Study on Speciation Chemical Analysis of Rare Earth Elements in Soil Based on Green Environmental Technology

Abstract

The impact of rare earth elements on the soil environment is not only related to its total amount, but also more closely related to its chemical form. The green and environmentally friendly acid digestion and morphological continuous extraction methods were used to extract and analyze the total amount of rare earth elements and the forms of rare earth elements in the soil samples. Inductively coupled plasma mass spectrometry was used to determine the content of rare earth elements and the content of rare earth elements in the soil samples. Form content. The results show that the content of rare earth elements in the collected soil samples is 200-1418mg/kg, and the content of light rare earth elements is much higher than that of heavy rare earth elements; the recovery rate of the sum of the combined forms of rare earth elements relative to the total amount is 88.2% to 110%, indicating that the continuous extraction method is suitable for the analysis of rare earth elements in soil samples. The rare earth elements in soil samples mainly exist in the residue state, which is 33%-80%; the co-precipitation state of crystalline iron and manganese hydroxide is 10%-31%; the adsorption state of humus and amorphous oxide is 5.0%-18%; The exchange state and the carbonate combined state are 4.0% to 23%; the amorphous iron-manganese oxide co-precipitation state is less than 3%. The influence of the location of the sampling point and the nature of rare earth elements on the content of rare earth elements was analysed, and the influence of soil properties on the distribution of morphology was discussed.