Cobalt (Co)-based catalysts can efficiently reduce the heat waste from sulfate concentration by enhancing sulfite oxidation during wet flue gas desulfurization system. However, arsenic (As) can poison such catalysts and migrate into the sulfate by-products, resulting in severe secondary pollution. In this study, a zero-valent Co/iron (Fe)-based nanoparticle (NZV-Co₂Fe₁) was fabricated and applied as a bifunctional catalyst/adsorbent. The catalytic stability of the Co-based catalyst was enhanced by the introduction of Fe because the poisonous effect of As was substantially suppressed because of the high adsorption capacity of Fe for As. Compared with the noncatalytic benchmark, the presence of 0.5 g/L NZV-Co₂Fe₁ can increase the rate of MgSO₃ oxidation by approximately 12-fold even at a high concentration of As (2.5 mg/L). The Langmuir model was fitted to the As adsorption isotherms, indicating that As uptake is a single-layer adsorption process. The pseudo-second-order kinetic model indicated that As was removed through chemisorption. The oxidation pathway of As(III) involves reactive radicals (mainly OH, SO₄⁻ and SO₅⁻) and ligand-to-metal charge transfer between SO₃²⁻ and Co²⁺. The availability of MgSO₃ improved the removal efficiency at high concentrations of As(III) (1 mg/L). These results indicate that using NZV-Co₂Fe₁ as a catalyst to purify the by-products of flue gas desulfurization can effectively prevent secondary pollution.

钴（Co）基催化剂可通过增强湿法烟气脱硫系统中亚硫酸盐的氧化作用，有效减少硫酸盐浓度产生的热量浪费。然而，砷（As）会毒害这些催化剂并迁移到硫酸盐副产物中，造成严重的二次污染。在这项研究中，制造了一种零价钴/铁（Fe）基纳米颗粒（NZV-Co ₂ Fe ₁）并将其用作双功能催化剂/吸附剂。由于 Fe 对 As 的高吸附能力，基本上抑制了 As 的毒性作用，因此引入 Fe 增强了 Co 基催化剂的催化稳定性。与非催化基准相比，存在 0.5 g/L NZV-Co ₂ Fe ₁即使在高浓度的 As (2.5 mg/L)下，MgSO ₃的氧化速率也可以提高约 12 倍。Langmuir 模型拟合 As 吸附等温线，表明 As 吸收是一个单层吸附过程。准二级动力学模型表明，通过化学吸附去除了 As。As(III) 的氧化途径涉及活性自由基（主要是 OH 、SO ₄ ^-和 SO ₅ ^{- ）以及 SO} ₃ ^2-和 Co ²⁺之间的配体-金属电荷转移。MgSO ₃的可用性提高了在高浓度 As(III) (1 mg/L) 下的去除效率。这些结果表明，使用 NZV-Co ₂Fe ₁作为催化剂净化烟气脱硫副产物可有效防止二次污染。