研究报告
于生慧,王艳,王翼远,郭军康,张蕾.乙基黄药对施氏矿物吸附Cr(Ⅵ)的影响研究[J].环境科学学报,2022,42(12):61-69
乙基黄药对施氏矿物吸附Cr(Ⅵ)的影响研究
- Effect of ethyl xanthate on Cr(Ⅵ) adsorption by schwertmannite mineral
- 基金项目:国家自然科学基金(No. 41702038);陕西省自然科学基金(No. 2019JM-375);陕西省科技创新团队项目(No.2022TD-09);陕西省重点产业链项目(No.2022ZDLNY02-02)
- 于生慧
- 陕西科技大学环境科学与工程学院,西安 710021
- 王艳
- 陕西科技大学环境科学与工程学院,西安 710021
- 王翼远
- 陕西科技大学环境科学与工程学院,西安 710021
- 郭军康
- 陕西科技大学环境科学与工程学院,西安 710021
- 张蕾
- 陕西科技大学环境科学与工程学院,西安 710021
- 摘要:选矿药剂在矿产资源开发中被大量使用,环境中残留的选矿药剂及其衍生物对重金属的迁移、转化等环境行为产生重要影响.施氏矿物是广泛存在于酸性矿山废水中的一种典型的羟基硫酸盐铁矿物,对重金属具有明显的吸附作用.然而,浮选药剂对施氏矿物富集重金属的影响有待深入研究.本研究采用快速化学法合成施氏矿物,通过批量吸附实验法系统探究典型浮选药剂乙基黄药存在条件下,反应体系pH、接触时间、浮选药剂浓度、Cr(VI)初始浓度等因素对施氏矿物吸附Cr(VI)的影响规律.结果表明:在酸性条件下,乙基黄原酸钠抑制施氏矿物对Cr(Ⅵ)的吸附作用;在碱性条件下,乙基黄原酸钠对施氏矿物吸附Cr(Ⅵ)具有明显的促进作用.在初始pH条件为8.5时,施氏矿物对Cr(VI)的最大去除容量达到56.96 mg?g-1,与最佳条件下施氏矿物对Cr(VI)的吸附容量 (40.4 mg?g-1) 相比,吸附容量提升了41%.乙基黄原酸钠存在条件下施氏矿物对Cr(Ⅵ)的吸附符合准二级动力学,表明该吸附过程以化学吸附机制为主.在Cr(VI)的吸附过程中,黄原酸基将Cr(Ⅵ)还原为Cr(Ⅲ),从而增强了了施氏矿物在碱性条件下对Cr(VI)的去除能力.研究结果表明乙基黄药的存在能够显著影响施氏矿物对Cr(VI)的吸附过程及吸附机制.
- Abstract:Ore dressing chemicals are widely used in the exploitation of mineral resources, the residual chemicals and their derivatives have important impacts on the migration and transformation of heavy metal ions. Schwertmannite (Sch), a typical hydroxysulfate iron mineral occurred in acid mine wastewater, is an important adsorbent for enriching heavy metal ions. To date, the effects of flotation reagents on the adsorption of heavy metal ions by Sch still needs to be further studied. In this study, Sch was first synthesized via a rapid chemical method, and the effects of pH, contact time, the concentration of sodium ethyl xanthate and the initial concentration of Cr(VI) on the adsorption of Cr(VI) by Sch minerals were investigated in the presences of ethyl xanthate. Under the influence of sodium ethyl xanthate, the Cr(VI) sorption efficiency by Sch was inhibited in acidic conditions, whereas sodium ethyl xanthate can significantly promote the adsorption of Cr(Ⅵ) by Sch under alkaline conditions. The sorption capacity of sch to Cr(VI) was 56.96 mg?g-1 at pH of 8.5, about 41% higher than the reported counterparts under acidic condition (40.4 mg?g-1). The sorption of Cr(VI) ions by sch mediated by sodium ethyl xanthate could be well explained by the pseudo-second-order kinetic model, indicating that the Cr(VI) removal process was controlled by a chemical reaction at the solid/solution interface. Moreover, Cr(VI) was reduced to Cr(III) by the xanthate group under alkaline conditions, leading to the enhance removal capacity to Cr(VI). The results indicated that the Cr(VI) sorption processes and mechanism of Sch was changed greatly under the influence of sodium ethyl xanthate.