ABSTRACT Peat water has a brownish red color because it contains high organic matter. Adsorption using zeolite as an adsorbent is one of the peat water treatment methods. POBA (Palm Oil Bottom Ash) is a solid waste from the disposal of oil palm boilers. POBA has a high silica content which can be used as a base for zeolite manufacture. The use of POBA as a low-cost adsorbent is one of the solu…