# US 4,394,526 A · Para-cresol halide salt complex useful for separating para-cresol from meta-cresol

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- Number: US 4,394,526 A
- Document ID: US4394526A
- Status: Granted
- Kind: A
- Application number: 06/191,203
- Filed: 1980-09-26
- Granted: 1983-07-19
- Earliest claimed: 1979-06-29
- Assignees: Koppers Company, Inc.
- Inventors: Gerd Leston
- Web page: https://patentgrep.com/patent/US4394526A

## CPC

- C07C 37/86: by treatment giving rise to a chemical modification (chemisorption C07C37/82)
- C07C 39/235: Metal derivatives of a hydroxy group bound to a six-membered aromatic ring
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS

## Abstract

Para-cresol is separated from a mixture comprising meta-cresol and various other methylated and ethylated phenols by preferentially complexing the para-cresol with one or more anhydrous or dehydrated inorganic salts selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The anhydrous inorganic salt is added to the phenolic mixture in an amount to give a mole ratio of salt to para-cresol in the mixture in the range of about 0.5 mole to one to about 1.5 mole to one. The para-cresol and salt form a complex and the complex is removed from the mixture of methylated and ethylated phenols. Then the complex is decomposed to recover the para-cresol and salt; the recovered salt may be recycled to complex with more para-cresol.

## Claims

### Claim 1

A complex between para-cresol and an anhydrous or dehydrated inorganic halide salt selected from the group consisting of calcium bromide, magnesium chloride, lithium bromide and manganese bromide, said complex formed in the presence of meta-cresol and a non-aqueous solvent.

### Claim 2 (depends on 1)

The complex of claim 1 wherein said halide salt is calcium bromide.

### Claim 3 (depends on 1)

The complex of claim 1 wherein said non-aqueous solvent is toluene.

### Claim 4 (depends on 1)

The complex of claim 1 wherein said complex is formed in the presence of a complexing initiator.

### Claim 5 (depends on 4)

The complex of claim 4 wherein said complexing initiator is ethanol.