UOP Udex Process

UOP s Parex Process UOP Sulfolane process UOP Udex Process Upilex UpilexR... 

Sulfolane A process for removing aromatic hydrocarbons from petroleum fractions by liquid-liquid extraction using sulfolane (tetramethylene sulfone tetrahydrothiophene-1,1-dioxide) at approximately 190°C. Developed by Shell Development Company in 1959 and first commercialized in 1962 now licensed through UOP. It replaced the Udex process. Sulfolane is used for another purpose in the Sulfinol process. 

The first economic version of aromatics extraction, available industrially, was the Udex process, developed by Daw and licensed by UOP since 195Z Due to competition from new techniques, it has been practically abandoned since 1965, or its facilities altered and their production capacities increased. 

Removal of Aromatic Compounds. Because of the demand for high-purity aromatic compounds for petrochemical feedstocks, several processes have been developed for BTX (benzene, toluene, and xylenes) recovery from distillate streams. In these processes, aromatic compounds are separated from nonaromatic compounds by liquid—liquid extraction using polar solvents. The three major processes in use are the UOP—Dow UDEX process (di- or triethylene glycol solvent), the UOP sulfolane process (tetrahydrothiophene 1,1-dioxide), and the Union Carbide TETRA process (tetraethylene glycol). 

Sulfolane has a markedly better capacity than diethylene glycol for dissolving aromatics. In the Sulfolane process, first carried out technically by Shell and UOP in 1961, the mass ratio of solvent to feedstock is 3-6 1. A large number of plants which used to apply the Udex process have now been revamped to sulfolane use (Figure 4.7). 

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