Hydrolyzed starch graft copolymers of acrylic acid and acrylonitrile were used as a sorbents for the competitive removal of Pb (II), Cd (II) and Cu (II) ions from aqueous solution in batch process. The sorbents were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, wide-angle x-ray diffractometer and thermogravimetric analysis. The equilibrium sorption properties were assessed to optimize the conditions for maximum competitive sorption of the metal ions. The experimental data were subjected to sorption models: Langmuir, Freundlich, Temkin, Dubinin Radushkevich and Sips isotherm. The high coefficient of correlation (R2) of Freundlich and Sips confirmed the applicability of the models, which assumes strong interaction for the sorption of Cd2+, Pb2+ and Cu2+ onto the graft copolymers. Pseudo second order rate have proved suitable for highly heterogeneous systems of the sorption of Cu2+, Pb2+ and Cd2+ onto the graft copolymers The Gibb’s free energy change (ΔG0) values were found to be negative. Sorption affinity for the metals followed the order of Pb>Cu> Cd. No correlation was observed between metal affinity and its ionic or hydrated radii suggesting that size is not a significant factor for sorption of these heavy metals to the graft copolymers. This order suggested that electronegativity may be the most important factor as metal sorption increased with increasing electronegativity
LAWRENCE, E (2019). COMPETITIVE SORPTION OF Cd (II), Pb (II) AND Cu (II) IONS ON HYDROLYZED STARCH GRAFT COPOLYMERS. Afribary.com: Retrieved February 27, 2021, from https://afribary.com/works/competitive-sorption-of-cd-ii-pb-ii-and-cu-ii-ions-on-hydrolyzed-starch-graft-copolymers
EKEBAFE, LAWRENCE. "COMPETITIVE SORPTION OF Cd (II), Pb (II) AND Cu (II) IONS ON HYDROLYZED STARCH GRAFT COPOLYMERS" Afribary.com. Afribary.com, 20 Jun. 2019, https://afribary.com/works/competitive-sorption-of-cd-ii-pb-ii-and-cu-ii-ions-on-hydrolyzed-starch-graft-copolymers . Accessed 27 Feb. 2021.
EKEBAFE, LAWRENCE. "COMPETITIVE SORPTION OF Cd (II), Pb (II) AND Cu (II) IONS ON HYDROLYZED STARCH GRAFT COPOLYMERS". Afribary.com, Afribary.com, 20 Jun. 2019. Web. 27 Feb. 2021. < https://afribary.com/works/competitive-sorption-of-cd-ii-pb-ii-and-cu-ii-ions-on-hydrolyzed-starch-graft-copolymers >.
EKEBAFE, LAWRENCE. "COMPETITIVE SORPTION OF Cd (II), Pb (II) AND Cu (II) IONS ON HYDROLYZED STARCH GRAFT COPOLYMERS" Afribary.com (2019). Accessed February 27, 2021. https://afribary.com/works/competitive-sorption-of-cd-ii-pb-ii-and-cu-ii-ions-on-hydrolyzed-starch-graft-copolymers