The manufacturing method of p-nitrophenol is an important organic chemical raw material, widely used in fields such as medicine, pesticides, dyes, etc. Therefore, studying the manufacturing methods of nitrophenol has important practical significance. This article will introduce the method of preparing p-nitrophenol through hydrolysis reaction using p-nitrochlorobenzene as raw material
2、 Experimental principle: p-nitrochlorobenzene undergoes hydrolysis reaction in aqueous solution to generate p-nitrophenol and hydrogen chloride. This reaction belongs to a substitution reaction, and the reaction equation is as follows:
C6H4 (NO2) Cl+H2O → C6H4 (NO2) OH+HCl
III. Experimental Materials and Equipment
1 Experimental materials: p-nitrochlorobenzene, sodium hydroxide, water
2 Experimental equipment: four necked flask, reflux condenser tube, thermometer, stirrer, drip funnel, separation funnel, pH test paper
4. Experimental steps
1 Add a certain amount of p-nitrochlorobenzene and water to a four necked flask and stir evenly
2. Add a calculated amount of sodium hydroxide solution to the drip funnel, slowly drip it into a four necked flask, and control the reaction temperature within a certain range
3. After dripping, continue stirring for a certain period of time to allow the reaction to proceed fully
4. Use pH test paper to detect the pH value of the reaction solution. When the pH value reaches a certain value, stop stirring and let it stand for layering
5. Separate the lower liquid layer and wash it with water until neutral to obtain the crude product p-nitrophenol
6. Recrystallize and purify the crude product to obtain pure p-nitrophenol
5、 Experimental Results and Discussion
1 Experimental results: Through hydrolysis reaction, p-nitrophenol was successfully prepared with high yield
2. Experimental discussion:
(1) The control of reaction temperature has a significant impact on reaction rate and product purity, and an appropriate temperature range needs to be selected according to the actual situation
(2) The dosage and droplet acceleration of sodium hydroxide can also affect the progress of the reaction and the purity of the product, and experimental optimization is needed
(3) Recrystallization purification is an important guarantee for the purity of nitrophenol, and suitable solvents and crystallization conditions need to be selected
6、 Experimental summary: Through the hydrolysis reaction of nitrochlorobenzene, p-nitrophenol was successfully prepared, and the experimental results showed that this method is feasible. In the actual production process, it is necessary to optimize the experimental conditions according to the specific situation to improve the purity and yield of the product. At the same time, it is necessary to pay attention to safety issues during the experimental process to ensure the smooth progress of the experiment.
