Patent ID: 7662747

Claim:
A process for producing granular activated carbon by carbonization of suitable carbonaceous polymers in the form of polymer granules as a starting material, which polymer granules are convertible by carbonization into carbon, wherein the polymer granules are continuously moved through a carbonization apparatus comprising a plurality of temperature zones so that a complete conversion of the starting material to carbon is effected, wherein the carbonization apparatus comprises at least the following temperature zones in the following order: a) a first temperature zone (“sulfonating zone”) where in the case that the starting material contains no groups which, when thermally decomposed, lead to free radicals and thus to cross-linkages or else in the case that such groups are to be additionally introduced into the starting material, these groups are introduced into the starting material; then b) a second temperature zone (“pre-carbonization zone” or “zone of acidic gases”), the second temperature zone having a higher average temperature than the first temperature zone, wherein in the second temperature zone the groups which, when thermally decomposed, lead to free radicals and thus to cross-linkages are split off from the starting material, so that carbonization and thermal decomposition of the starting material ensues, accompanied by crosslinking of the polymers and formation of carbon; and then c) a third temperature zone (“post-carbonization zone”), the third carbonization zone having a higher average temperature than the second temperature zone, wherein in the third temperature zone further carbonization of the starting material resulting from the second temperature zone is performed, so that a complete conversion of the starting material to carbon is effected; wherein the individual temperature zones are separately and independently controlled.