Sodium industrial production

The viscosity of solutions is quite temperature dependent increasing the temperature leads to a reduction in viscosity, which approaches zero at approximately 60°C (322). The viscosity is relatively stable from pH 3—10 and is compatible with a number of inorganic salts other than sodium. The production of succinoglycan and its potential use in foods and industrial processes as a thickening agent has been described (322). 

The armual world production of sodium nitrate was steady throughout the early 1990s. About 85% is suppHed by the natural product. The maximum world production of sodium nitrate occurred around 1930, at 3,000,000 t/yr, but the highest production levels attained by the Chilean nitrate industry (ca 2,900,000 t/yr) occurred in the late 1920s. Synthetic sodium nitrate production peaked in the mid-1930s at 730,000 t/yr. During that period, the Chilean industry production decreased to 1,360,000 t/yr. 

Industrial production of sodium nitrite is by absorption of nitrogen oxides (NO ) into aqueous sodium carbonate or sodium hydroxide. NO gases originate from catalytic air oxidation of anhydrous ammonia, a practice common to nitric acid plants ... 

In 1980, >1 one million ts of sodium sulfate were consumed in the United States, but this had declined to <600, 000 t by the end of 1994. The decline is partly a result of higher energy prices and more efficient use of Na2S04 by the paper industry. At one time the kraft paper industry consumed two-thirds of sodium sulfate production. Pressures on paper producers to clean effluent streams and reduce energy forced improvements in internal processes and recycling of sodium sulfate (11,12). 

In industrial production of acid-modified starches, a 40% slurry of normal com starch or waxy maize starch is acidified with hydrochloric or sulfuric acid at 25—55°C. Reaction time is controlled by measuring loss of viscosity and may vary from 6 to 24 hs. For product reproducibiUty, it is necessary to strictly control the type of starch, its concentration, the type of acid and its concentration, the temperature, and time of reaction. Viscosity is plotted versus time, and when the desired amount of thinning is attained the mixture is neutralized with soda ash or dilute sodium hydroxide. The acid-modified starch is then filtered and dried. If the starch is washed with a nonaqueous solvent (89), gelling time is reduced, but such drying is seldom used. Acid treatment may be used in conjunction with preparation of starch ethers (90), cationic starches, or cross-linked starches. Acid treatment of 34 different rice starches has been reported (91), as well as acidic hydrolysis of wheat and com starches followed by hydroxypropylation for the purpose of preparing thin-hoiling and nongelling adhesives (92). 

Large-Scale Industrial Production. Large amounts of chlorine dioxide ate used in pulp bleaching and smaller quantities ate used for the manufacture of sodium chlorite. In these appHcations, sodium chlorate is the only commercially available taw material. Chlorine dioxide production from sodium chlorate is achieved by the reduction of the chlorate ion in the presence of strong acid. The reaction consumes acid, so that acid and reducing agents must be constantly added to maintain the reaction. 

Economic Aspects. Sodium chlorate production has grown at about a 5% rate since the early 1970s and is expected to grow at 8—10% through 1995. The projected rapid growth is related to the increased use of chlorine dioxide in the pulp and paper industry. The 1991 production capacities of various North American plants are given in Table 7. The price of sodium chlorate has increased from 165/t in 1970 to about 480/t in 1991 (113,114). 

Industrial Production and Uses of Sodium Carbonate, Hydroxide and Sulfate ... 

In asymmetric Strecker synthesis ( + )-(45,55 )-5-amino-2,2-dimethyl-4-phenyl-l,3-dioxane has been introduced as an alternative chiral auxiliary47. The compound is readily accessible from (lS,25)-2-amino-l-phcnyl-l,3-propancdioI, an intermediate in the industrial production of chloramphenicol, by acctalization with acetone. This chiral amine reacts smoothly with methyl ketones of the arylalkyl47 or alkyl series48 and sodium cyanide, after addition of acetic acid, to afford a-methyl-a-amino nitriles in high yield and in diastereomerically pure form. 

K.18 The industrial production of sodium metal and chlorine gas makes use of the Downs process, in which molten sodium chloride is electrolyzed (Chapter 12). Write a balanced equation for the production of the two elements from molten sodium chloride. Which element is produced by oxidation and which by reduction ... 

The alkyl halide (ethyl bromide in the above equation) can react further with the primary amine produced to give a secondary amine and with that to form a tertiary amine and finally a quaternary ammonium salt. Quaternary ammonium hydroxides are very strong bases like sodium hydroxide. Tetramethylammonium hydroxide is a very important chemical used in the manufacture of semiconductors and other electronic industry products. 

Highly active CuCl catalysts for the direct process of methylchlorosilane synthesis were prepared by reducing Cu with a sodium sulfite solution in the presence of dispersing agents. Several well-known dispersants, e.g. SDBS, were used in this study. When SDBS was used, a catalyst in the form of small flakes was obtained that gave the best performance in reactivity, product selectivity and silicon conversion. This provides a convenient way to prepare the CuCl catalyst for use in industrial production. 

A number of electrolytic processes are used for the industrial production of metals. Some metals such as zinc, copper, manganese, gallium, chromium, etc. are electrowon from aqueous baths. Another common electrolytic process used is molten salt electrolysis. The most important application of molten salt electrolysis till now has been in the electrowinning of metals. Today aluminum, magnesium, lithium, sodium, calcium, boron, cerium, tantalum, and mischmetal are produced in tonnage quantities by molten salt electrolysis. As a representative example, the electrowinning process for aluminum is taken up. 

The industrial production of Prussian blue is based on the reaction in aqueous solution of sodium hexacyanoferrate(n), Na4Fe(CN)6, with iron(n) sulfate, FeS04-7H20 in the presence of an ammonium salt, which results initially in the formation of the colourless insoluble iron(n) hexa-cyanoferrate(n) (Berlin white). Prussian blue is generated by subsequent oxidation with a dichromate or chlorate. 

