Amoco carbons

Figure 12.1. Adsorption-desorption isotherms of (a) nitrogen at 77 K, (b) toluene at 20°C and (c) water at 21°C, on AMOCO carbon PX21 (A) and charcoal cloth AM4 (Q (Atkinson et al., 1982).

In their adsorption properties, carbon cloth samples JF516 and JF518 appear to be somewhat similar to the AMOCO carbon PX21 Also, we note the intermediate nature of the two samples JF142 and JF144 These and many other adsorption measurements confirm that it is now possible to produce a wide range of activated carbons in stable cloth-form with remarkably well-controlled pore structures... 

Thomel Carbon Fiber. [Amoco] Carbon fibers. 

Table 20.16 Computed carbon fiber properties of some Amoco carbon fibers based on...

The anisotropy of the basic carbon and aramid fibres is clear as is the high longitudinal thermal conductivity of the very high modulus Amoco carbon fibres. 

Producers of PAN-based carbon fiber include Toray, Toho Beslon, Mitsubishi Rayon, and Asahi Kasai Carbon in Japan Hercules, Amoco Performance Products, BASE Stmctural Materials, Eortafil (Akzo), and Mitsubishi Rayon in the United States and Akzo, Sigri, and Soficar in Europe. Primary suppHers of high performance pitch-based carbon fibers include Amoco Performance Products, Mitsubishi Kasai, and Tonen Corp. 

Mechanical Properties and Stability at Elevated Temperature. One increasingly important characteristic of carbon fibers is their excellent performance at elevated temperatures. Strength tested in an inert environment remains constant or slightly increases to temperatures exceeding 2500°C. Amoco s high modulus pitch carbon fiber P-50 maintains approximately 80% of room temperature modulus at temperatures up to 1500°C, then decreases more rapidly to 30% at 2800°C (64). The rapid decrease in modulus is a result of increased atomic mobiHty, increa sing fiber plasticity. 

Although several companies have produced polyarylates, Unitika in Japan and Hoechst-Celanese are the only ones active in the marketplace. Unitika resin is marketed in the United States by Amoco Performance Polymers under the Ardel trademark. The reason for this decline may be the competition of PC, polyester carbonates, and polysulfone resins. Worldwide sales are quite small, probably less than 1000 t/yr. 

Blends of the polysulfone tesia have been made with ABS, poly(ethylene terephthalate), polytetrafluoroethylene (PTFE), and polycarbonate. These ate sold by Amoco under the Miadel trademark. Additional materials ate compounded with mineral filler, glass, or carbon fiber to improve properties and lower price. 

Milled (200 >um length) mesophase piteh-derived carbon fibers were purehased from Amoco Performance Products, Inc., Alpharetta, Ga., under the designation DKDX fibers. 

Tabic 3. Some Studies on Methane Storage using Amoco Type KOH Activated Carbon Adsorbents... 

Carbon Highly graphitic carbon fiber PI 00 (Amoco), 1st charge with -50 pA mg 1 [4],... 

Figure 5. Integrated capacity losses of LiCn in PC electrolytes without and with electrolyte additives (CO2, N2O, S ). Electrolyte 0.5 M UCIO4 inPC, Carbon Highly graphitic carbon fiber PI00 (Amoco), i = 50 pA mg1, cut-off 0-2 V vs. Li/Li+ [4],...

Figure 7. Constant current charge/discharge cycling ofhighly graphitic carbon fiber P100 (Amoco) in 1.8 MLiAlCl4 in SOCl2 electrolyte, i = 300 pA mg 1, cut-off 0-2V vs. Li/Li+ [4],...

As outlined above a purity of only 99.5% is not sufficient for a polymer feedstock and the mono-acid intermediate has to be removed either by oxidation under more forcing conditions (Mitsubishi) or reduction (Amoco). In the Amoco process (not shown) the crude di-acid is dissolved in water (275 °C) (15 % weight) and hydrogenated over a palladium on carbon catalyst. The intermediate 4-formylbenzoic acid is hydrogenated to 4-toluic acid which has a much higher solubility and does not cocrystallise with terephthalic acid. The solution is carefully cooled while the product crystallises and the by-product remains in the water. The final content of 4-formylbenzoic acid is as low as 15... 

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