Whiting compounds

This product is sufficiently pure for the preparation of phenylacetic acid and its ethyl ester, but it contains some benzyl tso-cyanide and usually develops an appreciable colour on standing. The following procedure removes the iso-cyanide and gives a stable water-white compound. Shake the once-distilled benzyl cyanide vigorously for 5 minutes with an equal volume of warm (60°) 60 per cent, sulphuric acid (prepared by adding 55 ml. of concentrated sulphuric acid to 100 ml. of water). Separate the benzyl cyanide, wash it with an equal volume of sa+urated sodium bicarbonate solution and then with an equal volume of half-saturated sodium chloride solution- Dry with anhydrous magnesium sulphate and distil under reduced pressure. The loss in washing is very small (compare n-Butyl Cyanide, Section 111,113, in which concentrated hydrochloric acid is employed). 

Since acetal resins are degraded by ultra violet light, additives may be included to improve the resistance of the polymer. Carbon black is effective but as in the case of polyethylene it must be well dispersed in the polymer. The finer the particle size the better the ultra violet stability of the polymer but the poorer the heat stability. About 1.5% is generally recommended. For white compounds and those with pastel colours titanium dioxide is as good in polyacetals as most transparent ultraviolet absorbers, such as the benzophenone derivatives and other materials discussed in Chapter 7. Such ultraviolet absorbers may be used for compounds that are neither black, white nor pastel shade in colour. 

Moisture must be removed from natural gas to reduce corrosion problems and to prevent hydrate formation. Hydrates are solid white compounds formed from a physical-chemical reaction between hydrocarbons and water under the high pressures and low temperatures used to transport natural gas via pipeline. Hydrates reduce pipeline efficiency. 

The most recent major expln in a US TNT plant occurred in May 1974 at the Radford Army Ammunition Plant. The accident completely destroyed one of the three continuous nitration lines at the plant. According to the AMC News, Sept 1974, the investigation board reported that an operator inadvertently introduced a 5 to 6-foot rubber hose to clean out unwanted material that had collected in a transfer line leading to the nitrator, when the hose was pulled from his hands into the nitrator. This resulted in a rapid temp rise and subsequent explosion. The hose was commonly used in this manner . The material causing the blockage in the transfer line was believed to be an oxidation product of TNT, 2,2 -dicarboxy-3,3, 5,5,-tetra-nitroazoxybenzene, also referred to as White Compound. The introduction of the rubber hose caused a rapid, exothermic oxidation reaction between the hose material and the mixed acid present. The heat generated by this reaction caused a local acceleration of the normal nitration/oxidation reactions which occur in the nitrator until a critical temp was reached, at which point rapid oxidation of DNT/TNT proceeded as a runaway reaction, igniting the material present in the vessel. 

Poly(carbon monofluoride) is a white compound, often reported to be explosive and unstable but found in our research results to be stable in air at temperatures up to at least 600°C. In fact, poly(carbon monofluoride) is the most thermally stable fluoropolymer known. It decomposes upon heating at 800°C or under a high vacuum at 580°C to form a series of polyolefinic fluorocarbons. 19 The compounds with compositions in the range of CFo s to CFos are nearly black. The CFos to CF0.95 compounds become gray and the CF095 to CFuj... 

Bismuth trichloride also unites with quinoline and pyridine. Quino-lino-bismuth chloride, [Bi(C9H7N)]Cl3, is obtained as a white crystalline mass on mixing the chloride with the base. This derivative is only slowly decomposed by water and is not deliquescent.3 Bismuth chloride and pyridine form a white compound of composition BiCl3.l-5(CsH5N) or 2BiCl3.3(C5H5N) on adding pyridine to an ethereal solution of bismuth chloride,4 or it may be formed from an acetone solution of the chloride and excess of pyridine.3 It is a white crystalline powder, fairly stable towards water, and only attacked slowly by hydrochloric acid. Aqueous sodium hydroxide quickly decomposes the additive compound. 

WhC "White Compound (1, di-carboxyl,4,6,8-tecranitro-phe na zine-N- oxide)... 

White Compound. See under TNT article in Vol 9 in the following sections Preparation , T241-L Purification , T244, Table 1 Chemical Reactions and Derivatives , T248-R and in Vol 8, N84-R... 

When sulphide of hydrogen gas is passed to saturation through a solution of protoxide of meroury, the white compound which appears at an early Btage of the operation is destroyed, and the black precipitate then consists solely of mercuric sulphide, which, when collected, dried, and heated in a retort, yields a fine crystalline sublimate of cinnabar. These two bodies, therefore, the black and the red, are allotropio modifications of one substance, Hg S. 

The Detection and Estimation of Carbon Disulphide.—Carbon disulphide may be detected by means of the red, crystalline compound which it forms with triethylphosphine 3 and the white compound with phenylhydrazine.4 Minute quantities can also be detected by producing one of the dithiotrimercuric salts of the type HgX2.2HgS, which form characteristic crystalline precipitates when dilute aqueous solutions of mercuric salts are heated on a water-bath with carbon disulphide.5... 

With a solution of selenium dioxide in uoamyl alcohol, ammonia throws down a white compound, which has been described as ammonium amylselenite, NH4.C5Hu.Se03. The reaction may be represented thus ... 

Most known 1,2,4-triazines and 1,2,4-benzotriazines are yellow, orange or white compounds, usually crystalline at room temperature. They are mostly stable at room temperature and can be distilled under reduced pressure or recrystallized without decomposition. 

In binary combination with oxygen, however, only one simple compound has been isolated, iodine pc mo side. l>Os, a white compound. The yellow hOi prepared Irom sulfunc and iodic acids, is considered to be made up ol 3+ and 5- - iodine, and the structure iodvl iodatc. tier ) (IOv ). is assigned to it. in which Ihc trivalcni state is stabilized by the acid radical. Similarly, yellow letraiodinc enneaoxidc. LO>i. is considered tvi have the structure il1 ) fIO> 15. in which again the trivalcni stale is siahili/ed hy the acid radicals. 

When hydrates are heated, the water is driven off. If you heat blue crystals of CuS04 5 H20 above 350°C, for example, you ll observe formation of anhydrous copper sulfate, CuS04, a white compound (Figure 14.13). 

According to E. Scandola, when hydrazine is added drop by drop to finely granulated sodium suspended in ether, and then heated on a water-bath with a reflux condenser, a white substance is formed which explodes in air. If left in contact with the ether, it loses its explosive property. The white compound does not act on silver nitrate in ammoniacal soln. Its structure is supposed to correspond with sodium triimide or sodium hydrazide ... 

The expln mentioned above occurred during faulty manual removal of white compound , an insoluble TNT oxidation by-product, which has periodically coated the nitrator cooling coils (the chemical structure and mode of formation of this material are given under the section on Chemical Reactions and Derivatives ). It was found (Ref 21) that its formation resulted from high carry-back of TNT oxidation products from one of the nitrators in stage 3 to stage 2. This again pointed to the desirability of cleaner separation of acid and nitrobody, since white compd deposition was not a problem in plants where better separation occurred... 

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