| K+对Fe(Ⅵ)生成的稳定促进作用和机理研究 |
| 摘要点击 2810 全文点击 1559 投稿时间：2007-05-24 修订日期：2007-09-14 |
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| 中文关键词 Fe(Ⅵ) 高铁酸盐 K+ 氧化剂 |
| 英文关键词 Fe(Ⅵ) ferrate potassium ion oxidant |
| DOI 10.13227/j.hjkx.20080323 |
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| 中文摘要 |
| 研究了在生成高铁酸盐反应过程中K+对Fe(Ⅵ)的稳定促进作用和机理.结果表明，当反应温度大于50℃时，K+比Na+更有利于高铁酸盐的生成.K+促进高铁酸盐溶液生成的最佳反应温度为65℃.在生成高铁酸盐反应过程中，增加K+浓度能提高高铁酸盐的产率，并且随着硝酸铁投加量的增加，K+影响显著.在硝酸铁投加量为85 g/L时，采用4.4 mol/L KOH制备的Fe(Ⅵ)浓度为0.05 mol/L；加入2 mol/L K+后，Fe(Ⅵ)浓度增加到0.15 mol/L.K+对高铁酸盐溶液生成浓度的影响在硝酸铁投加量大于75 g/L，反应温度低于55℃，ClO-浓度低于1.16 mol/L时较为显著.K+在一定程度上可替代部分碱度，降低OH-用量.在反应过程中K+能包裹在FeO2-4周围，减少Fe3+与FeO2-4接触，从而减缓Fe3+对FeO2-4的催化分解作用；同时K+能与FeO2-4生成K2FeO4晶体沉淀析出，降低溶液中FeO2-4浓度，Fe(Ⅵ)分解速率减缓，稳定性增加，Fe(Ⅵ)生成浓度增加. |
| 英文摘要 |
| The mechanism and promotion effects of K+ on the yield of Fe(Ⅵ) were studied during the reaction of forming ferrate. The experiment results showed that K+ is far better than Na+ for the preparation of Fe(Ⅵ) at temperatures higher than 50℃. The optimal temperature for the preparation of Fe(Ⅵ) with K+ is 65℃. During the reaction, the yield of ferrate increases with the concentration of K+, and the promotion effect of K+ is obviously with ferric nitrate dosage increase. The Fe(Ⅵ) concentration prepared with 4.4 mol/L KOH is 0.05 mol/L at 85 g/L ferric nitrate; and which achieves 0.15 mol/L when added 2 mol/L K+ . The promotion effect of K+ on the yield of ferrate is remarkable when ferric nitrate dosage is higher than 75 g/L, reaction temperature is below 55℃ and ClO- concentration is lower than 1.16 mol/L. The K+ can substitute for partly alkalinity and reduce the concentration of OH- in the reaction solution. During the reaction, the K+ can enwrap around FeO2-4 that can reduce the contact between Fe3+ and FeO2-4, and decrease the catalysis effect of Fe3+ on FeO2-4. At the same time, K+ can react with FeO2-4 to form solid K2FeO4, which will lower the Fe(Ⅵ) concentration, decrease the decomposition rate of Fe(Ⅵ), enhance the stability and improve the yield of Fe(Ⅵ). |
