Coal tar pitch blend having low polycyclic aromatic hydrocarbon content and method of making thereof

摘要

A coal tar pitch/petroleum pitch blend is disclosed together with a method of making the same. In accordance with the invention, a crude coal tar material is selected according to specific properties including QI, specific gravity, water and ash content. A petroleum pitch material is also selected according to its softening point, QI, coking value and sulfur content. The coal tar pitch is distilled to a uncharacteristically high softening point which is then mixed with the petroleum pitch to a desired softening end point. The material retains significant QI and coking value characteristics of pure coal tar pitch particularly for use in Soderberg-type anodes for aluminum smelting as well as electric arc furnace electrodes. PAH emissions, and more specifically B(a)P equivalent emissions, are all reduced by approximately 40%.