2-chloro-4-nitroaniline (2-chloro-4-nitroaniline) is also known as o-chloro- p -nitroaniline, 4-amino-3-chloronitrobenzene (4-amino-3-chloronitrobenzene), the molecular formula is C 6 H 5 CIN 2 O 2 , the molecular weight is 172.
58, and the structural formula is
After p-nitroaniline is salted with hydrochloric acid, it is chlorinated with sodium hypochlorite to obtain the product
Technical formula (kg/t)
Reaction pot, filter press, storage tank, dryer
Add 450L of water, 1120kg of 30% hydrochloric acid to the reaction pot, increase the temperature to 50°C, add 185.
6kg of p-nitroaniline, and stir for 20min to dissolve
Add ice to cool down to about -2°C, slowly add 1120kg of 10% sodium hypochlorite solution from below the liquid surface, use starch potassium iodide test paper to test at any time during the reaction, it should be slightly blue
After about 4h, the feeding is finished, keep 0～2℃ and continue to stir and react for 2h.
Check with potassium iodide starch test paper and still show light blue unchanged, which is the end point
Add water to adjust the volume to 6000L, let it settle for precipitation, and remove the upper layer of waste acid
Add water to a total volume of 6000L
After stirring, let it stand, remove the waste acid layer, press filter, rinse with clean water, and dry, and the finished product is about 200kg
Assay: Accurately weigh about 2.
5g sample, place it in a 400mL clean drying cup, add 30mL hydrochloric acid and 100mL distilled water, heat and dissolve on an electric stove, add distilled water to dilute to a total of 300mL
This solution is cooled to 0 ~ 10 ℃
Then insert the tip of the burette into the solution, and under constant stirring, add 0.
5mol/L sodium nitrite standard solution (95% of the required amount) at once
Then take the tip of the burette out of the liquid surface, rinse the tip of the burette with distilled water, add 0.
5mo/L sodium nitrite standard solution drop by drop until the solution makes the potassium iodide-starch test paper slightly blue, and keep it for 5 minutes without fading, that is the end point
Do a blank experiment at the same time
In the formula: c——molar concentration of sodium nitrite standard solution, mol/L;
V——The volume of sodium nitrite standard solution consumed by the sample, mL;
V 1 ——The volume of sodium nitrite standard solution consumed in the blank experiment, mL;
G——The mass of the sample, g
Used as dyes, pigments and pharmaceutical intermediates, such as the synthesis of Disperse Red B, Silver Bead R, and Schistosomiasis-67 paste
(1) The raw material is highly toxic to nitroaniline, and the maximum allowable concentration in the air is 0.
The product is an organic drug
The chlorination equipment should be sealed, the operators should wear labor protection equipment, and the workshop should be well ventilated
(2) The products are packed in iron drums or plastic bags and stored in a cool, dry place
Store and transport in accordance with toxic chemicals regulations