UOP Sarex process

UOP raffinate process UOP Sarex process UOP Sorbex process UOP Sorbex processes UOP Sorbex separation... 

Polymeric cation-exchange resins are also used in the separation of fmctose from glucose. The UOP Sarex process has employed both 2eohtic and polymeric resin adsorbents for the production of high fmctose com symp (HFCS). The operating characteristics of these two adsorbents are substantially different and have been compared in terms of fundamental characteristics such as capacity, selectivity, and adsorption kinetics (51). 

The UOP Sarex process has been used since 1978 for the separation of high purity fmctose from a mixture of fmctose, glucose, and polysaccharides (87,88). The pilot-plant performance of fmctose—glucose separation is given in Table 6. 

Displacement-purge forms the basis for most simulated continuous countercurrent systems (see hereafter) such as the UOP Sorbex processes. UOP has licensed close to one hundred Sorbex units for its family of processes Parex to separate p-xylene from C3 aromatics, Molex tor /i-paraffin from branched and cyclic hydrocarbons, Olex for olefins from paraffin, Sarex for fruc tose from dextrose plus polysaccharides, Cymex forp- or m-cymene from cymene isomers, and Cresex for p- or m-cresol from cresol isomers. Toray Industries Aromax process is another for the production of p-xylene [Otani, Chem. Eng., 80(9), 106-107, (1973)]. Illinois Water Treatment [Making Wave.s in Liquid Processing, Illinois Water Treatment Company, IWT Adsep System, Rockford, IL, 6(1), (1984)] and Mitsubishi [Ishikawa, Tanabe, and Usui, U.S. Patent 4,182,633 (1980)] have also commercialized displacement-purge processes for the separation of fructose from dextrose. 

The SMB technology was developed by UOP and its major field of application is in the area of binary separations. For example, SMB has been used in the chemical industry for several separations known as SORBEX processes [1-3], which include, among others, the PAREX process for p-xylene separation from a Cs aromatic fraction [4], the OLEX process for the separation of olefins from paraffins, the SAREX process to separate fructose from glucose [4] and the MOLEX process [5]. Simulated moving bed is being used particularly for separation of enantiomers from racemic mixtures or from the products of enantioselective synthesis [6,7]. It has been used for the production of fine chemicals, and petrochemical intermediates, such as Cg-hydrocarbons [8], food chemistry such as fatty acids [2], or certain sugars from carbohydrate mixtures [8] and protein desalination [9]. 

Sarex (1) [Saccharide extraction] A version of the Sorbex process, for separating fructose from mixtures of fructose and glucose. The usual feed is com syrup. The adsorbent is either a proprietary zeolite or an ion-exchange resin. Unlike all the other Sorbex processes, the solvent is water. The process depends on the tendency of calcium and magnesium ions to complex with fructose. The patents describe several methods for minimizing the dissolution of silica from the zeolite. The process is intended for use with a glucose isomerization unit, so that the sole product from com syrup is fructose. Invented by UOP in 1976 by 2003, five plants had been licensed. 

Simulated moving-bed (SMB) processes have been widely nsed for difficult, liquid-phase separations (Ruthven, 1984 Humphrey and Keller, 1997 Juza et al 2000). Sorbex is the generic name used by UOP for these processes. The most important application is the separation of the xylene isomers, named the Parex process. Other commercialized SMB separations include n-paraffins/isoparaffins (Molex), olefins/paraffins (Olex), fructose/glucose (Sarex), and chiral SMB separations (Juza et al., 2000). A host of other separations have been demonstrated (Humphrey and Keller, 1997), although the commercial status of these applications is unknown. These demonsffated separations include separation of hydroxyparaf-finic dicarboxylic acids from olefinic dicarboxylic acids removal of thiophene, pyridine, and phenol from naphtha separation of unsaturated fatty acid methyl esters from saturated fatty acid methyl esters and separation of saturated fatty acids from unsaturated fatty acid (Humphrey and Keller, 1997). 

This process was developed and commercialized by UOP and called the Sorbex process, a general name applied to the separation of p-xylence from C8 reformates (Parex) (Broughton ei al., 1970 deRosset et al, 1978, Broughton, 1984), normal paraffins from isoparaffins and aromatic hydrocarbons (Molex), linear olefins from paraffins (Olex) and fructose from dextrose and polysaccharides (Sarex) and so on. 

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