Sulfuric Acid → P-Cresol

HRID 1016720Notes

Reaction equation

HRID 1016720 reaction equation
S(=O)(=O)(O)O.S([O-])([O-])=[O:7].[Na+].[Na+].[OH-:12].[Na+].S(=O)=[O:15].[C:17]1([CH3:23])[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1>>[C:17]1([CH3:23])[C:22]([OH:12])=[CH:21][CH:20]=[CH:19][CH:18]=1.[CH:18]1[C:19]([OH:15])=[CH:20][CH:21]=[CH:22][C:17]=1[CH3:23].[CH:19]1[C:20]([OH:7])=[CH:21][CH:22]=[C:17]([CH3:23])[CH:18]=1

Participants

8

Reactant 5

HCID 1118Sulfuric Acid2×HCID 1119Sulfur DioxideHCID 1140TolueneHCID 14798Sodium Hydroxide2×HCID 24437Sodium Sulfite

Product 3

HCID 335O-CresolYield 6%HCID 342M-CresolYield 6%HCID 2879P-CresolYield 80%

Procedure

Cresol is produced from alkaline melts of toluenesulfonates in four reaction steps. Toluene is first sulfonated by concentrated sulfuric acid, and the resultant sulfonic acid mixture is neutralized with sodium sulfite or sodium hydroxide solution and then fused with sodium hydroxide at approximately 300° C. An aqueous solution of the melt is then acidified with sulfur dioxide or sulfuric acid, which releases the cresols. Generally, a cresol mixture is produced comprising 6 to 12% o-cresol, 6 to 12% m-cresol and 80 to 85% p-cresol. The p-cresol can be separated off by means of fractional crystallization. However, this process has the disadvantage that large amounts of sodium sulfite are produced that must be disposed of.

Sources & evidence

ORD record
ord-2125eea0188c4053942fbf67f510003e
Source dataset
uspto-grants-2002_11
Patent number
US06476277B2

Reaction notes

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