Eastman Chemical Company cellulose acetate

Eastman Chemical Company, together with Halcon, developed a commercial acetic anhydride process to an industrial scale [41b, 47]. This process starts with coal to make a hydrogen-rich synthesis gas, which is purified (Figure 4). A portion of the syn gas is separated to produce methanol from 2 1 H2/CO. Part of the methanol is used to scrub H2S from the coal-gasification step. The remainder of the methanol is combined with acetic acid to make methyl acetate. The methyl acetate is carbonylated to give acetic anhydride. The acetic anhydride is used to produce cellulose acetate in another process, and the resulting acetic acid is recycled to the esterification section. The acetic anhydride step of the pro-... 

Materials. VEC was prepared by the catalyzed addition of CO2 to 3,4-epoxy-l-butene using conditions typical of that used industrially [77], then purified by vacuum distillation. Other raw materials were used as received without any additional purification. Mixed xylenes, vinyl acetate (VA), butyl acrylate (BA), butyl methacrylate (BMA), methyl methacrylate (MMA), styrene (St), and t-butyl hydroperoxide were obtained from Aldrich Chemical Company. Lupersol 575 (t-amyl peroxy (2-ethylhexanoate)) was supplied by Elf Atochem. Vazo 67 (2,2 -azobis(2-methylbutyronitrile)) was obtained from DuPont Chemical Company. Vinyl pivalate (NE05), vinyl 2-ethylhexanoate (V2EH), Tergitol NP-40 (non-ionic surfactant) and QP-300 (hydroxy ethyl cellulose) were obtained from Union Carbide Coq)oration. Aerosol OT-75 (surfactant) was obtained from Cytec. Sodium formaldehyde sulfoxylate was obtained from Henkel Corporation. Ethyl 3-ethoxy propionate (EEP), propylene glycol monomethyl ether (PM) and PM acetate (PM Ac) are Eastman Chemical Company products. 

If one looks at the overall process as it is integrated to cellulose acetate manufacture (equations [21] through [26]) the attraction of this process becomes apparent. By instituting a methyl acetate carbonylation, Eastman Chemical Company was able to replace the very energy intensive ketene process with a nearly thermodynamically neutral esterification as a method to remove water and subsequent exothermic carbonylation in the manufacture of cellulose acetate. 

Five different kinds of fibers were used for the study. Cotton fiber is the base fiber, and four types of binder fibers, ordinary cellulose acetate (OCA), plasticized cellulose acetate (PCA), Eastar Bio copolyester unicomponent (Eastar), and Eastar Bio copolyester bicomponent (Eastar/PP) fibers. The chemical name of Eastar Bio copolyester is poly(tetramethylene adipate-co-terephthalate) (PTAT). The cotton fiber used in this research as the carrier fiber was supplied by Cotton Incorporated, Cary, NC. The scoured and bleached commodity cotton fiber had a moisture content of 5.2%, a micronaire value of 5.4 and an upper-half-mean fiber length of 24.4 mm. Both the OCA and PCA binder fibers were provided by Celanese Corporation, Charlotte, NC while the Eastar and Eastar/PP bicomponent binder fibers selected for this study were produced by Eastman Chemical Company, Kingsport, TN. The plasticizer used in PCA binder fiber is triethyl citrate ester (C12H20O7) with a weight concentration around 2%. The bicomponent Eastar/PP has a sheath core structure with Eastar as the sheath and PP as the core. The properties of these selected fibers are listed in Table 10.3. 

One of the main uses of acetic anhydride is in the manufacture of cellulose acetate. Cellulose acetate is used in the production of plastics, coating chemicals, etc. Eastman Chemical Company has operated a highly successful rhodium-based acetic anhydride manufacturing process, based on the carbonylation of methyl acetate, for over 25 years. 

Magnesium acetate also has uses as a dye fixative in textile printing, as a deodorant, disinfectant, an antiseptic in medicine, and as a reagent chemical (see Disinfectants AND ANTISEPTICS Textiles) (6). In the United States, Hoescht-Celanese and Tennessee Eastman are the principal producers of magnesium acetate. These companies make about 36,000 t/yr, which is largely used in-house for the production of cellulose acetate. 

In a similar announcement, Eastman Chemical Co. and Rhc ne-Poulenc S.A. have recently formed a 50/50 joint venture to make 59,090 metric tons /yr of cellulose acetate filter tow and fiber by the fourth quarter of 1993 (107). Eastman Chemical Co. aimounced a multimillion doUar expansion of its own filter tow capacity by approximately 11,363 metric tons/yr to be completed by mid-1991. The expansion brings the company s worldwide filter tow capacity up to 154,545 metric tons (108). Eastman Chemical Co. aimounced plans to expand the production of cellulose acetate butryates and cellulose acetate propionates by 20 and 40%, respectively, by mid-1991 (109). 

The global supply of cellulose acetate fibers is controlled by a few companies. These companies produce both tow and textile fibers. Celanese Acetate holds 29% of the world supply. Voridian, a division of the Eastman Chemical Co., follows with a 24% share. The remaining 32% of supply is manufactured by Rhodia, Daicel, Mitsubishi Rayon, and Acordis. There has been a recent trend of these companies closing down their smaller flake-production units and getting their product from larger and more efficient locations (104). 

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