the reaction product is poured into water, and the organic acid is separated from any unchanged nitrile or from amide by means of sodium carbonate solution. The resulting acid is identified as detailed in Section IV,175. 

Propiophenone. Prepare a solution of diphenyl-cadmium in 110 ml. of dry benzene using 4 9 g. of magnesium, 32 4 g. of bromobenzene and 19 5 g. of anhydrous cadmium chloride. Cool the solution to 10°, and add during 3 minutes a solution of 14 -8 g. of propionyl chloride (b.p. 78-79°) in 30 ml. of dry benzene use external coohng with an ice bath to prevent the temperature from rising above 40°. Stir the mixture for 2 hours at 25-35°. Work up the product as detailed above except that 6 per cent, sodium carbonate solution should replace the saturated sodium bicarbonate solution. The yield of propiophenone, b.p. 100-102°/16 mm., is 17 6 g. 

The mother liquors from the washings and recrystallisations are saved for the recovery of the 4-nitrophthalic acid. The combined mother liquors ore concentrated to a small bulk and the acid is extracted with ether. Upon esterification by the Fischer - Speier method, the 3-nitro acid forms only the acid ester and may be removed by shaking the product with sodium carbonate solution, whilst the neutral ester of 4-iiitrophthalic acid remains unaffected. Hydrolysis of the neutral ester gives the pure 4-nltrophthalio acid, m.p. 165°. 

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