Übersetzung für "Coal tar pitch" in Deutsch

A very abrasion-resistant spherical activated charcoal can be produced, for example, from coal tar pitch or petroleum distillation residues.

Coal-tar pitch is extracted with hot chloroform and the pitch solution treated with solid iodine.

Carbon graphites are created by combining the two forms of carbon with coal tar pitch.

Coal tar pitch is a natural product, which varies in its specific composition.

The present invention relates to a new coal tar pitch and a process for the preparation and use thereof.

Under the high application temperatures in the metallurgical vessels, the binders phenolic resin and coal-tar pitch are carbonized to form carbon.

Following the moulding operation, the parts are sintered at temperatures high enough to carbonise the coal tar pitch.

Work involving exposure to polycyclic aromatic hydrocarbons present in coal soot, coal tar or coal pitch.

The Committee supports Point 4 of the amendment which resolves problems in interpretation which led in some States to the incorrect inclusion of coal dust, with coal soot, coal tar and coal pitch in the definitions Annex 1 List of Substances, Preparations and Processes work involving exposure to aromatic polycyclic hydrocarbons.

Soederberg anodes are baked in the cell, with a mixture of petroleum coke and coal tar pitch acting as a binder.

Moreover, the fractionation of coal-tar pitch by means of picric acid as a method of analysis has been described (Compendium 77/78, Supplementary Volume, Oil & Gas, Natural Gas, Petrochemistry, pages 235-251, in German).

Therefore, there remained the task of developing a method of extracting a highly reactive pitch fraction which can be converted quickly even at low temperatures into a high-anisotropic carbon and which can be obtained in high yields from coal-tar pitch.

Various investigations have shown that coal tar pitch contains polycyclic aromatic hydrocarbons which can escape in a gaseous form during production and/or use of refractory linings and self-calcining electrodes.

DETAILED DESCRIPTION In contrast to coal tar pitch, bitumen contains polycyclic aromatic hydrocarbons only in extremely low concentrations which are non-hazardous for the health of industrial employees.

On using such a paste for Soederberg anodes one finds that within 5 weeks a bitumen liquid deposit rises and forms on the surface of the anode, as can occur when using coal tar pitch.

Otherwise, the use of soft bitumen for binder, in the same amounts as coal tar pitch, leads to a low dry residue and thus to high porosity and inadequate bonding of the solid particulate material.

In view of the known low level of dry residue when using about 38 wt % bitumen instead of about 50-60 wt % coal tar pitch the expert in the field has up to now assumed that it is basically inappropriate to use bitumen as a binder for the production of carbon pastes for self-calcining electrodes, especially Soederberg anodes and refractory linings, in furnaces and crucibles and connections for electrode joining points.