Glycerol from allyl alcohol

By-product acetic acid is obtained chiefly from partial hydrolysis of cellulose acetate [9004-35-7]. Lesser amounts are obtained through the reaction of acetic anhydride and cellulose. Acetylation of saHcyHc acid [69-72-7] produces one mole of acetic acid per mole of product and the oxidation of allyl alcohol using peracetic acid to yield glycerol furnishes by-product acid, but the net yield is low. 

From Allyl Alcohol. The reaction of allyl alcohol [107-18-6] with chlorine and water gives a mixture of glycerol m on ochl orohydrin s consisting of 73% 3-chloropropane-l,2-diol and 27% of 2-chloropropane-l,3-diol (57). In a recycle reaction system in which allyl alcohol is fed as a 4.5—5.5 wt % solution, chlorine is added at a rate of 7—9 moles per hour. The reaction time is about five seconds, the reaction temperature 50—60°C and the recycle ratio is 10—20 1. Under these conditions m on ochl orohydrin s have been obtained in 88% yield with 9% dichlorohydrins (58) (see Allyl ALCOHOL AND DERIVATIVES). 

In the experiments described, a more dilute hydrobromic acid solution may be used, provided that the proportion of sulfuric acid is increased. Aqueous solutions of alcohols may also be used, provided a suitable adjustment is made of the proportion of sulfuric acid. In the allyl alcohol experiment, material was used as obtained from the glycerol-formic acid preparation after one salting-out with potassium carbonate. 

The use of mixtures of glycerol and formic acid for the preparation of allyl derivatives (allyl ch oride and allyl formate) has recently been described by Aschan.2 Allyl alcohol has also been isolated from crude wood alcohol.3 A special method for titrating allyl alcohol has been described.4... 

The production volume of hydrogen peroxide is in hundreds of thousands of tons. It is one of the most widespread and valuable products in modem chemistry. All over the world hydrogen peroxide is widely applied in epoxidation and hydroxylation processes, for example, in glycerol production from allyl alcohol or organic peroxides, which are polymerization and vulcanization initiators. 

Although catalyst B is simpler to prepare than catalyst A, it should not be used if the diol is to be distilled directly from the reaction mixture, since residual sodium chlorate can cause explosions when heated with an organic compound. Hydroxylation of allyl alcohol with catalyst A gave glycerol in 67% yield. ri.t-Cyclohcxaiic-l,2-diol was obtained in 76% yield by hydroxylation of cyclohexene with catalyst B. 

This simplest primary alcohol of the ethylene series, and commonly known as allyl alcohol, is produced from glycerol (glycerin) by a reaction which will be discussed later. It is also produced by the destructive distillation of many organic substances, such as wood, and is therefore found as a constituent of crude wood alcohol. It is a colorless liquid with a strong odor and it boils at 96.6°. It mixes in all proportions with water. By the action of nascent hydrogen, Zn -f H2SO4, it is converted into the corresponding saturated alcohol ... 

A procedure for the preparation of allyl alcohol introduced by B. Tollens (1870) and later improved calls for heating glycerol with three successive portions of formic acid to a temperature of 260° (li days) and recovery of the allyl alcohol from the distillate (46% yield). Glycerol monoformate is formed and suffers pyrolysis to the unsaturated alcohol, carbon dioxide, and water. 

Derivation (1) Oxidation of allyl alcohol or propylene (2) by heating glycerol with magnesium sulfate (3) from propylene with bismuth-phosphorus-mo-lybdenum catalyst. 

Derivation (1) By-product of soap manufacture (2) from propylene and chlorine to form allyl chloride, which is converted to the dichlorohydrin with hypo-chlorous acid this is then saponified to glycerol with caustic solution (3) isomerization of propylene oxide to allyl alcohol, which is reacted with peracetic acid, (the resulting glycidol is hydrolyzed to glycerol) (4) hydrogenation of carbohydrates with nickel catalyst (5) from acrolein and hydrogen peroxide. 

It should be noted that some homogeneous complex catalysts without acids enable the double-dissociation of C-O bonds in polyols such as 1,2-hexanediol to n-hexane with Ru complex/H2 [18,19] and glycerol to allyl alcohol over CHsReOs/ alcohol [20]. Different mechanisms from those shown in Fig. 2 have been proposed for these systems, which are discussed in another chapter of this volume by Boucher-Jacobs and Nicholas. 

Allyl alcohol and its derivatives have been widely employed as intermediates in chemical synthesis and as monomers in polymerization. Although allyl compounds exist widely in nature, they are prepared synthetically for large commercial volumes. Early syntheses of allyl alcohol was based on the preparation of allyl halide intermediates from glycerol or propylene. There are two more recent commercial routes to produce allyl alcohol 1) oxidizing propylene to acrolein and then reacting it with a secondary alcohol, and 2) isomerizing propylene oxide. The route 1) results in a mixture of allyl alcohol and a ketone. The route 2) is preferred to produce a high purity allyl alcohol. 

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