International Journal of Research and Scientific Innovation (IJRSI) | Volume IX, Issue VI, June 2022 | ISSN 2321–2705
Non-Linear Sorption Isotherm and Kinetic Studies of Pb2+ on Poly(1-phenylethene-1,2-diyl) Waste Adsorbent
C. W. Dikio1, C. Y. Abasi2*, O. Benson2*, D. Wankasi2, E. D. Dikio2
1Applied Chemistry and Nano-science Laboratory, Department of Chemistry, Vaal University of Technology, P. O. Box X021 Vanderbijlpark 1900, South Africa
2Department of Chemical Sciences, Niger Delta University, Wilberforce Island, P.M.B. 071, Yenagoa Bayelsa State, Nigeria
*Corresponding Author
Abstract: The sorption of Pb2+ on waste poly(1-phenylethene-1,2-diyl) adsorbent has been investigated. Batch equilibrium and kinetic adsorption experiments were done to determine the effects of concentration and contact time respectively. Data analysis was carried out using the non-linear isotherms and kinetic models. Non-linear isotherm parameters showed high consistency with those of the linear. The rate studies showed that the controlling kinetics was pseudo second order. Chi-squared (χ2) statistics was also applied for the best fitting model between closely competing correlation values of Langmuir and Freundlich models. Chi-squared (χ2) statistics showed that Freundlich model described the sorption better than the Langmuir isotherm. The prevalence of Freundlich over Langmuir from correlation and validity tests indicated a multilayer adsorption. Diffusion analysis showed that intraparticle diffusion was not the prevailing mechanism for the adsorption.
Keywords: Sorption, non-linear, poly(1-phenylethene-1,2-dial), adsorbent, isotherm, polymer, physisorption.
I. INTRODUCTION
The increasing diversification in industrialization and urbanisation has contributed to the existence of heavy metals such as lead (Pb) in the aqueous environment, with a noticeable threat to living organisms (animals, humans and plants) as a result of their bio-accumulating propensities and toxicity[1]. Some specific sources of Pb2+ in our environment include automobiles, batteries, paints, textile and petroleum industries, etc. [2],[3]. The elimination of these toxic heavy metals from urban and industrial wastes prior to their summary release into the environment has therefore, become essential.
Conventional heavy metal removal techniques such as reverse osmosis, filtration, precipitation, flocculation and ion exchange are very expensive. However, there have been cheaper and more renewable materials used to remove metal ions from wastes. These include biomasses like Seaweed [1], Medicago sativa [2], Manihot esculenta Crantz [3] and Nipa palm[4].