Making chitosan coating active charcoal is similar to that done by Nomanbhay and Palanisamy (2005). Fifteen
gram active charcoal was entered into 15 ml gel chitosan 1% (1g chitosan in 100 ml oxalate acid 10%) and the mix
was shaken with shaker for 24 hours. Ratio of 15 ml gel chitosan 1% and 15 g active charcoal is considered 1:1 that
coded with K1A1. The mixture was filtered, washed with distilled water and dried. coating process was repeated
three times to obtain thick chitosan on active charcoal. Chitosan-layered active charcoal was separated from solution
and soaked in 0.5% NaOH for 3 hours for neutralization and filtered and washed with distilled water to obtain
neutral substrate. The active charcoal is dried at 600C and resulted in constant weight. Similar procedure was done
for 15 ml gel chitosan 2%:15 g active charcoal with 2:1 ratio (K2A1) and 15 ml gel chitosan 3%: 15 ml active
charcoal with 3:1 ratio (K3A1).