Comparative studies for natural and synthetic composites based on molybdate for gadolinium ions separation

The comparison between natural and synthetic composites based on molybdate for the sorption and separation of Gd(III) from Eu(III) and Y(III) was studied. Calcium magnesium molybdate (CaMgMo) and dolomite molybdate (dolomite-Mo) composites have been prepared using the co-precipitation technique and characterised using different analytical tools such as XRD, ATR, SEM, TGA and DTA. The sorption studies applied on Gd(III), Eu(III) and Y(III) by batch technique include the effect of shaking time and pH on sorption efficiency. The data reveal that CaMgMo has higher sorption efficiency than the dolomite-Mo composite at all times and pH values. The distribution coefficients at different pHs have order: Gd(III)>>Eu(III)>Y(III) on both prepared composites. The saturation capacity of two prepared composites towards studied cations has sequence order; Gd(III) >> Eu(III) > Y(III). Reaction kinetics obeys the pseudo-2(nd)-order model. Binary and tertiary systems data confirm that the CaMgMo composite has high separation factors for Gd(III) at different pHs. The real sample applications prove that CaMgMo and dolomite-Mo are excellent composites for the capture of Gd(III) and Y(III) from high-grade monazite (HGM).