Aromax

Aromatic 100 solvent Aromatic 150 solvent Aroma transport Aromax process Aromizing Process AromoxC/12 AromoxDMld AromoxDMCD Aromox DMHTD AromoxT/12 Aron alpha Arosolvan process Arosurf Aroxtex 5C... 

Currendy, there are three commercially available PX adsorption processes UOP s Parex, IFP s Eluxyl, and Toray s Aromax (not to be confused with Chevron s Aromax process for reforming naphtha into aromatics). In all of these processes, the feed and desorbent inlets and the product oudet ports are moved around the bed, simulating a moving bed. 

The Aromax process was developed in the early 1970s by Toray Industries, Inc. in Japan (95—98). The adsorption column consists of a horizontal series of independent chambers containing fixed beds of adsorbent. Instead of a rotary valve, a sequence of specially designed on—off valves under computer control is used to move inlet and withdrawal ports around the bed. Adsorption is carried out in the Hquid phase at 140°C, 785—980 kPA, and 5—13 L/h. PX yields per pass is reported to exceed 90% with a typical purity of 99.5%. The first Aromax unit was installed at Toray s Kawasaki plant in March 1973. In 1994, IFP introduced the Eluxyl adsorption process (59,99). The proprietary adsorbent used is designated SPX 3000. Individual on-off valves controlled by a microprocessor are used. Raman spectroscopy to used to measure concentration profiles in the column. A 10,000 t/yr demonstration plant was started and successfully operated at Chevron s Pascagoula plant from 1995—96. IFP has Hcensed two hybrid units. 

Such a concept was originally used in a process developed and Hcensed by UOP under the name UOP Sorbex (59,60). Other versions of the SMB system are also used commercially (61). Toray Industries built the Aromax process for the production of -xylene (20,62,63). Illinois Water Treatment and Mitsubishi have commercialized SMB processes for the separation of fmctose from dextrose (64—66). The foUowing discussion is based on the UOP Sorbex process. 

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. 

Aromax (1) A catalytic process for converting light paraffins to benzene and toluene, using a zeolite catalyst. Developed by Chevron Research Technology Company. Installations were planned for Mississippi, Thailand, and Saudi Arabia. 

Aromax (2) Also known as Toray Aromax. A chromatographic process for separating p-xylene from its isomers. Similar to the Parex (1) process, it operates in the liquid phase at 200°C, 15 bar. Developed in 1971 by Toray Industries, Japan. 

Aromax process, 1 665 25 171, 176 Aromizing-Aroformer process, 25 175 Arosolvan process, 3 606 P-Aroylacrylic acids, 15 486 2-Aroylbenzofurans, microwave-assisted synthesis of, 16 578 Array detector, 23 143 Array methodologies, 12 513-517 Arrays, large, 16 390 Array spotting/synthesis, in microarray fabrication, 16 385-387 Arrhenius equation, 10 85 14 622 ... 

The Parex, Toray Aromax and Axens Eluxyl processes are the three adsorptive liquid technologies for the separation and purification of p-xylene practiced on a large scale today. The MX Sorbex process is the only liquid adsorptive process for the separation and purification of m-xylene practiced on an industrial scale. We now consider a few other liquid adsorptive applications using Sorbex technology for aromatics separation that have commercial promise but have not found wide application. 

Pt-KBaL catalyst than over conventional reforming catalysts. However, the advantage diminishes as carbon number increases, so these technologies are primarily of interest for benzene production. It is therefore more efficient to complement conventional reforming with the zeolitic reforming process when a broader range of aromatic products is desired. Relatively large crystal size has been claimed to be beneficial for example in CP Chem s AROMAX process. Residual acidity on the catalyst has been shown to be detrimental [86]. 

Aromax process -for xylenes [XYLENES AND ETHYLBENZENE] (Supplement)... 

In the Aromax process, the adsorbent can be easily loaded, unloaded or regenerated at the level of each stage. Its total life is about 10 years. The operation takes place at a temperature below 200 0 at less than 2.10 Pa absolute. The number of stages can be increased by placing two or more horizontal adsorbers in series, depending on tbe type and volume of tbe feed to be treated and the performance required. 

Fig. 4.18. S iaration of /hxykae by adsorption. Toray Aromax process.

Otani.C., ICanaoka, M., Matsumura, IC. Akita. Sonoda, Aromax isolene. New psnxytene recovery and xylene isomenzacton. Processes developed by Toray , Clum. Scm. and Engng Rev. 3 tS. 38) 56-59 (1971 ... 

Aromax 18/12, 0 3837 (C2H OH)2lIO Deriphat 151C, N-Coco 6-amlnopropionic acid Armeen HT, RNH2 60% Cig 3 16 Armeen 12D, RNH2, 97% 0 2... 

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