the effect of binder pitch quinoline insolubles content - Coke Oven ...

BINDER PITCH QI CONTENT – ALUMINIUM ANODE
Although a number of different “ideal” ranges are given in the
literature for normal QI levels [4,13,14,21,28], however most of
these are based on historical results. As normal QI levels have come
down, so has the bottom limit of the ideal ranges – when put to the
test, the lower normal QI pitches have performed acceptably.
The situation is well described in [4]: “The importance of normal QI
in binder pitch is well established. However, there is some
disagreement as to the optimal content” and “……..the amount of
normal QI must be consistent”
The anode study conducted did not reveal anything that would
contradict the concept that acceptable anodes can be produced with
pitches with as little as 3.9 wt. % normal QI. The lower Baked
Apparent Density at lower normal QI levels warrants further
attention as there is potential to improve this through modification of
the anode formulation process [5].
References
1 T. Foosnaes & T Naterstad, Carbon: basics and principles, In
Introduction to Aluminium Electrolysis, 2 nd Ed. (Aluminium
Verlag, Dusseldorf, 1993), 87 – 134.
2 H. Marsh, Carbon anodes for Aluminium – Manufacture,
Structure and Properties, Proc. CIM Annual Conference of
Metallurgists, 1986, 63 – 86.
3 R. Gray & K. Krupinski, Pitch Production, In Introduction to
carbon technologies (Alicante: Universidad,1997), 329 – 424
4 K. Krupinski & J. Windfelder, Effects of tar Quinoline
Insolubles on manufactured carbon performance, Proc.
Ironmaking Conference, 1992, 487 – 492.
5 K. Hulse, Anode Manufacture – raw materials, formulation and
processing parameters, PhD Thesis Univ. of Auckland, New
Zealand, (R&D Carbon Ltd, Sierre, Switzerland), 2000.
6 W. Roder, The future of coal tar pitch and alternative pitches for
carbon electrodes, CIM Light Metals 1998, 1998 171 – 182.
7 A. Mirchi, G. Savard, J-P, Tremblay, & M. Simard, Alcan
characterization of pitch performance for pitch binder evaluation
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