Toluene is one of the "aromatic" compounds along with benzene and xylenes. There is limited chemical consumption of toluene but it may be converted to benzene by hydrodealkylation (THDA) or to benzene and xylenes by disproportionation (TDP) or transalkylation. Chemical applications include solvents and toluene diisocyanate (TDI).
Toluene diisocyanate (TDI)
Toluene diisocyanate (TDI) is an aromatic derivative produced by the nitration of toluene followed by phosgenation. TDI-based polyurethanes are used in flexible foams, coating resins, adhesives, sealants and elastomers.
Toluene Disproportionation (TDP)
Incremental mixed xylenes can be produced from available toluene through disproportionation. Technologies are available that will permit co-processing C9 aromatics with toluene into mixed xylenes. The analysis presented here gives the costs for a typical TDP unit processing toluene only, valuing the feedstock at its gasoline blending value. Xylenes production from gasoline value toluene, in general, has a lower cash cost of production than xylenes from reformate. This result is sensitive to co-product credits from benzene and other gasoline based co-products, and the position can be reversed if toluene is valued throughout at its market price.