State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, Sichuan, China.
Chongqing Academy of Metrology and Quality Inspection, Chongqing, 401121, China.
Environ Sci Pollut Res Int. 2023 Mar;30(12):34069-34084. doi: 10.1007/s11356-022-24621-1. Epub 2022 Dec 12.
The geochemical cycling of vanadium (V) in mining areas has attracted much attention. However, little knowledge was about the effects of tailing colloids on the fate and transport of vanadium in tailing reservoirs which was ignored before. This study investigated the interactions of tailing colloids from vanadium-titanium magnetite with vanadium. Colloid characterization, tailing leaching, adsorption, and column experiments of single and cotransport of tailing colloid with V were conducted. Results show that 98.08% V in the vanadium-titanium magnetite tailing was in the residual state with limited leachable V under various conditions. The adsorption of V to the tailing colloid was via electrostatic attraction and surface complexation on the heterogeneously distributed sorption sites on the colloid surface. The adsorption control step was the diffusion of V into the tailing colloid pores. The increase in pH and the decrease in ionic strength (IS) promoted the single transport of tailing colloid and V in quartz sand columns. In cotransport scenarios, V promoted the transport of tailing colloids via the surface coating effect. In contrast, the transport of V was retarded by the adsorbed tailing colloid on the quartz sand surface. The pre-adsorbed V in the column enhanced the subsequent transport of tailing colloids by electrical repulsion, while the pre-adsorbed tailing colloids facilitated the subsequent transport of V via cotransport of the released colloids with V. The high mobility of the tailing colloid and V and their cotransport in the porous media highly demonstrated the potential V pollution pathways that need to be taken into account.
矿区钒（V）的地球化学循环引起了广泛关注。然而，以前人们忽略了尾矿胶体对尾矿库中钒的赋存和迁移的影响。本研究调查了来自钛磁铁矿尾矿的胶体与钒的相互作用。进行了胶体特性、尾矿浸出、吸附以及单一流体和胶体与 V 的共运移柱实验。结果表明，在各种条件下，钛磁铁矿尾矿中的 98.08%V 处于残余状态，可浸出 V 有限。V 对尾矿胶体的吸附是通过静电吸引和胶体表面不均匀分布的吸附位上的表面络合作用实现的。吸附控制步骤是 V 向尾矿胶体孔隙中的扩散。pH 值的增加和离子强度（IS）的降低促进了石英砂柱中单一流体和 V 的运移。在共运移情景下，V 通过表面覆盖效应促进了尾矿胶体的运移。相比之下，吸附在石英砂表面上的尾矿胶体则会阻碍 V 的运移。柱中预先吸附的 V 通过电排斥作用增强了随后尾矿胶体的运移，而预先吸附的尾矿胶体则通过释放的带有 V 的胶体共运移促进了随后 V 的运移。尾矿胶体和 V 的高迁移性及其在多孔介质中的共运移高度表明了需要考虑的潜在 V 污染途径。
