The　effect　of　heat-treating　a　typical　activated　carbon　at　1600-2500　degreesC　on　its　structural　and　textural　properties　was　investigated　by　gas　sorption　and　X-ray　diffraction.　Particular　attention　was　paid　to　the　recovery　of　the　surface　area　and　porosity　of　thermally　treated　carbons　by　means　of　oxidation　treatments.　It　was　found　that　the　thermal　modification　of　activated　carbon　could　eliminate　carbon　impurities,　bring　about　different　degrees　of　graphitization,　and　improve　the　resistance　of　the　carbon　support　to　undergo　methanation　under　ammonia　synthesis　conditions,　but　the　surface　area　and　porosity　decreased　dramatically.　Oxidative　treatment　partially　recovered　the　surface　area　and　porosity.　The　higher　the　thermal　treatment　temperature,　the　greater　the　stability　of　the　carbon　support,　and　the　more　difficult　the　recovery　of　the　surface　area　and　porosity　becomes.　A　series　of　unpromoted　ruthenium/carbon　catalysts　showed　that　the　highly　developed　texture　of　the　carbon　support　resulted　in　a　significant　increase　in　Ru　dispersion.　The　ammonia　synthesis　activity　of　a　Ba-promoted　Ru　catalyst　was　greatly　improved　by　using　activated　carbon　C1900ox　as　a　support,　which　was　heated　at　1900　degreesC　in　an　inert　atmosphere　and　then　subjected　to　oxidation　treatment.　(C)　2002　Elsevier　Science　Ltd.　All　rights　reserved.