Very strong carbon articles having high corrosion resistance - produced by polycondensation or oxidation of pitch and firing

摘要

Prodn. of very strong carbon articles having high corrosion resistance by subjecting petroleum- or coal pitch to a thermal polycondensation an oxidation to obtain a sinterable precursor material; moulding the latter under press. without any binder; baking the resulting articles and subjecting it to a high-temp. treatment; is improved in that the thermal treatment is carried out in the range 1200 to 2400 degrees C under such conditions that the product has a porosity =10% and the average pore dia. is 0.08-3 mu. This material has very high strength due to the absence of any binder. It has high resistance to corrosion esp. against attack by hydrofluoric acid. Therefore, this material is esp. suitable for use in apparatus for chemical processes involving use of hydrofluoric acid, as linings, packings, leads, bearings, condenser ribs, Raschig rings, filter plates, parts of heat exchangers, etc. The workability of this material is good.