Sodium hydroxide alkalizer

There have been many investigations on the oxidation of sodium hydroxide-alkalized cellulose for the preparation of rayon and lacquers, for the oxygen bleaching of fiber, and for the oxygen pulping of wood chips. 

A solution of 27.2 parts of 4-diisopropvlamino-2-phenvl-2-(2-pvridvl)butyronitrile in 200 parts of concentrated sulfuric acid is heated on a steam bath for 4 hours and then poured onto ice. The resultant mixture is alkalized with ION sodium hydroxide, and the pH is adjusted to 6 by the addition of acetic acid. The solution is washed once with benzene before it is alkalized again with ION sodium hydroxide solution. The resultant mixture is extracted with benzene, and the solvent is evaporated from the benzene extract. The resultant residue is dissolved in ethanol and the alcohol solution is treated with charcoal and filtered. Evaporation of the solvent leaves a residue which is recrystallized from hexane to give 4-diisopropvlamino-2-phenvl-2-(2-Pvridvl)butyramide melting at about 94.5°-95°C. 

Ethyl-2-methyl-3-(10,11) -dihydro-5H-dibenzo [a,d] cycloheptene-5-ylidene)-1 -pyrrolinium iodide (4.7 g) was dissolved in 7 cc of methanol. To this solution there were added 1.4 g of sodium boron hydride within about 80 minutes with stirring and stirring of the solution was continued for two hours to complete the reaction. The reaction mixture was acidified with 10% aqueous hydrochloric acid solution and then the methanol was distilled off. The residual solution was alkalized with 20% aqueous sodium hydroxide solution and extracted with ether. The ether layer was dried over magnesium sulfate and the ether was distilled off. The resulting residue was further distilled under reduced pressure to yield 2.0 g of 1-ethyl-2-methyl-3-(10,11 ) dihydro-5H-dibenzo[a,d]cycloheptene-5-ylidene)pyrrolidine (boiling point 167°C/4 mm Hg.). 

The formyl derivative is then hydrolyzed by refluxing with 50% sulfuric acid for about 4 hours, after which the hydrolysate is extracted with ether to remove the acid-insoluble material and the aqueous solution made strongly alkaline with any suitable alkalizing agent, for example, sodium hydroxide, to liberate the amine. 

Phosphate need not be used in boilers where hardness can be eliminated from the FW at all times. Its use is not recommended for boilers that may exhibit severe hideout (see the section on coordinated phosphate treatment). In these circumstances, sodium hydroxide is the preferred alkalizing agent and should be dosed to a maximum of 1.5x the sodium chloride content. 

Isolation of the products is accomplished by decomposition with sodium potassium tartrate [576], by water and dilute sodium hydroxide [727], or by successive treatment with 6n sulfuric acid followed by alkalization with potassium hydroxide [787]. 

To a solution of 3.65 g (0.03mol) of p-aminobenzylamine in 60g (0.45mol) of 50% aqueous hypophosphorous acid placed in a 200 ml flask 50 ml of water is added and the mixture is cooled to 5°. With stirring, a solution of 2.3 g (0.033 mol) of sodium nitrite in 10 ml of water is added dropwise over a period of 10-15 minutes. The mixture is stirred for a half-hour at 5° and allowed to come to room temperature and to stand for about 4 hours. After strong alkalization with sodium hydroxide the product is obtained by continuous extraction with ether, drying of the extract with potassium hydroxide, and distillation. The yield of benzylamine is 2.67 g (84%), b.p. 181-183°. 

From 4.1 parts DL-4-(aminomethyl)-l-[2-(l,4-benzodioxanyl)methyl]-4-phenylpiperidine dihydrochloride, the free base is liberated in the usual manner and extracted with chloroform. The organic layer is separated, dried and evaporated. The DL-4-(aminomethyl)-l-[2-(l,4-benzodioxanyl)methyl]-4-phenylpiperidine obtained is dissolved in 128 parts anhydrous chloroform. This solution is cooled to 5°C and there is added dropwise a solution of 1.6 parts acetylchloride in 7 parts anhydrous chloroform (exothermic reaction). The reaction mixture is stirred over night at room temperature and then alkalized with about 25 parts sodium hydroxide 20% at a temperature of 20°C. The aqueous layer is separated and extracted twice with chloroform. The combined organic layers are washed with water, dried over magnesium sulfate, filtered and evaporated. The oily residue is dissolved in a mixture of 40 parts acetone and 20 parts diisopropyl ether and evaporated again. The solid residue is triturated in diisopropylether, yielding DL-4-(N-acetylaminomethyl)-l-[2-(l,4-benzodioxanyl)-methyl]-4-phenylpiperidine melting point 140°-141.1°C, as a white microcrystalline powder. 

