Agustin, Jumbri2021-10-212021-10-212021-05wahyu sari yenihttps://repository.unri.ac.id/handle/123456789/10305Rubber seed shells (Hevea brasiliensis) contain fiber and various carbon compounds such a selulose, hemicellulose and lignin which are potentially used as adsorbents. In this study, rubber seed shells was carbonized at 500°C for 15 minutes and activated with H3PO4 activator. Various concentrations that used for addition of activator are 5; 10;15% to found the best conditions. Charcoal produced was characterized to determine water content, ash content, and iodine absorption. Rubber seed shell charcoal was activated by H3PO4 10% was the best condition and had characteristics a water content of 0,89%; ash content of 0,24%, iodine absorption 829,77 mg L-1. Rubber seed shell activated charcoal was applied for post-coagulation peat water treatment with variations of mass (1,0; 1,5; 2,0) g and contact time 15 minutes. The best condition of peat water adsorption was obtained at dose of 1,5 g (A1,5) with a percentage of color removal 97,07%. Rubber seed shell charcoal activated by H3PO4 10% has been able to improve the parameter of color, in accordance with PERMENKES RI No.32 of 2017.enactivated charcoaladsorptionpeat waterArticle