DIALYSIS MEMBRANE TUBE FILLED WITH Fe-Al-Zr TERNARY MIXED OXIDE NANOCOMPOSITE: SYNTHESIS, CHARACTERIZATION AND PHOSPHATE DESORPTION STUDY FROM ACID SOILS

Abstract

Phosphorus fixation with different soil components is the main problem making it less available to plants. To approximate this biological measure, a method comprising of Fe-Al-Zr mixed oxide filled DMT was developed in this study. For this purpose, Fe-Al-Zr ternary mixed oxide nanocomposite adsorbent with 60, 25 and 15 percentage composition of Fe, Al and Zr, respectively, was synthesized via impregnation method. The as-synthesized adsorbent was characterized by XRD, BET, SEM-EDX, FT-IR and FAAS analytical instruments. Its crystal size and surface area were found to be 29.59 nm and 107.53 m 2 /g, respectively. The phosphate desorption study was conducted using the method developed in this study from four soil samples which received different P treatments (0, 50,100 and 150 mg kg-1 ) for 28 days of desorption time and the phosphate desorption from soil to plant was predicted. The results suggest that the phosphorus treatment and desorption time had significant effect on the amount of desorbed phosphorus from the soil samples. That means low (0.71-13.41 mg kg-1 ) P was desorbed from control and higher (1.87-27.84 mg kg-1 ) P from 150 mg kg-1 P treated soil at all levels of extraction time (1-28 days) for all soil samples. The rate of desorption of P through DMT was found to be 0.0315 hr-1 and was low as compared to other findings which implies the soil samples in this study were highly acidic and high phosphorus fixing soil. The physicochemical properties like pH-KCl, Av.P, TP, FeDCB, MnDCB and FeAAO were highly correlated with desorbed phosphorus. Generally, the present study attempts to add insight on the potential of this method for assessing phosphate desorption kinetics from acidic soil, relevant for agronomic and environmental advising of phosphate fertilizer application and use.