To selectively convert toluene to mixed xylene and high-purity benzene using ExxonMobil Chemical’s Toluene DisProportionation 3rd Generation (MTDP-3) process.
Dry toluene feed and up to 25 wt% C9 aromatics along with hydrogen-rich recycle gas are pumped through feed effluent heat exchangers and the charge heater into the MTDP-3 reactor (1). Toluene disproportionation occurs in the vapor phase to produce the mixed xylene and benzene product. Hydrogen-rich gas from the high-pressure separator (2) is recycled back to the reactor together with makeup hydrogen. Unconverted toluene is recycled to extinction.
Reactor yields, wt%:
Feed Product
C5 and lighter 1.3
Benzene 19.8
Toluene 100.0 52.0
Ethylbenzene 0.6
p-Xylene 6.3
m-Xylene 12.8
o-Xylene 5.4
C9+ aromatics _____ 1.8
100.0 100.0
Toluene conversion, wt% 48
Operating conditions: MTDP-3 operates at high space velocity and low H2 / hydrocarbon mole ratio. These conditions could potentially result in increased throughput without reactor and/or compressor replacement in retrofit applications. The third-generation catalyst offers long operating cycles and is regenerable.
Licensor: ExxonMobil Chemical Technology Licensing LLC (retrofit applications)
