Resumen
Contamination of water by
Pb
2
+
Pb
2
+
and the threat of invasive vegetation affects the quality and quantity of water accessible to all life forms and has become a primary concern to South Africa and the world at large. This paper synthesized, characterized, and evaluated the resins from tannin-rich invasive Acacia species as an environmentally benign
Pb
2
+
Pb
2
+
adsorbent. The analysis of the pore volume and surface area of the resins reveals a small pore dimension of 9
×
×
10-3 cc/g and large surface area (2.31?8.65 m2/g), presenting suitable physical parameters for adsorption of
Pb
2
+
Pb
2
+
. Langmuir model offers the best correlation data at pH 6 with maximum monolayer coverage capacity of 189.30, 105.70 and 98.82 mg/g for silver, black and green wattle tannin resins in aqueous solutions, respectively. The kinetic data suitably fits into a pseudo-second-order model, with the Dubinin?Radushkevich adsorption energy (E)
=
=
7.07 KJ/mol and intra-particle diffusion model confirming an associated physisorption process within the bio-sorption system. The thermogravimetric analysis (TGA) and Fourier-transform infrared (FT-IR) data of the resins were informative of the high thermal stability and chelating functionality such as -OH and -NH2 responsible for the removal of
Pb
2
+
Pb
2
+
. All the resins showed good adsorption characteristics while silver wattle tannin resin has the best adsorption capacity compared to black and green wattle tannin resins. This study provides a prototype adsorbent from invasive plants for the removal of
Pb
2
+
Pb
2
+
in water.