Adsorption of Phosphorous and Zinc, and their interaction and processing power on Bentonite

This work aimed to evaluate isothermic adsorption of Phosphorous and Zinc separately and their interaction on Bentonite minerals. Five concentrations of each element viz. 0, 50, 100, 150, and 200µgL^-1, and their interaction concentrations of 0+0, 50+50, 100+100, 150+150, 200+200µgL^-1 were used. Langmuier equation was used to calculate Xm and k. Estimating quantity and intensity curves (Q/I) and buffering capacity, as 2.5g of Bentonite was treated with increasing concentrations of P and Zn using K2HPO4 and ZnSO4.7H2O, respectively, 0, 0.2, 0.4, 0.8, 2 and 4mmol l^-1. The suspension was shaken for 3 hours and left for 24 hours to equilibrate, then the concentration of both P and Zn in the filtrate was extracted and estimated. The relationship between the quantity (adsorbed amount of e element) and the intensity (ionic activity) was drawn. From the slope of the straight line equation, the buffering capacity of the element was calculated. The results showed a significant increase in P and Zn adsorbed with the increase in levels of addition. Effect of interaction between two elements showed a significant increase in P adsorbed at the last two levels, whereas no significant increase was observed in addition of 50 and 100 µg ml^-1. The adsorbed Zn increased as a result of interaction between two elements. The value of Xm for adsorption of P was 114.94μg g^-1 in of adding P, and this value was not affected when P and Zn were added together. For Zinc, maximum adsorption capacity value in adding zinc alone was 204.08μg g^-1, and the value was similar in adding two elements together. Binding energy (k) was 0.056ml μg^-1 by adding P alone, and increased slightly when adding two elements together (0.081μg g^-1at adding Zinc), and binding energy was 0.005ml μg ^-1 and slightly increased when adding two elements together (0.006ml μg^-1). The adsorbed amount of Z. was higher than P and binding energy is lower. Buffering capacity of P in Bentonite was 13.28 mg P kg^-1 Bentonite, and it is considered an average with its P content whereas, Zinc had 341.84 mg kg^-1 considering mineral with a high Zinc content.