Geopolymer based on kaolin was used for adsorbent in this research to remove ferrum and manganese from peat water with adsorption process. Geopolymer is kind of syinthetic compound which made by synthesizing alumino and silicate materials and known have similarity with zeolit. The variables used in this research are ratio alkaline activator per kaolin to made goepolymer and adsorbent dosage to …