O-phenylenediamine (OPD) is an important organic chemical raw material, which is widely used in dyestuffs, pharmaceuticals, pesticides, rubber and other fields. This article will introduce the manufacturing method of o-phenylenediamine, including raw materials, process flow, operation steps, equipment selection and other aspects.
I. Raw materials
The raw material for the manufacture of o-phenylenediamine is mainly aniline. Aniline is a common organic compound, which can be obtained from coal tar or petroleum cracking.
II. Process flow
The manufacturing process of o-phenylenediamine mainly includes the following steps:
1. Oxidation of aniline: aniline is mixed with oxidizing agent to carry out oxidation reaction to produce o-phenylenediamine and water. Commonly used oxidizing agents are nitric acid and hydrogen peroxide.
2. Neutralization: Neutralize the acid generated by the oxidation reaction and adjust the pH to precipitate o-phenylenediamine.
3. Filtration: Separate the precipitated o-phenylenediamine by filtration to obtain the crude product.
4. Refining: Refine the crude product, remove impurities and get pure o-phenylenediamine product.
3. Operation steps
1. Dosing: Dosing aniline and oxidizer according to certain proportion, add into the reactor.
2. Oxidation reaction: Heat and stir in the reactor to make the aniline and oxidant fully react to produce o-phenylenediamine and water.
3. Neutralization and adjustment: Neutralize the acid in the reactor and adjust the pH value, so that the o-phenylenediamine is precipitated.
4. Filtration and separation: The precipitated o-phenylenediamine is filtered and separated to obtain the crude product.
5. Refining treatment: Refine the crude product, remove impurities and get pure o-phenylenediamine product.
Four, equipment selection
The equipment to be used in the manufacturing process of o-phenylenediamine includes reactor, stirrer, filter, refining equipment and so on. When selecting the equipment, it is necessary to make comprehensive consideration according to the production scale, product quality, safety and environmental protection and other factors, and select the equipment that meets the production requirements.
V. Safety and environmental protection requirements
In the manufacturing process of o-phenylenediamine, it is necessary to pay attention to the safety and environmental protection requirements, and take corresponding measures to ensure the safety and environmental protection of the production process. For example, strengthen the maintenance of equipment to prevent leakage accidents; control the discharge of wastewater, waste gas and other pollutants to meet environmental standards.
VI.Manufacturing Advantages and Deficiencies
The manufacturing method of o-phenylenediamine has the advantages of easy-to-obtain raw materials, simple process and convenient operation, so it has been widely used in the field of chemical production. However, there are some shortcomings in the method, such as the production process will produce a large amount of wastewater, exhaust gas and other pollutants, which requires effective treatment measures; at the same time, due to the toxicity and corrosiveness of o-phenylenediamine, the safety requirements for the production equipment and operators are high.
In summary, the manufacturing method of o-phenylenediamine needs to comprehensively consider factors such as raw materials, process flow, operation steps, equipment selection, safety and environmental protection requirements, etc., in order to ensure the safety and environmental friendliness of the production process, and improve product quality and production efficiency.
