methylbenzene , Toluene (2)
The most important applications of aromatic compounds such as benzene, toluene and xylene, which show the importance of these compounds in the chemical industry, are shown in Figure (1).
Figure (1): The main applications of aromatic compounds in the world
One of the most important uses of toluene is to produce toluene diisocyanate. This process includes the following steps:
Niration Process:
At this stage of the reaction, toluene reacts with nitric acid and sulfuric acid to produce dinitro toluene and water.
Hydrogenation Process
At this stage of the process, dinitro-toluene reacts with hydrogen in the presence of a catalyst to form a mixture of toluenediamine TDA isomers and water.
Phosgenation Process
At this stage of the process, the TDA reacts with phosgene to produce a mixture of TDI isomers and hydrogen chloride as shown below.