Kuraray process

Figure 22 The Kuraray process for the production of 1,9-nonanediol or 1-octanol...

On the industrial level, aqueous two-phase systems are used more often than nonaqueous two-phase systems. The Kuraray Co. operates a pilot plant for the hydrodimerization of 1,3-butadiene in a two-phase system with a Pd/tppms catalyst (140). The reaction is carried out in sulfolane-water, from which the products, the octadienols, separate. The final products can be octanol or nonanediol made by subsequent isomerization and hydroformylation. The capacity of the Kuraray process is about 5000 tons/year. 

In the Kuraray process for the production of nonane-1,9-diol two steps involve the use of aqueous biphasic catalysis Pd/tppms catalyzed telomerization of butadiene with water as a reactant and Rh/tppms catalyzed hydroformylation (Fig. 7.14) [51]. 

An interesting variant of entry 5 is entry 11, in which one of the educts is a polar and the other a nonpolar reactant yielding organic products. Once again the catalyst is in the aqueous phase and thus easily separated from the products. This technique is used in the telomerization of butadiene with water (Kuraray process cf. Section 6.7) and the telomerization of butadiene with ammonia (see Section 4.2.2). 

Two process variants have been described. A type n process [91] resembles the Union Carbide process for butenes hydroformylation (see 8.6.1). Rapid oxidation of the diphosphite ligands by air ingress in vacuum distillation columns is mitigated by addition of an excess of sacrificial ligand (tri-orthotolylphosphine). In a type IVA process, very much like the Kuraray process (see 8.6.4.1), apolar and polar solvents are applied to effect the desired combinahon of one-phase reachon fohowed by phase separation, with most Rh/diphosphite catalyst in the apolar layer [92,93]. 

In the late 1980s, new fully aromatic polyester fibers were iatroduced for use ia composites and stmctural materials (18,19). In general, these materials are thermotropic Hquid crystal polymers that are melt-processible to give fibers with tensile properties and temperature resistance considerably higher than conventional polyester textile fibers. Vectran (Hoechst-Celanese and Kuraray) is a thermotropic Hquid crystal aromatic copolyester fiber composed of -hydroxyben2oic acid [99-96-7] and 6-hydroxy-2-naphthoic acid. Other fully aromatic polyester fiber composites have been iatroduced under various tradenames (19). 

The People s RepubHc of China introduced Kuraray technology and started production of PVA fiber by a wet spinning process in 1965. Its annual capacity reached 165,000 tons in 1986 (9). The Democratic People s RepubHc of Korea produce PVA and reportedly have an annual production capacity of 50,000 tons (9). 

Boric acid/alkaU spinning has been commercialized in Kuraray Co. and Unitika Co. in Japan, and is reportedly under research and development also in the People s RepubHc of China as a process for producing high strength PVA fiber to be used for replacing asbestos (9). 

Much of the work with regard to this process was done by the French Petroleum Institute (113) and by the Kuraray Co. (108). In the CIS, a sinulat process which begins with cmde C s was developed (114). A one-step process that begins with isobutylene and methanol has been disclosed (108,115). This process is beheved to have significant economic advantages over the original route. 

Functional Olefin Hydroformylation. There has been widespread academic (18,19) and industrial (20) interest in functional olefin hydroformylation as a route to polyfiinctional molecules, eg, diols. There are two commercially practiced oxo processes employing functionalized olefin feedstocks. Akyl alcohol hydroformylation is carried out by Arco under Hcense from Kuraray (20,21). 1,4-Butanediol [110-63 ] is produced by successive hydroformylation of aHyl alcohol [107-18-6] aqueous extraction of the intermediate 2-hydroxytetrahydrofuran, and subsequent hydrogenation. 

Kuraray has commercialized a process for producing 3-meth5l-l,5-pentanediol [4457-71-0] from 3-methyl-3-butenol (20). 

KURASEP [Kuraray Separation] A process for separating nitrogen from air by a variant of the PSA process, using carbon molecular sieve as the adsorbent. Developed by Kuraray Chemical Company. 

Another process that utilizes biphasic aqueous catalysis is the hydrodimerization of butadiene and water, run at 5000 tpa by Kuraray in Japan [138]. This process has two... 

Since its discovery in the late 1960s, the telomerization process has matured and been commercialized. The Kuraray company first commercialized an application of the telomerization process in 1991 by producing the plasticizer 1-octanol on a scale of 5,000 ton/year via the dimerization of 1,3-butadiene with the addition of water to... 

Scheme 2 Two industrial processes involving a palladium-catalyzed telomerization step the production of 1-octanol by Kuraray (left) and 1-octene by Dow Chemical (right)...

The principal develo naents achieved in this area, some of which have cohnfnated in industrial production, are those of Bayer, Davy Powergas, IFP, Kuraray and the Soviet Union. Using a C4 cut containing isobutene, these processes manufacture isoprene by the addition of fommldehyde in a first step (Prins reaction), followed by cat ytk cracking of the dioxane formed in a second step ... 

To evaluate the basic characteristics of de-SOx over ACF, comparison was made between 4 kinds of commercialized ACFs under the untreated condition. Table 1 shows the comparison of the properties of ACFs. Because the structures such as an external surface area, specific surface area, and pore size are unified in the manufacturing process, there is slight difference in structure of raw materials. But the compositions of raw materials significantly vary with types phenol-type (Kuraray Chemicals co.,ltd.) or... 

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