To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liqu...To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liquid separation for copper slag slurry,the liquid-phase part has a critical influence on removing NO_(x)and SO_(2).Also,the leached metal ions played a crucial role in the absorption of SO_(2)and NO_(x).Subsequently,the effects of single/multi-metal ions on NO_(x)removal was investigated.The results showed that the leached metal from copper converter slag(Al^(3+),Cu^((2+),and Mg^((2+))and KMnO_(4)had a synergistic effect on NO_(x)removal,thereby improving the NO_(x)removal efficiency.Whereas Fe^(2+) had an inhibitory effect on the NO_(x)removal owing to the reaction between Fe^(2+) and KMnO_(4),thereby consuming the KMnO_(4).Besides,SO_(2)was converted to SO_(4)^(2-) completely partly due to the liquid catalytic oxidation by metal ions.The XRD and XPS results indicated that the Fe(Ⅱ)species(Fe_(2)SiO_(4),Fe_(3)O_(4))in copper slag can react with H+ions with the generation of Fe^(2+),and further consumed the KMnO_(4),thereby resulting in a decrease in the NO_(x)removal.The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms.The role of copper slag is as follows:(1)the alkaline substances in copper slag can absorb SO_(2)and NO_(2)by KMnO_(4)oxidation.(2)copper slag may function as a catalyst to accelerate SO_(2)conversion and improve NO_(x)removal by synergistic effect between leached metal ions and KMnO_(4).展开更多
基金supported by the National Natural Science Foundation of China(Nos.51708266,51968034,21667015,and 41807373)the National Key Research and Development Program of China(Nos.2018YFC0213400 and 2018YFC1900305)。
文摘To achieve"waste controlled by waste",a novel wet process using KMnO_(4)/copper converter slag slurry for simultaneously removing SO_(2)and NO_(x)from acid-making tail gas was proposed.Through the solid-liquid separation for copper slag slurry,the liquid-phase part has a critical influence on removing NO_(x)and SO_(2).Also,the leached metal ions played a crucial role in the absorption of SO_(2)and NO_(x).Subsequently,the effects of single/multi-metal ions on NO_(x)removal was investigated.The results showed that the leached metal from copper converter slag(Al^(3+),Cu^((2+),and Mg^((2+))and KMnO_(4)had a synergistic effect on NO_(x)removal,thereby improving the NO_(x)removal efficiency.Whereas Fe^(2+) had an inhibitory effect on the NO_(x)removal owing to the reaction between Fe^(2+) and KMnO_(4),thereby consuming the KMnO_(4).Besides,SO_(2)was converted to SO_(4)^(2-) completely partly due to the liquid catalytic oxidation by metal ions.The XRD and XPS results indicated that the Fe(Ⅱ)species(Fe_(2)SiO_(4),Fe_(3)O_(4))in copper slag can react with H+ions with the generation of Fe^(2+),and further consumed the KMnO_(4),thereby resulting in a decrease in the NO_(x)removal.The characterization of the slags and solutions before and after reaction led us to propose the possible mechanisms.The role of copper slag is as follows:(1)the alkaline substances in copper slag can absorb SO_(2)and NO_(2)by KMnO_(4)oxidation.(2)copper slag may function as a catalyst to accelerate SO_(2)conversion and improve NO_(x)removal by synergistic effect between leached metal ions and KMnO_(4).