Adsorptive removal of rhodamine B from textile wastewater using water chestnut (Trapa natans L.) peel: adsorption dynamics and kinetic studies

作者：Khan Tabrez A^*; Nazir Momina; Khan Equbal A

来源：Toxicological and Environmental Chemistry, 2013, 95(6): 919-931.

DOI：10.1080/02772248.2013.840369

• water chestnut peel waste
• rhodamine B
• adsorption
• kinetics
• thermodynamics

Water chestnut peel, an agricultural bio-waste, was used as a biosorbent for removal of rhodamine B (RhB), basic textile dye, from an aqueous solution. The effects of various experimental parameters were studied. The equilibrium data correlated well with a Freundlich isotherm (R-2 = 0.98-0.99) followed by a Halsey isotherm model (R-2 = 0.98-0.99) which indicated heterogeneity of the adsorbent surface and multilayer adsorption of RhB dye onto the water chestnut peel waste (WCPW). High correlation coefficients (R-2 = 0.99) together with close agreement between experimental q(e) (0.4-1.7mg g(-1)) and calculated q(e) (0.4-2.5mg g(-1)) suggested that the adsorption process followed pseudo-second-order kinetics, with k(2) values in the range of 52-3.4 x 10(-1) g mg(-1) min(-1) at different concentrations. The overall mechanism of adsorption was controlled by both liquid-film and intra-particle diffusions. The negative values of change in Gibb's free energy (-G(0) = 19.2-29.2 kJ mol(-1)) and positive values of change in enthalpy (H-0 = 30.9-117.6 kJ mol(-1)) revealed the process to be spontaneous and endothermic. WCPW was found to be an effective adsorbent for removal of RhB, a cationic dye, from an aqueous solution.

• 出版日期2013-7-1