Isotherm parameters for basic dyes onto activated carbon: comparison of linear and non-linear method.

Equilibrium sorption experiments were carried out at 305 K with four different basic dyes basic red 9 (BR9), basic violet 3 (BV3), basic brown 1 (BB1) and basic violet 10 (BV10) onto activated carbon. The isotherm parameters were estimated linear and non-linear regression analysis. Non-linear method was found to be more appropriate method for estimating the isotherm parameters. The sorption capacity of activated carbon to uptake cationic dye ions in the increasing order was given by: BR9 (131 mg/g)< BV3 (247 mg/)< BV10 (259 mg/)< BB1 (404 mg/g).