Based　on　the　steam　gasification　experiments　of　＇Fujian　Jianxin＇　anthracite　with　different　catalyst　loadings　of　Na2CO3　in　the　thermal　balance　at　850°C,　decomposition　of　Na2CO3　itself　and　mass　loss　arising　from　the　reaction　of　Na2CO3　with　carbon　in　coal　were　examined.　Also,　the　change　of　adsorption-desorption　isotherms　of　coal　samples　at　different　conversions　were　measured　with　the　specific　surface　area　analyzer.　Type　I　adsorption-desorption　of　a　narrow　slit　micropore　configuration　with　a　close　end　was　mainly　shown　at　a　lower　Na2CO3　loading　and　lower　conversions,　while　type　II　adsorption-desorption　of　open　mesopores　and　macropores　with　two-end　opening　holes　was　formed　at　a　higher　Na2CO3　loading　and　higher　conversions.　H4-type　hysteresis　loop　with　slit　and　ink-bottle　pore　surface　appeared　at　and　beyond　the　catalyst　saturation　loading　of　12%　Na2CO3.　The　specific　surface　area　and　pore-size　distribution　at　different　Na2CO3　loadings　and　conversions　were　calculated　using　BET　equation　and　T-plot　model.　These　calculation　indicated　that　all　of　specific　surface　area　appeared　to　be　increasing　at　first　then　decreasing　with　increasing　conversion　extent　of　coal.　The　split　and　crosslinking　of　more　micropores　and　the　reduction　of　micropore　specific　surface　area　were　the　result　of　the　increase　of　active　sites　of　carbon　and　gasification　rate　due　to　the　loading　and　dispersing　of　Na2CO3　catalyst.　The　change　of　specific　surface　area　with　increasing　at　first　then　decreasing　became　more　smooth　with　more　loading　of　Na2CO3.　At　the　catalyst　saturation　loading　of　12%　Na2CO3,　the　sufficient　filling　and　uniform　dispersion　of　catalyst　led　to　increase　of　active　sites　on　micro-crystalline　structure　surface　of　more　inert　carbon　and　the　split　and　crosslinking　expansion　of　more　micropores　in　the　gasification　process.　However,　at　the　termination　gasification　reaction　with　deep　conversion,　all　of　specific　surface　area　were　close　to　zero,　clearly　showing　maximum　conversion　of　coal　and　uniform　gasification　at　catalyst　saturation　loading.　©　2012　All　Rights　Reserved.