Adsorption of Cu(II), Cd(II) and Pb(II) from aqueous single metal solutions by succinylated twice-mercerized sugarcane bagasse functionalized with triethylenetetramine

This study describes the preparation of two new chelating materials, MMSCB 3 and 5, derived from succinylated twice-mercerized sugarcane bagasse (MMSCB 1). MMSCB 3 and 5 were synthesized from MMSCB 1 using two different methods as described by Gurgel and Gil (2009). In the first method MMSCB 1 was activated with 1,3-diisopropylcarbodiimide and in the second with acetic anhydride (to form an internal anhydride) and later both were reacted with triethylenetetramine in order to obtain MMSCB 3 and 5. New obtained materials were characterized by mass percent gain, concentration of amine groups, FTIR, and elemental analysis. MMSCB 3 and 5 showed mass percent gain of 19.9 and 57.1%, concentration of amine groups of 2.0 and 2.1 mmol/g, and nitrogen content of 5.8 and 4.4%. The capacity of MMSCB 3 and 5 to adsorb Cu²⁺, Cd²⁺, and Pb²⁺ from aqueous single metal ion solutions was evaluated at different contact times, pHs, and initial metal ion concentrations. Adsorption isotherms were well fitted by Langmuir model. Maximum adsorption capacities of MMSCB 3 and 5 for Cu²⁺, Cd²⁺, and Pb²⁺ were found to be 59.5 and 69.4, 86.2 and 106.4, 158.7 and 222.2 mg/g, respectively.