The industrial production of sodium chlorate is by electrolysis of an aqueous solution of NaCl, which can be shown as... 

The sulfoxidation of aliphatic hydrocarbons is the easiest method for the synthesis of alkylsulfonic acids. Their sodium salts are widely used as surfactive reactants in technology and housekeeping. Platz and Schimmelschmidt [1] were the first to invent this synthetic method. Normal paraffins (Ci4-Cig) are used for the industrial production of alkylsulfonic acids [2-4]. Olefins and alkylaromatic hydrocarbons do not produce sulfonic acids under the action of sulfur dioxide and dioxygen and retard the sulfoxidation of alkanes [5-9],... 

Nuclear and magneto-hydrodynamic electric power generation systems have been produced on a scale which could lead to industrial production, but to-date technical problems, mainly connected with corrosion of the containing materials, has hampered full-scale development. In the case of nuclear power, the proposed fast reactor, which uses fast neutron fission in a small nuclear fuel element, by comparison with fuel rods in thermal neutron reactors, requires a more rapid heat removal than is possible by water cooling, and a liquid sodium-potassium alloy has been used in the development of a near-industrial generator. The fuel container is a vanadium sheath with a niobium outer cladding, since this has a low fast neutron capture cross-section and a low rate of corrosion by the liquid metal coolant. The liquid metal coolant is transported from the fuel to the turbine generating the electric power in stainless steel... 

The electrolysis of molten sodium chloride is an important industrial reaction. Figure 11.15 shows the large electrolytic cell used in the industrial production of sodium and chlorine. You will meet other industrial electrolytic processes later in this chapter. 

Electrolysis ol the fused alkali hydroxide.—At the time of Davy s discovery the dynamo had not been invented, and the electric current derived from batteries was far too costly for the production of sodium on a manufacturing scale. In modern works, where cheap electrical energy is available, modifications of Davy s original process—electrolysis of fused sodium hydroxide—are used for preparing sodium industrially —e.g. H. Y. Castner s electrolytic process (1890).a Potassium can also be made by H. Y. Castner s process. 

On the other hand, application of alkali metal amalgam permits the slowing down of the reaction of metals with alcohols, which is used in the industrial production of alkali metals alkoxides. Production of NaOR by Mathieson Alkali Works is based, for instance, on the reaction of sodium amalgam (formed as a result of the electrolysis of aqueous NaCl solution with the mercury cathode) with alcohol NaOR ROH is isolated from the solutions. Na residue in the amalgam is hydrolyzed, the obtained mixture is returned to the electrolyz-... 

Most industrial production of metallic sodium is accomplished by passing an electric current through molten sodium chloride. Chlorine gas also is produced. 

Another classic resolution process developed by Ethyl Corp. for (S)-ibuprofen production uses (S)-(-)-a-methylbenzylamine (MAB) as the chiral base for diastereomeric salt formation 49 The difference in solubility between (S)- and (ft)-ibuprofen MAB salts is so substantial that only half an equivalent of MAB is used for each mole of racemic ibuprofen, and no seeding is needed. The process can also be performed in a wide range of solvents, and the unwanted (ft)-ibuprofen can be recycled conveniently by heating the mother liquor in sodium hydroxide or hydrochloric acid. Other designer amines have been developed for resolution of ibuprofen with good stereoselectivities,50 but these chiral amines were prepared specifically for ibuprofen resolution and are thus unlikely to be economical for industrial production. 

The industrial production of Crixivan (9 H2S04) took advantage of the chirality of (IS,2R)-aminoindanol to set the two central chiral centers of 9 by an efficient diastereoselective alkylation-epoxidation sequence.17 The lithium enolate of 12 reacted with allyl bromide to give 13 in 94% yield and 96 4 diastereoselective ratio. Treatment of a mixture of olefin 13 and V-chlorosuccinimide in isopropyl acetate-aqueous sodium carbonate with an aqueous solution of sodium iodide led to the desired iodohydrin in 92% yield and 97 3 diastereoselectivity. The resulting compound was converted to the epoxide 14 in quantitative yield. Epoxide opening with piperazine 15 in refluxing methanol followed by Boc-removal gave 16 in 94% yield. Finally, treatment of piperazine derivative 16 with 3-picolyl chloride in sulfuric acid afforded Indinavir sulfate in 75% yield from epoxide 14 and 56% yield for the overall process (Scheme 24.1).17-22... 

The electrolysis of brine is carried out on a huge scale for the industrial production of chlorine and caustic soda (sodium hydroxide). Because the reduction potential of Na+ is much higher than that of water, the latter substance undergoes decomposition at the cathode, yielding hydrogen gas and OH-. 

Aldoses and ketoses can be reduced to alditols by various agents for which purpose sodium borohydride is very useful. For industrial production of alditols, however, catalytic hydrogenation is applied. Only one product is formed from aldoses, whereas ketoses give rise to two diastereoisomers because of the generation of a new asymmetric center (Fig. 2-26). Sodium borohydride can also be used for reduction of carbonyl groups in polysaccharides. 

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. 

The industrial production of ethylene and propylene oxides was historically dependent on the chlorohydrin process, a multistep procedure that proceeds via the stoichiometric reaction of propylene (or ethylene) with chlorine and water to yield a mixture of chlorohydrin isomers (only one for ethylene) and hydrochloric acid. The epoxide is formed upon reaction of the chlorohydrins with calcium or sodium hydroxide. All the chlorine used in the process eventually ends up as chlorinated organic and inorganic by-products (Equation B2). 

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