Claims
- 1. A process for activating catalysts for production of .epsilon.-caprolactam, which comprises contacting a zeolite selected from the group consisting of pentasil crystalline silica or pentasil crystalline aluminosilicate having an Si/Al atom ratio of least 5 with either
- (1) an aqueous solution of ammonium salts and at least one basic material selected from ammonia, lower alkylamines, allylamines and alkylammonium hydroxides, or
- (2) ammonia water.
- 2. A process according to claim 1, wherein the lower alkylamine have the formula:
- NR.sub.1 R.sub.2 R.sub.3 ( 1)
- wherein R.sub.1, R.sub.2 and R.sub.3 each is a hydrogen atom or a lower alkyl group but R.sub.1, R.sub.2 and R.sub.3 all are not hydrogen atoms.
- 3. A process according to claim 1, wherein the lower alkylamines have C.sub.1-12 in the total.
- 4. A process according to claim 1, wherein the allylamines have C.sub.3-9 in the total.
- 5. A process according to claim 1, wherein the alkylammonium hydroxides have the formula:
- R.sub.4 R.sub.5 R.sub.6 R.sub.7 N.sup.+ ON.sup.- ( 2)
- wherein R.sub.4, R.sub.5, R.sub.6 and R.sub.7 each is a hydrogen atom, a lower alkyl group, an aralkyl group, an aryl group or an allyl group but R.sub.4, R.sub.5, R.sub.6 and R.sub.7 all are not hydrogen atoms.
- 6. A process according to claim 5, wherein the alkylammonium hydroxides have C.sub.1-20 in the total.
- 7. A process according to claim 1, wherein the catalysts are crystalline silica or crystalline metallosilicates.
- 8. A process according to claim 1, wherein the contact with the aqueous solution or ammonia water is effected after activity of the catalyst is degraded.
- 9. A process according to claim 8, wherein the degraded catalyst is brought into contact with ammonia gas.
- 10. A process according to claim 1, wherein the degraded catalyst has been burned in the presence of molecular oxygen-containing gas with or without alcohols.
- 11. A process according to claim 1, wherein said .epsilon.-caprolactam is produced via Beckmann rearrangement reaction.
- 12. A process according to claim 11, wherein the contact with the aqueous solution or ammonia water is effected before the reaction of Beckmann rearrangement.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2-406823 |
Dec 1990 |
JPX |
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Parent Case Info
This is a division of application Ser. No. 07/811,627, now U.S. Pat. No. 5,212,302, filed Dec. 23, 1991.
US Referenced Citations (12)
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Divisions (1)
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Number |
Date |
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Parent |
811627 |
Dec 1991 |
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