Sorption of melanoidin onto surfactant modified zeolite

Melanoidin is responsible for the dark brown color of distillery wastewater. Discharge of colored wastewater has a major environmental impact on the biota of the receiving water body. Consequently, this study explores the removal of melanodin
from aqueous solution. The equilibrium, kinetics and thermodynamics of melanoidin sorption are studied by varying initial solution pH, initial concentration, adsorbent dose and temperature. Kinetically, the melanoidin removal from solution by a surfactant modified zeolite is rapid and the amount adsorbed
is dependent on pH, initial concentration, adsorbent dose and temperature. The equilibrium sorption data are fitted to the Freundlich and Langmuir models
while the sorption kinetics are described by the Ho pseudo-second order and Elovich models. The thermodynamic analysis indicates that the sorption is
spontaneous and endothermic in nature. The FTIR spectra analyses show no new peaks or shift in peaks after sorption indicating that the melanoidin sorption may have occurred by a physical process. The results from desorption studies
showed that melanoidin eluted back easily to the solution using distilled water which corroborates the physical sorption mechanism.