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Hydrogen cyanide production

In the evaluation of the regenerative heat exchange option, it is instructive to consider the heat exchange techniques presently employed in the following chemical processes styrene synthesis, steam reforming, and hydrogen cyanide production (Table 1). [Pg.403]

Process design and operation, which are the central and important areas in chemical engineering, have attracted many applications of MOO since the year 2000. In all, there are 35 applications of MOO for process design and operation (Table 2.1). These cover fluidized bed dryer, cyclone separator, a pilot scale venturi scrubber, hydrogen cyanide production, heat exchanger network, grinding, froth floatation circuits, simulated moving bed (SMB) and related separation systems, thermal... [Pg.29]

Process alternatives for hydrogen cyanide production Maximization of economic benefit and minimization of environmental inq)act. A preference-based approach Hoffmann et al. (2001) considered total annualized profit per service unit (TAPPS) and material intensity per service (MIPS) as economic and environmental indicator respectively, while Hoffmann et al. (2004) considered Eco-indicator 99 (E199) for environmental objective as well as uncertainty in model parameters. Hoffmann et al. (2001)... [Pg.31]

Scheme 5.3.2 Hydrogen cyanide production from methane. Scheme 5.3.2 Hydrogen cyanide production from methane.
It is readily oxidized by air to benzoic acid. With aqueous KOH gives benzyl alcohol and benzoic acid. Gives addition products with hydrogen cyanide and sodium hydrogen sulphite. [Pg.54]

To 2 ml. of the ester, add 2--3 drops of a saturated freshly prepared solution of scdium bisulphite. On shaking, a gelatinous precipitate of the bisulphite addition product (D) of the keto form separates, and on standing for 5-10 minutes usually crystallises out. This is a normal reaction of a ketone (see p. 344) hydrogen cyanide adds on similarly to give a cyanhydrin. [Pg.269]

The product of addition of hydrogen cyanide to an aldehyde or a ketone contains both a hydroxyl group and a cyano group bonded to the same carbon Compounds of this type are called cyanohydrins... [Pg.717]

Amm oxida tion, a vapor-phase reaction of hydrocarbon with ammonia and oxygen (air) (eq. 2), can be used to produce hydrogen cyanide (HCN), acrylonitrile, acetonitrile (as a by-product of acrylonitrile manufacture), methacrylonitrile, hen onitrile, and toluinitnles from methane, propylene, butylene, toluene, and xylenes, respectively (4). [Pg.217]

In the early versions, ethylene cyanohydrin was obtained from ethylene chlorohydrin and sodium cyanide. In later versions, ethylene oxide (from the dkect catalytic oxidation of ethylene) reacted with hydrogen cyanide in the presence of a base catalyst to give ethylene cyanohydrin. This was hydrolyzed and converted to acryhc acid and by-product ammonium acid sulfate by treatment with about 85% sulfuric acid. [Pg.155]

Acrylonitrile is combustible and ignites readily, producing toxic combustion products such as hydrogen cyanide, nitrogen oxides, and carbon monoxide. It forms explosive mixtures with air and must be handled in weU-ventilated areas and kept away from any source of ignition, since the vapor can spread to distant ignition sources and flash back. [Pg.185]

Analogously, aldehydes react with ammonia [7664-41-7] or primary amines to form Schiff bases. Subsequent reduction produces a new amine. The addition of hydrogen cyanide [74-90-8] sodium bisulfite [7631-90-5] amines, alcohols, or thiols to the carbonyl group usually requires the presence of a catalyst to assist in reaching the desired equilibrium product. [Pg.471]

Cmde HCl recovered from production of chlorofluorocarbons by hydrofluorination of chlorocarbons contains unique impurities which can be removed by processes described in References 53—62. CICN—CI2 mixtures generated by reaction of hydrogen cyanide and CI2 during the synthesis of (CICN) can be removed from the by-product HCl, by fractional distillation and recycling (see Cyanides) (59). [Pg.446]

Other methods of production iaclude hydrolysis of glycolonittile [107-16 ] with an acid (eg, H PO or H2SO2) having a piC of about 1.5—2.5 at temperatures between 100—150°C glycolonittile produced by reaction of formaldehyde with hydrogen cyanide recovery from sugar juices and hydrolysis of monohalogenated acetic acid. None of these has been commercially and economically attractive. [Pg.516]

Hydrogen Cyanide Process. This process, one of two used for the industrial production of malonates, is based on hydrogen cyanide [74-90-8] and chloroacetic acid [79-11-8]. The intermediate cyanoacetic acid [372-09-8] is esterified in the presence of a large excess of mineral acid and alcohol. [Pg.467]

In the final step the dinitrile is formed from the anti-Markovrukov addition of hydrogen cyanide [74-90-8] at atmospheric pressure and 30—150°C in the hquid phase with a Ni(0) catalyst. The principal by-product, 2-methylglutaronitrile/4j5 j5 4-ti2-, when hydrogenated using a process similar to that for the conversion of ADN to hexamethylenediamine, produces 2-meth5i-l,5-pentanediamine or 2-methylpentamethylenediamine [15520-10-2] (MPMD), which is also used in the manufacture of polyamides as a comonomer. [Pg.232]

Ammonia is consumed in the manufacture of ammonium phosphates and ammonium sulfate by reaction with phosphoric acid and sulfuric acid, respectively. The phosphates may contain ortho- and polyphosphate values. Ammonium sulfate is also a by-product from other ammonia-using industries such as caprolactam (qv) and hydrogen cyanide (see Cyanides). [Pg.358]

Yields based on propylene are 50—75%, and the main by-products are acetonitrile and hydrogen cyanide (96). [Pg.129]

Health nd SMety Factors. The lowest pubhshed human oral toxic dose is 430 mg/kg, causing nervous system disturbances and gastrointestinal symptoms. The LD q (rat, oral) is 750 mg/kg (183). Thiocyanates are destroyed readily by soil bacteria and by biological treatment systems in which the organisms become acclimatized to thiocyanate. Pyrolysis products and combustion products can include toxic hydrogen cyanide, hydrogen sulfide, sulfur oxides, and nitrogen oxides. [Pg.152]


See other pages where Hydrogen cyanide production is mentioned: [Pg.920]    [Pg.215]    [Pg.920]    [Pg.201]    [Pg.206]    [Pg.606]    [Pg.213]    [Pg.182]    [Pg.964]    [Pg.59]    [Pg.920]    [Pg.215]    [Pg.920]    [Pg.201]    [Pg.206]    [Pg.606]    [Pg.213]    [Pg.182]    [Pg.964]    [Pg.59]    [Pg.191]    [Pg.13]    [Pg.51]    [Pg.180]    [Pg.62]    [Pg.428]    [Pg.513]    [Pg.290]    [Pg.298]    [Pg.299]    [Pg.178]    [Pg.251]    [Pg.274]    [Pg.275]    [Pg.242]    [Pg.240]    [Pg.353]    [Pg.135]   
See also in sourсe #XX -- [ Pg.358 ]

See also in sourсe #XX -- [ Pg.204 , Pg.205 , Pg.206 ]

See also in sourсe #XX -- [ Pg.964 ]




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Hydrogen cyanid

Hydrogen cyanide

Hydrogen cyanide industrial production

Methane hydrogen cyanide production

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