Method for hydrolyzing alpha-chlorinated toluene compounds
The current invention provides and improved method for hydrolyzing alpha-chlorinated toluene compounds comprising the steps of:—providing an alpha-chlorinated toluene compound of formula (I) wherein at least one of R 1 , R 2 and R 3 is CI and wherein (R a ) n designates that the benzene nucleus may have one or more substituents which may be same or different and are selected from the group consisting of H, CI, Br and —C m H 2m+1 , n being 0 or an integer from 1 to 5, and m being an integer, preferably from 1 to 6,—hydrolyzing said compound with water in the presence of a metal oxide.
1. A method for hydrolyzing alpha-chlorinated toluene compounds comprising the steps of:
providing an alpha-chlorinated toluene compound of formula (I):
wherein a single group of R 1 , R 2 and R 3 is Cl and the remaining R1, R2, and R3 groups are hydrogen, and wherein (R a ) n designates that the benzene nucleus may have one or more substituents which may be same or different and are selected from the group consisting of H, Cl, Br and —C m H 2m+1 , n being 0 or an integer from 1 to 5, and m being an integer, preferably from 1 to 6,
hydrolyzing said compound with water in the presence of a metal oxide, wherein the molar ratio of metal oxide to alpha-chlorinated toluene compound is from 0.5 to 1.5;
wherein the hydrolysis is carried out at a temperature in the range of 70° C. to 180° C., with the proviso that above 100° C. the reaction is carried out under pressure which pressure is at least equal to the vapor pressure of the reaction mixture; and wherein the molar ratio of alpha-chlorinated toluene compounds to water is from 1/10 to 1/50, thereby providing hydrolyzed alpha-chlorinated toluene compound.
2. The method according to claim 1 , wherein the metal oxide is selected from the group consisting of iron oxides, cupper oxides, aluminum oxides and mixtures thereof.
3. The method according to claim 1 , wherein the metal oxide is FeO, Fe 2 O 3 , Fe 3 O 4 or mixtures thereof.
4. The method according to claim 1 , wherein the metal oxide is FeO.
5. The method according to claim 1 , wherein the alpha-chlorinated toluene compound is benzyl chloride.
6. The method according to claim 1 , wherein the hydrolysis is carried out at a pressure in the range of 1 to 10 bars.
7. The method according to claim 6 , wherein the resulting product of hydrolysis is benzyl alcohol.
8. The method according to claim 7 , wherein an aqueous metal chloride side stream is separated from the hydrolysed compound.
9. The method according to claim 8 , wherein FeCl 2 in the separated metal chloride side stream is converted into FeCl 3 ; by adding chlorine gas to the side stream or by oxy-chlorinating the side stream with HCl.
10. The method according to claim 9 , wherein the aqueous FeCl 3 is transferred to a storage unit for use in water treatment.
11. The method according to claim 1 , without the addition of an organic solvent for the extraction of the hydrolyzed compound.
12. The method according to claim 1 , with a conversion of alpha-chlorinated toluene compound of at least 85%.