Method for the decomposition of cumene hydroperoxide
View Patent ↗A method of producing phenol, acetone and alpha-methyl styrene. A mixture of cumene hydroperoxide and dimethylbenzyl alcohol is provided. The mixture is subjected to a first stage reaction in the presence of about 0.5 to 1.5 wt. % water and about 20 to 400 ppm sulfuric acid at a reactor pressure of about 450 to 760 mm Hg, a temperature of about 60 to 85° C., and a residence time of 4 to 45 minutes to produce a composition having an acetone to phenol mole ratio of about 1 to 1.5. The composition is subjected to a second stage reaction in the presence of about 0.5 to 3 wt. % additional water with a second stage reactor temperature of about 110 to 150° C. and a residence time of 0.5 to 30 minutes.
1. A method of producing phenol, acetone and alpha-methyl styrene, the method comprising the steps of:
providing a mixture of cumene hydroperoxide and dimethylbenzyl alcohol;
subjecting the mixture to a first stage reaction in the presence of about 0.5 to 1.5 wt. % water and about 20 to 400 ppm sulfuric acid at a reactor pressure of about 450 to 760 mm Hg, a temperature of about 60 to 85° C., and a residence time of 4 to 45 minutes to produce a composition having an acetone to phenol mole ratio of about 1 to 1.5; and
subjecting the composition to a second stage reaction in the presence of about 0.5 to 3 wt. % additional water with a second stage reactor temperature of about 110 to 150° C. and a residence time of 0.5 to 30 minutes.
2. The method of claim 1 , wherein the mixture is subjected to the first stage reaction at about 450 to 500 mm Hg operating pressure, about 78 to 80° C. operating temperature, a 5 to 6 minute residence time and in the presence of about 300 to 350 ppm sulfuric acid.
3. The method of claim 2 , wherein the mixture has a water content of about 1.0 to 1.2 wt. % while subjecting the mixture to the first stage reaction to produce a composition having an acetone to phenol mole ratio of about 1 to 1.2.
4. The method of claim 1 , wherein the composition is subjected to the second stage reaction with a residence time of 0.7 to 1.0 minutes, a temperature of about 120 to 140° C. and with about 1 to 2 wt. % additional water.
5. The method of claim 1 , wherein exit concentrations of dicumyl peroxide after the second stage reaction are maintained at about 0.01 to 0.15 wt. %.
6. The method of claim 1 , wherein exit concentrations of dicumyl peroxide after the second stage reaction are maintained at about 0.02 to 0.03 wt. %.
7. The method of claim 1 , wherein exit concentrations of dicumyl peroxide after the second stage reaction are maintained at about 0.06 to 0.10 wt. %.
8. The method of claim 1 , wherein the mixture is subjected to the first stage reaction at atmospheric to slightly negative pressure, a residence time of 15 to 45 minutes and in the presence of about 20 to 50 ppm sulfuric acid to produce a composition having an acetone to phenol ratio of about 1.0.
9. The method of claim 1 , wherein the composition is subjected to the second stage reaction with a residence time of 5 to 20 minutes, a temperature of about 120 to 140° C. and about 1 to 2 wt. % additional water.
10. The method of claim 1 , wherein the temperature while subjecting the composition to the second stage reaction is about 134 to 138° C.