The purpose of this study was to characterize the Sidempuan’s salacca seed activated carbon using sodium carbonate (Na2CO3) activator with variations in activator concentration 0; 2.5; 5 and 7.5% by weight ratio of carbon: activator is 1: 10, the quality of activated carbon adsorbent Sidempuan’s salacca seeds was determined based on SNI (06-3730-1995). The best characterization of adsorbent…