Hydrogen cyanide, from decomposition

Using three deuterium-substituted anilines, an average isotope effect of 5.6 was found for loss of hydrogen cyanide from metastable aniline ions as found previously, some degree of hydrogen randomisation accompanied the decomposition [12]. In contrast, the metastable 2-,... 

In the BMA process, methane (natural gas) and ammonia are reacted without air being present (44). The reaction is carried out in tubes that are heated externally to supply the endothermic heat of reaction very similar to a reformer. Yield from ammonia and methane is above 90%. The off-gas from the converter contains more than 20 mol % hydrogen cyanide, about 70 mol % hydrogen, 3 mol % ammonia, 1 mol % methane, and about 1 mol % nitrogen from ammonia decomposition. 

Methylsuccinic acid has been prepared by the pyrolysis of tartaric acid from 1,2-dibromopropane or allyl halides by the action of potassium cyanide followed by hydrolysis by reduction of itaconic, citraconic, and mesaconic acids by hydrolysis of ketovalerolactonecarboxylic acid by decarboxylation of 1,1,2-propane tricarboxylic acid by oxidation of /3-methylcyclo-hexanone by fusion of gamboge with alkali by hydrog. nation and condensation of sodium lactate over nickel oxide from acetoacetic ester by successive alkylation with a methyl halide and a monohaloacetic ester by hydrolysis of oi-methyl-o -oxalosuccinic ester or a-methyl-a -acetosuccinic ester by action of hot, concentrated potassium hydroxide upon methyl-succinaldehyde dioxime from the ammonium salt of a-methyl-butyric acid by oxidation with. hydrogen peroxide from /9-methyllevulinic acid by oxidation with dilute nitric acid or hypobromite from /J-methyladipic acid and from the decomposition products of glyceric acid and pyruvic acid. The method described above is a modification of that of Higginbotham and Lapworth. ... 

Presence of 25% of the organometallic salt (ferrocenium reineckate) considerably increases the rate of thermal decomposition of the perchlorate, involving hydrogen cyanide arising from the thiocyanato groups. 

Benzoyl cyanide can be prepared by the thermal decomposition of cj-isonitrosoacetophenone,5 from silver cyanide and benzoyl chloride,3 from anhydrous hydrogen cyanide and benzoyl chloride in the presence of pyridine,4 and by the thermal decomposition of phenylchloronitrocyanomethane.6 6... 

Many allelochemicals are decomposed in soil, either abiotically (37) or by microorganisms (95-100). Obviously, the attainment of active concentrations of allelochemicals in soil depends on the relative rates of addition and inactivation. It is important to understand also that microbial decomposition of allelochemicals does not necessarily result in a decrease in allelopathic activity. In fact, the reverse may be true. Hydrojuglone is oxidized in soil to juglone, a quinone that is inhibitory to some species at a 10 ° M concentration (101). Isoflavonoids produced by red clover are decomposed to even more toxic phenolic compounds (95) and to repeat, amygdalin from peach roots is changed to hydrogen cyanide and benzaldehyde which cause the peach replant problem (88), and phlorizin from apple roots is decomposed to several phenolic compounds that appear to be responsible for the apple replant problem (100). 

Cyanohydrins should be stabilized with acid to pH 3-4 to prevent decomposition 10 hydrogen cyanide and carbonyl compound. When cyanohydrins are shipped, steel drums, carboys, tank cars, and barges are used. In general, cyanohydrins are combustible liquids and many decompose upon heating. They should be stored in a cool, dry place, preferably outside and separated from other storage. Containers should be protected against physical damage. 

The addition of alkaline chemicals, water, and/or heal may promote self-polyincrizalion and decomposition of hydrogen cyanide. The self-polj ineriaUion reaction is exothermic, and the heat released will promote further polymerization. The heat generation will also result in the decomposition of hydrogen cyanide into anunonia and formate. Tlie pressure rise from polymerization or decomposition reactions can become explosive. Small amounts of acid, such as sulfuric or phosphoric, will help to stabilize tlie hydrogen cyanide against polymerization. 

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