2.4. Characteristics of Filtration Media

Activated carbon has diverse surface characteristics and pore size distribution, and the characteristics of this activated carbon play an important role in the adsorption of contaminants. Activated carbon used in research is granular or irregular with a size of 0.2–5 mm. Activated carbon is obtained from coconut shell. The manufacturing process starts with the dehydration, the process of removing the water content from the raw material by heating it in an oven at a temperature of 170°C. At a temperature of around 275°C, carbon decomposition takes place and tar, methanol, phenol, and other by-products are formed. Nearly 80% of carbon is obtained at temperatures of 400–600°C. Charcoal was formed from carbonization at a temperature of more than 400°C, and activation was carried out chemically using calcium chloride (CaCl₂) [17, 18]. The mollusk sand used comes from the coastal area of West Kalimantan. Mollusk sand is the result of weathering the shell of the shellfish. Mollusk sand used is 0.2–5 mm in size.