The　thermal　desorption　technique　has　been　explored　experimentally　to　remove　mercury　from　the　gold-loaded　granule　activated　carbon　(GAC)　co-adsorbed　during　heap　leaching　of　gold　ores　bearing　mercury.　The　effects　of　treatment　temperature,　retention　time　and　flow　rate　of　steam　used　as　purge　gas　on　residual　mercury　levels　were　investigated.　Characterization　techniques　such　as　N　2　adsorption-desorption,　X-ray　powder　diffraction　and　X-ray　photoelectron　spectroscopy,　were　employed　to　understand　how　thermal　treatment　affects　the　gold　elution　in　a　caustic　cyanide-free　eluant　from　the　treated　GAC.　The　results　showed　that　mercury　desorption　was　strongly　affected　by　the　treatment　temperature　and　steam　flow　rate.　Treatment　for　3　h　at　550°C　under　steam　atmosphere　with　0.4　m3/h　flow　rate　was　allowed　to　remove　more　than　99.78%　mercury　and　the　content　of　residual　mercury　in　the　treated　GAC　was　decreased　to　0.035　g/kg,　likely　reaching　the　thresh　level　of　mercury　extraction　during　gold　elution　in　a　caustic　cyanide　eluant.　Meanwhile,　activated　carbon　was　partially　regenerated,　with　only　4.06%　weight　loss　of　carbon,　mainly　due　to　microporosity　recovery.　However,　it　was　observed　that　the　thermal　process　would　have　heavily　influenced　elution　of　gold　from　the　treated　activated　carbon　in　a　caustic　eluant　without　sodium　cyanide.　This　phenomenon　has　been　attributed　primarily　to　the　change　of　chemical　state　of　gold　species　and　accumulation　of　highly　dispersed　gold　species　and　even　formation　of　more　stable　gold　nano-particles　caused　by　a　combination　of　promotion　of　high　temperature　and　steam　oxidation.　The　elution　of　gold　from　the　treated　sample　could　be　improved　through　introduction　of　NaCN　into　the　caustic　eluant.　However　only　83.84%　of　gold　was　eluted,　probably　because　the　elution　time　was　insufficient.　©　2012　Elsevier　B.V.