UPGRADING OF PITCH PRODUCED BY MILD GASIFICATION OF SUBBITUMINOUS COAL

Alternative sources of anode binder pitch may be required in the futur e. One potential process for the production of pitch is low-temperatur e coal pyrolysis or mild gasification. Characterization data for a pit ch produced by mild gasification of Powder River Basin subbituminous c oal are reported. This pitch has acceptable sulfur, sodium, ash, and b eta-resin levels but is shown to be deficient in aromatic carbon conte nt and quinoline insolubles (QI). It also contains high levels of oxyg en which leads to a high softening point and low coking value. Several strategies for upgrading this pitch to meet anode binder standards we re investigated. These included heat treating, air blowing, solvent ex traction, vacuum distillation, and addition of artificial QI. The addi tion of artificial QI (carbon lampblack) was the most successful of th e methods investigated.