Patent GB-717050-A (GB)
Title: Improvements in the manufacture of shaped carbon articles from bituminous materials
Inventor: POPPER FELIX BERTHOLD
IPC: C04B35/528
Filed: 1951-12-03
Abstract: Shaped carbon articles are manufactured by moulding or extruding a ground bituminous material having a predetermined volatile matter content of 15-35 per cent. and heating the shaped article to at least 600 DEG C. in a non-oxidizing atmosphere.  The bituminous material is coal tar pitch, petroleum bitumen or naturally occurring asphalt, but excluding coal.  The volatile matter content may be brought within the desired range by distillation at atmospheric, superatmospheric or reduced pressure, heating with a dehydrogenating agent, e.g. sulphur, treating with an oxidizing agent such as blowing with air or oxygen at 100-450 DEG C or by treatment with benzoylperoxide, or any of these treatments in combination, or in combination with a treatment with polymerization catalysts, e.g. aluminium chloride, or condensation with formaldehyde.  The bituminous material may be mixed with agglutinating agents, e.g. up to 10 per cent. sulphur, metal or metal oxide such as iron, copper, nickel, or iron oxide when it should be ground to 90 per cent. pass 100 B.S.S.  If no agglutinating agent is added the bituminous material should be ground to 90 per cent. pass 50 B.S.S.  The finely divided material is packed tightly in a metal former or moulded in a press, e.g. at below 5,000 lbs./sq. in.  The shaped article is embedded in finely ground coke in a muffle furnace and may be fired at above 1,000 DEG C. depending on the application.  The temperature increase during firing should be not less than 0.25 DEG C. per min. for large articles or 2 DEG C. per min. for smaller.  The articles may be made porous, where up to 50 per cent. metal or metal oxide agglutinating agent is used by treatment with hydrochloric or acetic acids.  The carbon articles may be structural materials, refractories, ceramics, electrodes, carbon brushes, or porous filters.ALSO:Shaped carbon articles are manufactured by moulding or extruding a ground bituminous material having a predetermined volatile matter content of 15-35 per cent. and heating the shaped article to at least 600 DEG C. in a non-oxidizing atmosphere.  The bituminous material is coal tar pitch, petroleum bitumen, or naturally occurring asphalt, but excluding coal.  The volatile matter content may be brought within the desired range by distillation at atmospheric, superatmospheric or reduced pressure, heating with a dehydrogenating agent, e.g. sulphur, treating with an oxidizing agent such as blowing with air or oxygen at 100-450 DEG C. or by treatment with benzoyl peroxide, or any of these treatments in combination, or in combination with a treatment with polymerization catalysts, e.g. aluminium chloride, or condensation with formaldehyde.  The bituminous material may be mixed with agglutinating agents, e.g. up to 10 per cent. sulphur, metal or metal oxide such as iron, copper, nickel, or iron oxide, when it should be ground to 90 per cent. pass 100 B.S.S.  If no agglutinating agent is added, the bituminous material should be ground to 90 per cent. pass 50 B.S.S.  The finely divided material is packed tightly in a metal former or moulded in a press, e.g. at below 5000 lbs./sq. in.  The shaped article is embedded in finely ground coke in a muffle furnace and may be fired at above 1000 DEG C. depending on the application. The temperature increase during firing should be not less than 0.25 DEG C. per min. for large articles or 2 DEG C. per min. for smaller. The artcles may be made porous, where up to 50 per cent. metal or metal oxide agglutinating agent is used by treatment with hydrochloric or acetic acids.  The carbon articles may be structural materials, refractories, ceramics, electrodes, carbon brushes, or porous filters.