GB1107590A - Graphite body - Google Patents

Abstract

A graphite body having a relatively high and substantially isotropic coefficient of thermal expansion is produced by maintaining a petroleum residue above its melting point, contacting the residue with a free oxygen-containing gas until the melting point of the residue is raised to at least 150 DEG C., coking the treated residue at 450 DEG to 650 DEG C., calcining the resulting coke at 900 DEG to 1500 DEG C., comminuting the calcined coke, admixing the comminuted coke with a carbonizable aromatic binder, forming the admixture into a desired shape, carbonizing the binder in the shaped body in an inert atmosphere and graphitizing the body at 2600 DEG to 3000 DEG C. in an inert atmosphere. The "petroleum residue" consists of the residues from the vacuum or atmospheric distillation of crude oil and the free oxygen-containing gas may be air, which may be blown through the residue at 30 to 50 s.c.f. per minute per ton of residue, which may be agitated and maintained at 260 DEG to 300 DEG C. Preferably the blowing treatment is continued until the melting point of the residue is at least 225 DEG C., the coking is carried out at 450 DEG to 525 DEG C. and the binder is carbonized at 750 DEG to 1000 DEG C. Oxygen, oxygen-enriched air or a mixture of oxygen and argon are other suitable gases. Coal tar pitch, petroleum pitch and wood pitch are suitable binders.ALSO:A graphite body having a relatively high and substantially isotropic coefficient of thermal expansion is produced by maintaining a petroleum residue above its melting point, contacting the residue with a free oxygen-containing gas until the melting point of the residue is raised to at least 150 DEG C., coking the treated residue at 450 to 650 DEG C., calcining the resulting coke at 900 DEG to 1500 DEG C., comminuting the calcined coke, admixing the comminuted coke with a carbonizable aromatic binder, forming the resulting admixture into a desired shape, carbonizing the resulting binder in the shaped body in an inert atmosphere and graphitizing the body at 2600 DEG to 3000 DEG C. in an inert atmosphere. The "petroleum residue" consists of the residues from vacuum or atmospheric distillation of crude oil and the free oxygen containing gas may be air which may be blown through the residue at 30 to 50 s.c.f. per min. per ton of the residue, which may be maintained at 260 DEG to 300 DEG C. with agitation. Preferably the blowing treatment is continued until the melting point of the residue is at least 225 DEG C., the coking carried out at 450 DEG to 525 DEG C. and the binder carbonized at 750 DEG to 1000 DEG C. Oxygen, oxygen-enriched air, or a mixture of oxygen and argon are other suitable gases. Coal tar pitch, petroleum pitch and wood pitch are suitable binders.