Propylene dibromide

Allyl Bromide. Introduce into a 1-litre three-necked flask 250 g. (169 ml.) of 48 per cent, hydrobromic acid and then 75 g. (40-5 ml.) of concentrated sulphuric acid in portions, with shaking Anally add 58 g. (68 ml.) of pure allyl alcohol (Section 111,140). Fit the flask with a separatory funnel, a mechanical stirrer and an efficient condenser (preferably of the double surface type) set for downward distillation connect the flask to the condenser by a wide (6-8 mm.) bent tube. Place 75 g. (40 5 ml.) of concentrated sulphuric acid in the separatory funnel, set the stirrer in motion, and allow the acid to flow slowly into the warm solution. The allyl bromide will distil over (< 30 minutes). Wash the distillate with 5 per cent, sodium carbonate solution, followed by water, dry over anhydrous calcium chloride, and distil from a Claisen flask with a fractionating side arm or through a short column. The yield of allyl bromide, b.p. 69-72°, is 112 g. There is a small high-boiling fraction containing propylene dibromide. 

The derivatives of ethylene dibromide, propylene dibromide, trimethylene dibromide and tao-butylene dibromide melt at 260°, 232°, 229° and 223° respectively. 

By-products include propylene dibromide, bis-(bromopropyl) ether, propylene glycol, and propionic acid. Bromide losses are to the brominated organics and bromate formation. Current efficiency is a function of ceU design and losses to bromate. Energy consumption decreases with an increase in electrolyte concentration and a decrease in current density. Space—time yield increases with current density. See Table 5 for performance data (see... 

Propylene dibromide, d92 sec-Propylene chlorohydrin, c213 Propylenediamine, pi 92 Propylene glycol, pi94 Propylene glycol isopropyl ether, i86 Propylene glycol monomethyl ether, m95 Propylene glycol monophenyl ether, p73... 

Propyl Alcohof Propylene Dibromide Propylene Dichloride Propylene Glycol Methyl Ether... 

Sodium Sulfite 7783-28-0 Diammonium Phosphate Propylene Dibromide... 

Benzaldehyde Diisopropylbenzene Methyl Ethyl Ketone Propylene DIbromide... 

D5. A column with 29 equilibrium stages and a partial reboiler is being operated at total reflux to separate a mixture of ethylene dibromide and propylene dibromide. Ethylene dibromide is more volatile, and the relative volatility is constant at a value of 1.30. We are measuring a distillate concentration that is 98.4 mol% ethylene dibromide. The column has a total condenser and saturated liquid reflux, and CMO can be assumed. Use the Fenske equation to predict the bottoms conposition. 

Zawidski s Results.—The strongest evidence is afforded by two pairs of liquids, ethylene and propylene dibromides and benzene and ethylene dichloride, investigated by Zawidski (9). 

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