A mixture of 4-[4-(diphenylmethyl)-l-piperazinylmethyl]-Nl-ethyl-l,2-benzenediamine and acetic acid is stirred at room temperature till all solid enters solution. Then there are added pentyl ethanimidate hydrochloride and stirring is continued first for 1 h at room temperature and further for 1 h at reflux. The reaction mixture is evaporated and the residue is stirred in water. The whole is alkalized with a sodium hydroxide solution and the product is extracted with dichloromethane. The extract is dried, filtered and evaporated. The residue is purified by column-chromatography over silica gel using a mixture of trichloromethane and methanol as eluent. The pure fractions are collected and the eluent is evaporated. The product is filtered off and dried, yielding 5-[4-(diphenylmethyl)-l-piperazinylmethyl]-l-ethyl-2-butyl-lH-benzimidazole melting point 124.8°C (crystallized from 4-methyl-2-pentanone). 

A mixture of 30 parts of 4-[4-(4-methoxyphenyl)-l-piperazinyl]benzenamine and 300 parts of a hydrobromic acid solution 48% in water is stirred and refluxed for 10 days. The reaction mixture is evaporated and the residue is alkalized with sodium hydroxide. The mixture is filtered and the filtrate is acidified with acetic acid. The precipitated product is filtered off and crystallized from 1,4-dioxane, yielding 12 parts (44%) of 2,4-dihydro-4- 4-[4-(4-hydroxyphenyl)-l-piperazinyl]phenyl -2-(l-methylpropyl)-3H-l,2,4-triazol-3-one. 

The mixture of 1.4 kg o-nitrophenol, 2.1 kg o-aminophenol, 6 kg glycerine (d = 1.26) and 5 kg sulfuric acid (d = 1.848) was heated at reflux to temperature 130°-140°C. This temperature was kept for 1.5 hours. The obtained oxyquinoline precipitated, the liquid was removed with water-steam distillation. The residue was diluted with water and alkalized with sodium hydroxide and sodium carbonate to the strong alkaline reaction. The repeated distillation with water steam gave the oil, which hardened as the long needles by cooling. MP 75°-76°C recrystallized from diluted ethanol. 

The residual solution was alkalized with 20% aqueous sodium hydroxide solution and extracted with ether. The ether layer was dried over magnesium sulfate and the ether was distilled off. The resulting residue was further distilled under reduced pressure to yield 2.0 g of l-ethyl-2-methyl-3-(10,ll)-dihydro-5H-dibenzo[a,d]cycloheptene-5-ylidene)pyrrolidine (boiling point 167°C/4 mm Hg.). 

The alkalized paper was soaked in the Kymene/sorbitol solutions for one hour, hung to drain, air dried flat on plastic screen, and then oven dried at 100°C for two hours. Kymene has a pH of 4.6-4.9. To avoid having the Kymene/sorbitol solutions reacidify the paper, they were brought to pH 7 with dilute sodium hydroxide before use. 

In this work, the influence of the conditions of aluminium hydroxide precipitation on interfacial surface development was analyzed, and batch-scale experiments on active aiuminium hydroxide (AAH) formation were conducted. Aluminium hydroxide precipitates were produced by alkalization of aluminium sulfate solutions using sodium hydroxide. 

Potassium cyanide solution (POISON) after first alkalizing the test solution with sodium hydroxide and adding potassium cyanide, thiocyanate ions are formed on boiling ... 

H. Yokota, The mechanism of cellulose alkalization in the isopropyl alcohol-water sodium hydroxide-cellulose system, J. Appl. Polym. Sci., 30 (1985) 263-277. 

Cyanides Water samples to determine cyanide must be kept chilled and dark for transport. They should be alkalized with sodium hydroxide solution (1 molar) on site and adjusted to a pH of around 8. 

Samples taken from water containing no oxidizing agents are first neutralized against phenolphthalein by adding 1 m hydrochloric acid or 1 m sodium hydroxide, and then slightly alkalized by adding 1 ml of 1 m sodium hydroxide for every litre of the sample. 

Sodium, potassium and calcium salts of mono and polyphosphoric acids, incl. such salts when alkalized with sodium carbonate, sodium hydroxide or sodium silicate... 

Figure 21.17 Mercury cell used In the chlor-alkall process. The cathode contains mercury. The sodium-mercury amalgam Is treated with water outside the cell to produce sodium hydroxide and hydrogen gas.

Chlor-alkall production — With a 63% production volume of the total world chlorine capacity of about 43.4 million tons (in 1998), the chlor-alkali (or chlorine-caustic) industry is one of the largest electrochemical technologies in the world. Chlorine, CI2, with its main co-product sodium hydroxide, NaOH, has been produced on industrial scale for more than a century by -> electrolysis of brine, a saturated solution of sodium chloride ( alkali chloride electrolysis). Today, they are among the top ten chemicals produced in the world. Sodium chlorate (NaClOs) and sodium hypochlorite (NaOCl, bleach ) are important side products of the... 

The substance (1—2 mg) is melted with a crystal of phenol. To the cooled melt a few drops of concentrated sulfuric acid are added. A dark, cherry-red color is formed. The reaction mixture is diluted with 2 ml of water and alkalized with a few drops of sodium hydroxide solution the solution turns green, blue, and sometimes even violet. 

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