Aqueous Phase Adsorption of Pb (II) Ions onto Hymenoptera sphecidae (Mud-wasp) Nest
Donald T. Kukwa *
Department of Chemistry, Benue State University, Makurdi, Nigeria.
Peter A. Adie
Department of Chemistry, Benue State University, Makurdi, Nigeria.
Rose E. Kukwa
Department of Chemistry, Benue State University, Makurdi, Nigeria.
Paula D. Kungur
Department of Chemistry, Benue State University, Makurdi, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Removal of Pb (II) ion from aqueous solution using Hymenoptera sphecidae (mud-wasp) nest was investigated using a batch process. The effect of pH, contact time and adsorbent dose were also investigated. The result showed that the adsorption of Pb (II) ion onto mud-wasp nest was dependent on pH, contact time and adsorbent dose. Adsorption patterns were analysed in terms of three bi-parameter isotherms of Langmuir, Freundlich and Temkin. Freundlich isotherm gave the best fit to the adsorption data with a correlation coefficient of 0.992, while monolayer sorption capacity yielded 41.667 mg/g. Lagergren’s pseudo first-order and pseudo second-order kinetic models were used to test the adsorption kinetics. The kinetic data were well described by the pseudo second-order kinetic model, suggesting that the process was chemisorption type. The results showed that mud-wasp nest can be used as a low-cost adsorbent for the removal of Pb (II) ion from aqueous solutions.
Keywords: Lead (II) ions, adsorption isotherms, kinetic models, mud-wasp nest