Buffer effect of MgO on Na2SO3 to stabilize S(IV) for the enhancement in simultaneous absorption of NOx and SO2 from non-ferrous smelting gas
Buffer effect of MgO on Na2SO3 to stabilize S(IV) for the enhancement in simultaneous absorption of NOx and SO2 from non-ferrous smelting gas
复制标题
DOI：
10.1007/s11356-022-20748-3
复制
发表时间：
2022-05
影响因子：
5.8
通讯作者：
Wenjun Huang;Sichao Li;Hong Wang;P. Cui;Haomiao Xu;Can Cheng;Zan Qu;N. Yan
中科院分区：
文献类型：
--
作者：
Wenjun Huang;Sichao Li;Hong Wang;P. Cui;Haomiao Xu;Can Cheng;Zan Qu;N. Yan
亚硫酸盐氧化-还原-吸附是一种很有前途的同时脱除nox和SO2的工艺。然而，亚硫酸盐的过度氧化和nox与so2的竞争吸收限制了它的应用。为了解决这些问题，提高吸收率，提出了抗氧剂与碱性剂的匹配策略。两种抑制剂的对比结果表明，对苯二酚对S(IV) （SO32-/HSO3-）氧化具有长期高效的抑制作用。碱性药剂的比较表明，MgO和对苯二酚的非均相混合na2so3溶液的吸收性能优于其他组合。0.15 mol/L Na2SO350 mL溶液中添加0.1%对苯二酚（HQ）和0.09 mol/L MgO时，NOxin的吸收量为2.24 mmol，比未添加添加剂时提高了5倍。此外，对pH影响的研究表明，MgO混合物的pH可以长时间稳定在9-10，而na2co3混合物的pH下降更快。进一步的研究表明，MgO的水化作用使MgO的溶液保持较高的ph值，这也是MgO与对苯二酚组合在脱硫脱硝性能上优于na2co3与对苯二酚组合的主要原因。
Oxidation–reduction-absorption based on sulfite is a promising process for simultaneous removal of NOxand SO2. However, excessive oxidation of sulfite and competitive absorption between NOxand SO2limit its application. A matching strategy between antioxidants and alkaline agents has been proposed to solve these problems and enhance the absorption process. The comparison results of inhibitors showed that hydroquinone exhibited long-term high-efficiency inhibition of S(IV) (SO32-/HSO3-) oxidation. The comparison of alkaline agents showed that the Na2SO3solution with heterogeneous mixture of MgO and hydroquinone exhibited better absorption performance than that with other combinations. The absorption amounts of NOxin 0.15 mol/L Na2SO350 mL solution added 0.1% hydroquinone (HQ) with 0.09 mol/L MgO were 2.24 mmol, which improved 5 times than that without additives. In addition, studies on the influence of pH showed that the pH of MgO mixture could be stabilized at 9–10 for a long time, while the pH of Na2CO3mixture decreased faster. Further studies suggested that the hydration of MgO resulted in the solution with MgO keeping high pH. This is also the main reason why the combination of MgO and hydroquinone is superior to the combination of Na2CO3and hydroquinone in desulfurization and denitration performance.