Removal of Aqueous Uranyl and Arsenate Mixtures by Natural Limestone and Hydroxyapatite Precipitates, Rio Paguate, NM, 2022-2023

This dataset documents a series of laboratory batch experiments investigating the removal of aqueous uranyl (U) and arsenate (As) mixtures using natural limestone and precipitated hydroxyapatite (HAp, Ca₁₀(PO₄)₆(OH)₂) as reactive materials. The main objective of the study was to address the challenge of simultaneous removal of uranyl cations and arsenate oxyanions by using mineral-based adsorbents, such as limestone. The precipitation of HAp enhanced As removal while maintaining high uranium immobilization efficiency.The archived data include measurements of aqueous U and As at trace-level concentrations under varying experimental conditions, including pH (ranging from 7 to 11), initial contaminant concentrations (0.05–1 mM), and the addition of calcium (Ca²⁺) and phosphate (PO₄³⁻) to promote HAp precipitation. Experiments were conducted in triplicate to ensure reproducibility, and solid-phase characterization data (from pXRD, SEM/EDX, and electron microprobe analysis) are also included to support the interpretation of removal mechanisms. A key finding revealed from the data is that near-complete removal of U (>97%) with As removal between 30 and 98% were achieved under pH conditions around 9. This dataset provides a comprehensive record of solution chemistry and treatment performance, serving as a fundamental resource for evaluating the effectiveness of natural mineral-based approaches for remediating co-contaminated waters.本数据集记录了一系列实验室批量实验，探究以天然石灰石与沉淀羟基磷灰石（hydroxyapatite, HAp, Ca₁₀(PO₄)₆(OH)₂）作为反应材料，去除水溶液中铀酰（U）与砷酸盐（As）混合污染物的效果。本研究的核心目标为解决利用矿物基吸附剂（如石灰石）同时去除铀酰阳离子与砷酸含氧阴离子的技术难题。HAp的沉淀作用可强化砷酸盐去除效果，同时维持铀的高固定效率。存档数据涵盖了痕量浓度水溶液中铀与砷的检测结果，实验条件涵盖pH值范围7~11、初始污染物浓度0.05~1 mM，以及为促进HAp沉淀而添加的钙离子（Ca²⁺）与磷酸根（PO₄³⁻）变量。所有实验均设置三次重复以保证可重复性，同时附带固相表征数据（来自粉末X射线衍射（pXRD）、扫描电镜/能谱联用（SEM/EDX）以及电子探针显微分析），用于辅助阐释污染物去除机制。本数据集揭示的核心结论为：在pH约为9的条件下，可实现铀的近乎完全去除（>97%），同时砷酸盐去除率可达30%~98%。本数据集完整记录了溶液化学特性与处理性能，可为评估天然矿物基方法修复复合污染水体的有效性提供基础研究资源。