Caustic iodides

The iodine is extracted from the activated carbon using hot caustic soda. The product obtained is an iodate—iodide solution, according to the following reaction ... 

A high yield chemical pulp, eg, 52—53% bleached yield from softwoods, can be obtained, but strength properties ate inferior to those obtained from the kraft process. If a protector, eg, potassium iodide, is added, an additional 2—3% yield is obtained, as is an improvement in all strength properties. The gas penetration problem can be minimized if ftbetization is accompHshed before treatment with oxygen. Oxygen treatment of virtually all types of semichemical and mechanical pulps has been explored (55). Caustic, sodium bicarbonate, and sodium carbonate have been used as the source of base (56,57). In all cases, the replacement of the kraft by these other processes has not been justified over the alternative of pollution abatement procedures. 

Reaction.—A delicate test for ethyl alcohol is the lodofornt reaction. Pour a few drops of alcohol into a test-tube and add about 5 c.c of a solution of iodine in potassium iodide, and then dilute caustic soda solution until the iodine colour vanishes. Shake up and narm very gently to about 6o°. If no turbidity 01 precipitate appears at once, set the test-tube aside for a time. Yellow crystals of iodoform will ultimately deposit, which have a peculiar odoui, and a characteiistic star shape nhen viewed under the microscope. The same reaction is given with... 

The diphenylurethane melts at 107° to 108°. By treatment with methyl iodide in the presence of caustic alkali, eugenol is converted into methyl-eugenol, which is characterised by its monobromo derivative melting at 79° to 80°. 

Dobbin s reagent analychem A mercuric chloride-potassium iodide reagent used to test for caustic alkalies in soap. dab-anz re a- ant ... 

In the ion-exchange method, brine solution is passed through an anion-exchange resin. Iodide (and polyiodide) anions from the solution adsorb onto the resin from which they are desorbed by treatment with caustic soda solution. The resin is treated with sodium chloride solution to regenerate its activity for reuse. The iodide solution (also rich in iodate, IO3 ions) is acidified with sulfuric acid. The acid solution is oxidized to precipitate out iodine. Iodine is purified by sublimation. 

In caustic soda or caustic potash solution, mercury(TI) iodide forms complex salts, Na2Hgl4 and K2Hgl4, respectively. Alkaline solution of this complex in excess potassium hydroxide is known as Nessler s reagent, used to analyze ammonia. The reaction of Nessler s reagent with ammonia may be written as ... 

Finally, it being established that (he solution contains mercury, the identification of it, as the bichloride, may be easily effected by solutions of nitrate of silver, caustic ammonia, iodide of potassium, and protocbloride of tin. 

Methyl hexyl carbinol may be made in a pure state by the action of methyl magnesium iodide upon heptaldehyde,1 but it is more easily and cheaply obtained in a state of satisfactory purity for most purposes by the heating of castor oil with sodium hydroxide.2 This gives sodium ricinoleate which upon fusion with caustic soda yields methyl hexyl carbinol. Other methods of theoretical interest have also appeared the product may be prepared by the chlorination and subsequent hydrolysis of petroleum octane 3 by the distillation of certain rarer oils with sodium hydroxide.4... 

It is reported that trimethylamine in combination occurs in large amounts in beet-root residues 2 and can be obtained from them by the action of caustic soda it occurs also in herring brine.3 From both of these sources, however, the substance is obtained in an impure state and can be purified only by rather tedious methods. This is indicated by the fact that trimethylamine has always been an expensive substance. Synthetic methods for its production are by the action of methyl iodide on ammonia 4 by the distillation of tetramethylammo-nium hydroxide 6 by the action of magnesium nitride upon methyl alcohol 6 by the action of zinc upon trimethyloxy-ammonium halides 7 by the action of formaldehyde upon ammonium chloride under pressure 8 by the action of ammonium chloride upon paraformaldehyde.9 Of these syn-... 

Methyl iodide combines at ordinary temperatures to form a meth-iodide, having the constitution shown below. This crystallises from alcohol as leaflets and from water as needles, M.pt. 197° C. When warmed with caustic alkalis it is decomposed in a similar manner to thioantipyrine ... 

Trimethylplatinic iodide, (CH3)3PtI.—Chloroplatinic acid is used in the preparation, and in order that the method may be successful the acid must be pure. It is heated at 200° C. at atmospheric pressure in a distilling flask placed in a metal-bath the water and hydrochloric acid evolved are absorbed by suction through a Woulfe s bottle containing solid caustic potash. After several hours the acid remaining is nearly pure. It is further treated with anhydrous ether until part... 

General Procedure.—Dissolve 0-2—0-5 gm. of the compound to be estimated in 200 c.cs. of water, using a slight excess of hydrochloric acid for amines or a similar excess of caustic soda in the case of phenols, carboxylic- and sulphonic-acids. To the solution thus prepared 10 c.cs. of a 20% solution of potassium bromide and 5—10 c.cs. of concentrated hydrochloric acid are added the mixture is brought to the required temperature and N/5 bromate solution run in slowly until a sample withdrawn gives a reaction on starch-iodide paper. The presence of free bromine should be again tested for after 5 minutes. 

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