Issued Patents All Time
Showing 1–22 of 22 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5362908 | Catalyst and method for purifying crude terephthalic acid, isophthalic acid or naphthalene dicarboxylic acid | Ricky L. Wittman | 1994-11-08 |
| 5354898 | Method for purifying crude aromatic carboxylic acids | — | 1994-10-11 |
| 4937378 | Purification of crude isophthalic acid | — | 1990-06-26 |
| 4933491 | Method for purifying a crude naphthalene dicarboxylic acid | Rusins Albertins, Stephen J. Pietsch, Juergen K. Holzhauer | 1990-06-12 |
| 4933492 | Purification of crude isophthalic acid | Ricky L. Wittman | 1990-06-12 |
| 4892972 | Purification of crude terephthalic acid | David E. James | 1990-01-09 |
| 4833269 | Method for purifying terephthalic acid recycle streams | — | 1989-05-23 |
| 4808751 | Method for reactivating a group VIII noble metal catalyst for use in the purification of crude terephthalic acid | Ricky L. Wittman | 1989-02-28 |
| 4743577 | Catalyst composition | Ricky L. Wittman | 1988-05-10 |
| 4728630 | Rhodium on carbon catalyst | Ricky L. Wittman | 1988-03-01 |
| 4629715 | Purification of terephthalic acid to relatively low levels of 4-carboxybenzaldehyde and catalyst therefor | — | 1986-12-16 |
| 4260546 | Aged molten color of maleic anhydride | Donald E. Thomka | 1981-04-07 |
| 4234494 | Formation, purification and recovery of phthalic anhydride | David Aaron Palmer | 1980-11-18 |
| 4233227 | Phthalic anhydride formation and separation | David Aaron Palmer | 1980-11-11 |
| 4220596 | Separation of phthalic anhydride from vapor mixture also containing water vapor | Jeffrey H. Schott, David Aaron Palmer | 1980-09-02 |
| 4215053 | Production of ortho-phthalic acid and its conversion and recovery of phthalic anhydride | David Aaron Palmer, George E. Kuhlmann, Houssam M. Naim, Nicholas C. Huie | 1980-07-29 |
| 4215054 | Production of liquid ortho-phthalic acid and its conversion to high purity phthalic anhydride | George E. Kuhlmann, Sydney G. Horsfield, David Aaron Palmer | 1980-07-29 |
| 4215056 | Formation, purification and recovery of phthalic anhydride | David Aaron Palmer | 1980-07-29 |
| 4215055 | Production of liquid ortho-phthalic acid and its conversion to high _purity phthalic anhdyride | David Aaron Palmer, George E. Kuhlmann, Sydney G. Horsfield | 1980-07-29 |
| 4215051 | Formation, purification and recovery of phthalic anhydride | David Aaron Palmer | 1980-07-29 |
| 4215052 | Production of liquid ortho-phthalic acid and its conversion to high purity phthalic anhydride | David Aaron Palmer, George E. Kuhlmann, Houssam M. Naim, Nicholas C. Huie | 1980-07-29 |
| 4197247 | Removal of bromine from phthalic anhydride | Delbert H. Meyer | 1980-04-08 |