GB927857A - Anti-corrosion material - Google Patents

Abstract

An anticorrosion material comprises high-grade pitch, with or without fillers, and at least one solid, crystalline aromatic compound containing at least three rings in its chemical structure (but excluding chlorinated polyphenyls), in an amount between 12% and 50% by weight of the pitch, and greater than that required to obtain a saturated solid solution of the compound(s) in the pitch. High-grade pitch is defined as being obtained by fluxing coal tar hard pitch with coal-tar oil; to this, a mixture of coal dust and coal tar oil may be added. Alternatively, raw coal-tar is distilled to remove the middle oil, and blown with air or other oxygen-containing gas, to provide high-grade pitch. The aromatic compound may be anthracene, phenanthrene, or carbazole or a mixture thereof, e.g. as obtained by cooling anthracene oil. In another embodiment, pitch-like material, viz., petroleum bitumen or asphalt, or both, with or without high-grade pitch, is mixed with an aromatic compound as above, in an amount between 5% and 50% by weight of the pitch-like material, and greater than that required to give a solid solution of the compound in the pitch-like material.ALSO:An anti-corrosion material comprises high-grade pitch, with or without fillers, and at least one solid, crystalline aromatic compound containing at least three rings in its chemical structure (but excluding chlorinated polyphenyls), in an amount between 12% and 50% by weight of the pitch, and greater than that required to obtain a saturated solid solution of the compound(s) in the pitch. High grade pitch is defined as being obtained by fluxing coal tar hard pitch with coal tar oil; to this, a mixture of coal dust and coal tar oil may be added. Alternatively, raw coal-tar is distilled to remove the middle oil, and blown with air or other oxygen-containing gas, to provide a high-grade pitch. The aromatic compound may be anthracene, phenatthrene or carbazole or a mixture thereof, e.g. as obtained by cooling anthracene oil. In another embodiment, pitch-like material, viz., petroleum bitumen or asphalt, or both, with or without high-grade pitch, is mixed with an aromatic compound as above, in an amount between 5% and 50% by weight of the pitch-like material, and greater than that required to give a solid solution of the compound in the pitch-like material.