A200 pitch

Analyses of these coals and of the A200 pitch are in Tables IV and V ... 

Firstly, co-carbonization of anthracites (CR 101) with A200 gives a coke showing two distinct types of anisotropy or phases. One phase is coke from the anthracite not modified by the A200 pitch and which shows basic anisotropy. The other phase is coke from the A200 pitch (flow domain anisotropy) which appears to act as a binder. 

Secondly, for high rank low volatile caking coals (CR 203-204), cokes produced with 25% A200 pitch also show two phases or types of anisotropy but with no sharp boundary between the two. Optical texture progressively decreases in size from the flow... 

Figure 7. Point-counting analyses of optical textures of cokes. Key a, Blaen-hirwaun Pumpquart vitrain (N.C.B. rank 101) and b, Blaenhinvaun Pumpquart vitrain + 25% A200 pitch.

Fourthly, A200 pitch when co-carbonized with high volatile caking coals (CR 601-701) almost completely modifies the isotropic texture of the coal coke to give an optical texture predominantly of medium-grained mosaics. Again, the optical texture is uniform rather than having two phases. 

Grint, A. Swietlik, U. Marsh, H. Carbonization and Liquid-crystal (Mesophase) Development-9. The Co-carbonization of Vitralns with Ashland A200 Petroleum Pitch. Fuel, 1979, M,... 

Ashland A200 petroleum pitch. Ashland A170 pitch coke (green). 

Thirdly, when A200 is blended with prime coking and medium volatile caking coals (CR 301-501) the resultant coke shows an increase in size of optical texture compared to that of the coal coke when carbonized singly. This new optical texture is intermediate in size between that of the coal coke and pitch coke. 

Figure 5.25. Scanning electron micrograph of surface of a graphitizable carbon from Ashland A200 petroleum pitch HTT 1223 K, oxidized in carbon dioxide to 40 wt% bum-off at 1123 K.

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