Activated carbonaceous honeycomb body and production method thereof

A method for producing an activated carbonaceous honeycomb body which comprises:

• extruding a mixed and kneaded mass containing a phenol resin into a honeycomb structure at an extrusion pressure of 90 kg/cm.sup.2 or higher and at a linear extrusion velocity of 5 mm/sec or faster to obtain a green honeycomb body;
• allowing the green honeycomb body to stand for at least 5 hours;
• after drying and solidifying the green honeycomb body, preheating the thus-dried and solidified green honeycomb body in a non-oxidizing atmosphere to a temperature in the range of from 500.degree. to 1,100.degree. C. and holding it within the preheating temperature range until the hydrogen content of the resulting C-matrix thereof has been lowered to 2% or less;
• cooling the thus-preheated honeycomb body at a cooling rate of 50.degree. C./hr or lower to a temperature 100.degree. C. below the final holding temperature and then at a cooling rate of 100.degree. C./hr or lower;
• and
• heating again the thus-cooled honeycomb body in an activating atmosphere to a temperature in the range of from 600.degree. to 1,000.degree. C. and holding the same within the heating temperature range until the ratio of the total thickness of resulting activated carbon layers to that of the remaining glassy carbon layer in the thickness direction of each wall of the honeycomb body has reached a value not greater than 30.