反应详情

温度

80 °C

Next, when 100 cc of an aqueous solution containing 20.3 g (0.143 mole) of sodium hydrogenphosphate (Na2HPO4) was added, a white precipitate was formed. After stirring this at 80° C. for one hour, the white precipitate was thoroughly water-washed by the decantation method followed by separation by filtration and water-washing. The resulting white precipitate was dried at 120° C., calcined at 400° C. for 6 hours in a stream of air, and thereafter molded into granules of 10-16-mesh size. The LaPO4 catalyst (5 cc) thus obtained was packed in a Pyrex reaction tube of 12-mm inside diameter, which then was secured in an electric furnace held at 275° C. Next, while passing nitrogen from the top of the reaction tube through the catalyst layer at a gas space velocity of 480 liter/liter/hr, 14% ammonia water was passed through the catalyst layer at a liquid hourly space velocity of 0.5 liter/liter/hr for 30 minutes. The feed of the ammonia water was then stopped, and a feed liquid consisting of α-hydroxyisobutyramide, methanol and water in a mole ratio of 1:14:11.5 was fed at a liquid hourly space velocity of 0.26 liter/liter/hr. The gas leaving the catalyst layer was trapped in a dry ice trap coupled to the bottom of the reaction tube. When the products were quantitatively analyzed by gas chromatography, the molar yields of methyl methacrylate and methacrylic acid were 83.2% and 3.0%, respectively, based on the starting α-hydroxyisobutyramide.

1. additionwas added
2. customa white precipitate was formed
3. washwashed by the decantation method
4. customfollowed by separation by filtration and water-
5. washwashing
6. customThe resulting white precipitate was dried at 120° C.
7. waitcalcined at 400° C. for 6 hours in a stream of air
8. customThe LaPO4 catalyst (5 cc) thus obtained
9. customwas packed in a Pyrex reaction tube of 12-mm inside diameter, which
10. customheld at 275° C
11. waitwas passed through the catalyst layer at a liquid hourly space velocity of 0.5 liter/liter/hr for 30 minutes
12. customThe gas leaving the catalyst layer
13. customwas trapped in a dry ice trap