Brief introduction
N-methylaniline is an important intermediate for organic synthesis and dyes and is widely used for the production of disperse dyes, cationic dyes and other dyes through synthesis. It is also an important raw material for pesticides, pharmaceutical products, rubber assistants, and stabilizers of explosives and can be used as an additive and a solvent of lead-free, high-grade, or all-purpose gasoline.
Process
After the methanol and aniline are mixed they enter a vaporizer, then, after vaporization, enter a fixed-bed reactor filled with catalyst where they react at normal pressure and a temperature of 200~280℃. After condensation, separation, and vacuum rectification of the resulting products, the result is N-methylaniline. The methanol and aniline that do not react fully are recycled.
Technical indicators
|
Item |
Specification |
Unit |
Consumption quota |
|
Methanol |
Industrial grade 1 |
t |
0.55 |
|
Aniline |
≥99.3% |
t |
0.94 |
|
N-alkylation catalyst |
Special purpose |
t |
0.002 |
|
Electricity |
220V/380V |
kWh |
900 |
|
Cooling water |
0.35MPa |
m3 |
100～300 |
|
Steam |
0.60MPa |
t |
7.0 |
Product indicators
|
Purity |
Aniline content |
Methylaniline content |
Moisture content |
|
≥99.0% |
≤0.2% |
≤0.7% |
≤0.1% |
Special-purpose catalyst
The CNW-1 catalyst was first used in industrial units in 1983 and, now, after more than 20 years of industrial applications we can see that it is highly active and has high thermal stability, long life, and high selectivity, and it is now a national leader. The CNW-1 aniline N-alkylation catalyst project took second prize in the S&T progress awards in Sichuan province and the CNW-1 aniline N-alkylation catalyst won an excellent new product award.
Waste treatment
This generates only a small amount of waste gas and no serious pollution. The wastewater mainly contains trace amounts of methanol and amines and can be treated in a centralized way and discharged after it meets standards.