Investigation of Adsorption of Tetraoxosulphate (I) ions by Some Agricultural Soils in Akwa Ibom State, South-South igeria

Abstract

Authors: S. A. Odoemelam, I. U. Umoren, M. . Ogbuagu

Knowledge of adsorption capacity of different soils for sulphate ions is essential because it provide information on several background factors such as leaching, nutrient availability and others. In the light of this, we conducted a study to investigate the adsorption capacity of some selected agricultural soils (in Akwa Ibom State, Nigeria) for sulphate ions. Soil samples were collected from some agricultural zones spread within the state. Physicochemical properties of the soil were analysed using recommended methods while adsorption study was conducted using the batch adsorption experiment. Physicochemical properties of the soils were also determined. Maximum concentrations of SO₄^2- (mg/g) adsorbed by the five soils were 2260, 2245, 2160, 2110 and 1950 mg/g respectively. The Langmuir isotherms best fitted adsorption of sulphate ions by soils in some locations while Temkin and Van Huay isotherm best described sulphate ion adsorption in other locations. Pearson correlation analysis indicated that the Langmuir sorption maxima, Qmax, correlated negatively with available NO^3- (r = 0.769) but showed very strong positive correlation with silt (r = 0.840, P<0.05) and amorphous Al²O³ (r = 0.644), available NO^3– (r = 0.776)