Nitric Acid → 2,3-Dinitrotoluene

HRID 1979873Notes

Reaction equation

HRID 1979873 reaction equation
[N+:1]([C:4]1[CH:9]=[CH:8][C:7](C)=[CH:6][CH:5]=1)([O-:3])=[O:2].[N+:11]([O-:14])(O)=[O:12].S(=O)(=O)(O)O.[C:20]1(C)C=CC=CC=1>>[N+:11]([C:9]1[C:4]([N+:1]([O-:3])=[O:2])=[C:5]([CH3:20])[CH:6]=[CH:7][CH:8]=1)([O-:14])=[O:12]

Participants

5

Reactant 4

HCID 944Nitric AcidHCID 1118Sulfuric AcidHCID 1140TolueneHCID 74734-Nitrotoluene

Product 1

HCID 117612,3-Dinitrotoluene

Procedure

This invention relates to an improvement in a process for purifying dinitrotoluene is prepared by first reacting toluene or mononitrotoluene with nitric acid in the presence of sulfuric acid, separating the crude dinitrotoluene from the resulting aqueous phases and then contacting the resultant crude dinitrotoluene with an alkaline material to form a purified dinitrotoluene product and an aqueous by-product phase. The improvement in the process relates to selectively maintaining a significant proportion of 2,4-dinitroorthocresol in the dinitrotoluene product and away from the effluent waste while permitting other nitrophenolic impurities to pass to the aqueous by-product phase or effluent waste. The improvement comprises: monitoring the pH of the aqueous phase formed during said contacting step with a pH sensitive instrument and then terminating said contacting step when the pH of the resultant aqueous phase is within a pH range of about 5.8 to 6.4.

Workup

  1. customfor purifying dinitrotoluene
  2. customis prepared
  3. customseparating the crude dinitrotoluene from the resulting aqueous phases

Sources & evidence

ORD record
ord-ac723694805e46209e8cbd15c4db4b8c
Source dataset
uspto-grants-1984_11
Patent number
US04482769

Reaction notes

Loading…