Solution of Soda

In 1990, appioximately 66,000 metric tons of alumina trihydiate [12252-70-9] AI2O2 3H20, the most widely used flame retardant, was used to inhibit the flammabihty of plastics processed at low temperatures. Alumina trihydrate is manufactured from either bauxite ore or recovered aluminum by either the Bayer or sinter processes (25). In the Bayer process, the bauxite ore is digested in a caustic solution, then filtered to remove siUcate, titanate, and iron impurities. The alumina trihydrate is recovered from the filtered solution by precipitation. In the sinter process the aluminum is leached from the ore using a solution of soda and lime from which pure alumina trihydrate is recovered (see Aluminum compounds). 

Vanadium usually is recovered from its ores by one of two processes, (1) leaching raw mineral with hot dilute sulfuric acid, and (2) roasting ore with common salt to convert vanadium into water soluble sodium vanadates. In the sulfuric acid leaching process, vanadium is extracted from acid leach liquors by solvent extraction with an aliphatic amine or an alkyl phosphoric acid in kerosene. The organic solvent extract then is treated with an aqueous solution of ammonia in the presence of ammonium chloride to convert vanadium into ammonium metavanadate. Alternatively, the organic extract is treated with dilute sulfuric acid or an aqueous solution of soda ash under controlled conditions of pH. Vanadium is precipitated from this solution as a red cake of sodium polyvanadate. 

Or a solution of soda may be first saturated with sulphur by boiling, and sulphurous acid may then be passed through this menstruum, when hyposulphite of soda is formed. In cither case the solution obtained is rapidly evaporated to a sirupy consistence and then act to repose, when the hyposulphite separates in large colorless crystals. 

The benzhydrylthioacetyl chloride in 100 ml of methylene chloride was added drop by drop to 35 ml of ammonia in 40 ml of water. Once the addition is complete, the organic phase is washed with a dilute solution of soda and dried over Na2S04, the solvent is evaporated and the residue is taken up in diisopropyl ether, the benzhydrylthioacetamide is crystallised. 16.8 g of product (yield 86%) are obtained. Melting point 110°C. 

There are several techniques for obtaining hydroxyorganosilanes. These techniques generally amount to the hydrolysis of halogen-, alkoxy-, acy-loxy-, amino- and hydride substituted organosilanes with water, as well as aqueous solutions of soda or alkali. The hydrolysis proceeds thus ... 

The temperature during hydrolytic condensation does not exceed 50 °C it is maintained with salt solution (-15 °C) fed into heat exchanger 4 and hydrolyser jacket 5. The mixture of hydrolysate and hydrochloric acid is continuously sent through the hydraulic gate into the middle part of apparatus 6, where it is separated. The top layer, the product of dimethyldichlo-rosilane hydrolytic condensation, continuously enters receptacle 7. From there it is vacuum-loaded into the reactor (not shown in the diagram) to be neutralised with a 15% solution of soda ash. The bottom layer, 27% hydrochloric acid, is poured into receptacle 8. 

Many methods are used to manufacture synthetic borax. First of all it is possible to manufacture borax if boric acid is gradually introduced into a solution of soda at 90 to 100 °C. After settling and separating insoluble substances by filtration, the solution is cooled in a crystallizer, in order to separate the crystals which are finally centrifuged. The mother liquor is used to dissolve new charges of soda ash. 

X) grams, of p-nitrotoluene is sulfonated exactly like nitrobenzene (page 120), and the product is isolated as the sodium salt. The press cake is dissolved at 50°C. in a solution of soda ash in 500 cc. water. About 50 grams of soda ash is required, provided that the material has been pressed out adequately. The solution is filtered to remove some iron oxide which is almost always present, and diluted to 2 liters. 

Materials which have been exposed to phosgene may be decontaminated by exposure to air and, if necessary, washing with a io% solution of soda. ... 

By means of an aspirator, a known volume of the gas mixture to be tested (2-5 litres in 4-10 minutes) is passed through 10 ml. of an aqueous alcoholic solution of soda prepared in the following way ... 

LYE sometimes refers to solutions of soda ash or potash. It is also used for solutions of CAUSTIC SODA sodium hydroxide) and CAUSTIC POTASH (potassium hydroxide), prepared by mixing milk of lime with soda ash or potash. This mixing produces a solution of caustic soda, or caustic potash, and a limestone precipitate. A medieval recipe for caustic soda crystals calls for 1 part each of slaked lime and soda ash with 7 parts water, boiled until the volume is halved, filtered and decanted 10 times then evapouiated. 

Derivation Principally by treating a saturated solution of soda ash with carbon dioxide to precipitate the less soluble bicarbonate also by purifying the crude product from the Solvay process. 

To Prevent Sediment in Preparations of Peruvian Bark. The formation of a sediment in this and other simple preparations of Peruvian bark may be avoided by displacing or digesting its powder first with a solution of soda which wul extract the tanniu, kinovin, Ac. after waging off the last traces of the alkali by means of water, the alcoholic or vinous tincture may then be prepared as usual, and will remain clear, because free from the principles extracted by the alkaline solution. The alkaloids of the bark do not dissolve in weak mineral alkalies,... 

In order to obviate the inconvenience of the production of sulphuretted hydrogen, the gas is collected in a solution of soda, or it is burned at the end of a glass tube connected with the vessel where the reaction takes place. If a burning alcohol lamp be placed at the end of the tube, the combustion of the gas will not be arrested, even... 

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