膜蒸馏去除水中砷的研究
Study of arsenic removal by membrane distillation
-
摘要: 采用新型膜蒸馏技术对水中As（III）与As（Ⅴ）的去除展开了研究。实验结果表明，膜蒸馏对水中As (III)及As (Ⅴ)具有较高的去除能力：当产水中砷含量超过10 μg/L时，原水中As (III)与As (Ⅴ)的浓度可分别高达40 mg/L和2 000 mg/L。局部润湿现象的存在导致As (III)及As (Ⅴ)跨膜至产水侧，PVDF微孔膜在溶液中的负电性以及As (III)与 As (Ⅴ)在溶液中存在形式的不同导致膜蒸馏对两者去除能力的差异。360 h连续运行过程中产水通量及电导率稳定，且整个过程中As (III)均低于检测限，说明PVDF微孔膜具有良好的疏水性和稳定的除砷性能。Abstract: Arsenite (As (III)) and arsenate (As (V)) removal by membrane distillation (MD) were investigated in the present work. The experimental results indicated that the permeate As (III) and As (V) were under the maximum contaminant limit (10 μg/L) until the feed As (III) and As (V) achieved 40 mg/L and 2 000 mg/L, respectively. Partial wetting phenomenon was the main reason for the permeate arsenic. The PVDF membrane is negative in the solution, thus, compared with As (V), As (III) is more difficult to be removed from water due to the lack of electrostatic exclusion. A 360 h MD performance showed that the PVDF membrane had a stable arsenic removal efficiency,and the permeate As (III) was under the detection limit during the whole process.
-
Key words:
- membrane distillation /
- arsenic /
- groundwater
-
-
点击查看大图
计量
- 文章访问数: 2276
- HTML全文浏览数: 1067
- PDF下载数: 1132
- 施引文献: 0
下载:
