Sorption studies of phthalic acid esters uptake from lagos lagoon sample using characterized gmelina arborea pericarp biosorbent

Abstract

ABSTRACT Organic chemical water pollutants, such as phthalic acid esters (PAEs), are toxic and harmful to living organisms and their removal is crucial. In this study, the analysis of the presence and quantity of PAEs in Lagos lagoon sample as well as its batch adsorption onto characterized Gmelina arborea Pericarp (GAP) as a low-cost biosorbent has been investigated. High-performance liquid chromatography was used for the analysis and quantification of PAEs in the lagoon sample. X-ray diffractometer, X-ray fluorescence, Fourier transformed infrared spectroscopy and scanning electron microscopy, respectively, were used for GAP characterization. The results showed that four out of six PAEs were detected in the sample. The GAP adsorbent is amorphous in nature, constituting less than 1% inorganic elements. The O-H, C-H, and C = O surface functional groups were attributed to stretching vibrations at 3324, 2922, 2855, and 1729 cm−1 while it morphologically has a spongy with alley-like porous surface. Experimental data fit best to Freundlich as well as Langmuir isotherm and pseudo-second order kinetics. The monolayer adsorption capacity of GAP is 94.9 mg/g (Langmuir model). The biosorption process was found to be endothermic and spontaneous, according to the thermodynamic parameters. The sample contains PAEs and GAP has been shown to be viable.