Removal of trace concentrations of selenium, mostly present as selenate or SeO₄^2–, from contaminated water and wastewater or SO₄^2– presents a formidable challenge that remains unsolved. A new hybrid bio-nano-ix process presented here provides a synergy where selenate (SeO₄^2–) is first biologically reduced first to selenite (HSeO₃^–) under a relatively mild anoxic condition without producing H₂S. Selenite, thus produced, is a relatively strong ligand and has a much higher sorption affinity for hybrid anion exchangers (HAIX-NanoFe) than competing sulfate anions. Extensive laboratory studies provided convincing evidence that the two-step bio-nano-ix process—a fixed-film biological unit followed by a HAIX-NanoFe sorption column—may very selectively remove Se(VI) or SeO₄^2– in the presence of competing sulfate. HAIX-NanoFe is also amenable to efficient regeneration and reuses without any loss of selenite sorption capacity for multiple cycles. The sorbed selenium could thus be concentrated and recovered, thus posing no environmental threat of future contamination.

中文翻译：

---

使用新型 Bio-Nano-IX 工艺从存在竞争硫酸盐 (SO42–) 的受污染水中去除 SeO42– 或 Se(VI)

去除硒的痕量浓度，大多存在硒酸盐或SEO的₄ ^2-，从污染的水和废水或SO ₄ ^2-呈现了仍未解决一个艰巨的挑战。这里介绍的一种新的混合 bio-nano-ix 工艺提供了一种协同作用，其中硒酸盐 (SeO ₄ ^2– ) 在相对温和的缺氧条件下首先被生物还原为亚硒酸盐 (HSeO ₃ ^– )，而不产生 H ₂由此产生的亚硒酸盐是一种相对强的配体，并且对混合阴离子交换剂 (HAIX-NanoFe) 的吸附亲和性比竞争性硫酸根阴离子高得多。广泛的实验室研究提供了令人信服的证据表明，两步生物纳米-IX工艺固定膜生物单元后跟一个HAIX-NanoFe吸附柱可以非常选择性地去除硒（VI）或SEO ₄ ^2-中的存在竞争硫酸盐。HAIX-NanoFe 还可以进行有效的再生和再利用，而不会在多次循环中损失亚硒酸盐的吸附能力。因此，吸附的硒可以被浓缩和回收，从而不会造成未来污染的环境威胁。