无机盐和有机物对纳滤膜除砷效率的研究

Study of Inorganic Matter and Organic Matter Affecting Pentavalent Arsenic Removal by Nanofiltration

采用纳滤膜(NF90,NF270,HL)低压错流过滤含砷水,研究一价、二价无机离子和溶解性天然有机物(dissolved organic matter,DOM)对纳滤膜去除水中五价砷(As(Ⅴ))的影响.研究结果表明,原水中无机盐使纳滤膜通量下降,且无机盐浓度增加,通量下降量增大.无机离子的存在导致纳滤膜除砷效率降低,但随着无机离子浓度的增加,砷的去除效率呈现出升高的趋势.天然有机物对纳滤膜除砷效率也有很大的影响,有机物能与砷缔合,且有机物在膜表面形成的凝聚层直接影响纳滤膜对砷的去除效果.

The paper discusses the removal of pentavalent arsenic （As （V）） from synthetic water by low-pressure nanofihration （NF90, NF270, HL） membranes. The effects of monovalent ions, divalent ions and natural organic matter（dissolved organic matter, DOM） was investigated. The results show that the water flux was declined by the inorganic ions. The removal rate of arsenic also decreased because of the presence of inorganic matter. And, the rejection of arsenic （V） increases with the increasing of the concentration of inorganic ions. The reaction between dissolved organic matter （DOM） and arsenic, and the layer of compounds that adsorbed to or connected to near the membrane surface also affect the removal rate significantly.