Introduction to Aniline Catalyst

I. Basic Concepts

Aniline catalyst, also known as modified copper catalyst, is mainly used in the reaction of nitrobenzene hydrogenation to produce aniline. It is an improved catalyst in which copper is loaded on a silica carrier and a second component such as Cr and Mo is added.

II. Development History

The industrial production of aniline began in 1857, initially using the nitrobenzene iron powder reduction method. However, this method has the disadvantages of large equipment, severe corrosion, large iron powder consumption, and serious "three wastes" pollution.

After the 1950s, the advanced nitrobenzene catalytic hydrogenation method gradually replaced the nitrobenzene iron powder reduction method and became the main method for preparing aniline. Among them, the catalytic system for nitrobenzene catalytic hydrogenation to produce aniline mainly includes the Cu/SiO2 system in which copper is loaded on a silica carrier.

III. Main Types and Characteristics

Cu/SiO2 catalyst: It has the advantages of cheap and easy-to-obtain raw materials, simple and feasible preparation method, low cost, and good selectivity. But the disadvantage is that it has poor anti-toxicity and trace organic sulfides can easily poison the catalyst.

Cu-Cr/SiO2 catalyst: Chromium is added as a co-catalyst on the basis of Cu/SiO2 catalyst, which improves the performance of the catalyst, but the stability is still poor.

Cu-Cr-Mo/SiO2 catalyst: Molybdenum is further added, and the performance is greatly improved compared with the modified copper catalyst used in industry. The modification greatly increases the catalyst loading, which can improve the production capacity of equipment in industry and reduce production costs.

IV. Applications

Nitrobenzene hydrogenation to aniline: The core application of aniline catalyst, nitrobenzene is reduced to aniline through hydrogenation reaction.

Ortho-nitrotoluene hydrogenation to ortho-toluidine: Another important application of aniline catalyst, which can be used to prepare organic compounds such as ortho-toluidine.

V. Storage and transportation

Storage conditions: Aniline catalyst should avoid contact with other chemicals during storage, keep ventilation and dry, and avoid direct sunlight.

Transportation requirements: Although aniline catalyst itself is non-toxic, odorless, non-flammable and non-explosive, it is still necessary to pay attention to safety issues such as moisture-proof and damage-proof during transportation.

In summary, aniline catalyst is an important chemical catalyst with wide application value in the hydrogenation reaction of nitrobenzene and its derivatives. With the continuous development of the chemical industry, the performance and preparation process of aniline catalyst will also be continuously optimized and improved.