Propyne-propadiene mixture

PROPYNE MIXED WITH PROPADIENE or PROPYNE-PROPADIENE MIXTURE... 

PROPYNE MIXED WITH PROPADIENE or PROPYNE-PROPADIENE MIXTURE (59355-75-8) Flammable gas. Violent reaction with strong oxidizers. Forms explosive... 

Synonyms/Trade Names MAPP gas. Methyl acetylene-allene mixture, Propadiene-methyl acetylene. Methyl acetylene-propadiene mixture (stabilized), Propyne-allene mixture, Propyne-propadiene mixture ... 

SYNONYMS mapp gas, methyl acetylene - allene mixture, methyl acetylene - propadi-ene mixture (stabilized), propadiene methyl acetylene, propyne - allene mixture, propyne - pro-padiene mixture. 

METHYL ACETYLENE-PROPADIENE MIXTURE MAPP gas. Methyl acctylcnc>allene mixture. Propyne-allene mixture Strong oxidizers, copper alloys (>67 Cu NA 3.4 11... 

L,2-propadiene, allene, CH2=C = CH2, CjH4. Colourless gas prepared by the electrolysis of potassium itaeonate, or by the action of zinc and alcohol on 1,3-dibromopropane. It is easily isomerized to propyne (methylacetyl-ene), and is produced as a mixture with this substance from some reactions. 

Commercial propyne contains important quantities of propadiene, this mixture not being sensitive to impact. 

A mixture of propyne containing 30% of propadiene under a pressure of 3.5 bar was accidentally brought to 95°C at a spot in the storage cylinder. It then detonated. Commercial propyne becomes dangerous at 3.4 bar and at 20°C. It is lowered to 2.1 bar if the compound is heated to 120°C. Some authors think that the stability of the commercial mixture is close to that of ethylene. 

Considerably more work has been reported on the addition of HCI to allenes.73,76 Bismuth trichloride has frequently been added to catalyze these reactions. 1,2-Propadiene affords mixtures of 2-chloro-l-propene, 2,2-dichloropropane,propyne, and l,3-dichloro-l,3-dimethylcyclobutane.75-77... 

The lithiocarbon C3Li4 reacts with organic and organometallic substrates to give a variety of highly unsaturated derivatives (Scheme 1). With organometallic halides such as trialkylchlorosilanes, the usual products are tetrasubstituted allenes (2). Alkyl halides often give explosions, but the alkyl sulfates produce mixtures of tetraalkyl derivatives of propyne and propadiene (3). 

The C3+-fraction of the C2 /C3+ splitter enters the C3/C4+ splitter that separates propane, propene, propadiene, and propyne from all heavier products. The C3 stream undergoes a selective hydrogenation step in a fixed bed reactor that converts propyne and propadiene mainly into propene. Propene and propane are separated in a very similar way as ethane/ethene. Again, distillation columns with more than 100 trays are applied, making these separation units very costly in investment and energy consumption. The bottom fraction of the C3/C4+ splitter is transferred to C4/C5+ splitter. The C4 fraction leaving this column at the top contains mainly butadiene, isobutene, 1-butene, 2-butene, and butane. The further use of this crack-C4 mixture is described in detail in Section 5.3. 

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