No abstract

Phosphate oxygen isotope analysis is an effective tool for investigating phosphorus migration and transformation in water bodies. However, existing pretreatment methods for this technology are severely restricted by large sample requirements, cumbersome operation, and poor applicability. To optimize the pretreatment method, hydrated zirconia was prepared by liquid-phase precipitation. Zeolite, D001 macroporous resin, activated carbon, and ceramsite were selected as potential support materials. The optimum zirconium support material was selected after field enrichment and laboratory elution experiments. The optimum in situ enrichment time, material dose, and elution time were determined using response surface methodology. The D001 resin provided the best selective adsorption and elution capacity for phosphate. The optimum parameters for an in situ phosphate-enrichment blanket were obtained by response surface optimization as a zirconium-loaded D001 resin mass of 13 g, enrichment time of 360 min, and elution time of 853 min. After purification, a bright yellow Ag3PO4 solid was obtained. The results showed that the optimization method was reliable. These results provide a foundation for the application of phosphate oxygen isotope analysis in freshwater bodies.

No abstract

Phosphate oxygen isotope analysis is an effective tool for investigating phosphorus migration and transformation in water bodies. Unfortunately, current pretreatment methods for this technology are significantly limited due to their demanding sample amount requirements, complex operation, and limited scope of application. In order to enhance the efficiency of the pretreatment process, hydrated zirconia was synthesized through liquid-phase precipitation. Zeolite, D001 macroporous resin, activated carbon, and ceramsite were chosen as possible candidate materials for loading purposes. The optimal zirconium loading material was identified through a combination of field enrichment and laboratory elution experiments. The ideal in situ enrichment duration, material dosages, and elution time were ascertained using response surface methodology. The findings showed that D001 resin exhibited superior selective adsorption and elution capacity for phosphate. The response surface optimization yielded the optimal parameters for the in situ phosphate-enrichment blanket: a mass of 13 g for zirconium-loaded D001 resin, an enrichment period of 360 min, and an elution period of 853 min. The attainment of a bright yellow Ag3PO4 solid after purification served as proof of the reliability of the optimization method. The obtained results provide a fundamental basis for the preparation and application of phosphate oxygen isotope analysis in freshwater ecosystem.