Reduction of Fe(II)EDTA-NO with palladium based catalysts
REN Xiaocong1， HU Zirui2， ZHANG Guangxu2
(1.Department of Biological and Chemical Engineering， Zhixing College of HuBei University， Wuhan 430070， China； 2.School of Chemistry， Chemical Engineering and Life Sciences， Wuhan University of Technology， Wuhan 430070， China)
摘要Fe(Ⅱ)EDTA络合脱硝法对一氧化氮(NO)具有良好的吸收效果，是脱硝技术重点研究方向，但Fe(Ⅱ)EDTA-NO络合液再生困难限制了它的发展.为达到Fe(II)EDTA络合液循环使用的目的，以阴离子交换树脂IRA900为载体，通过浸渍法负载钯前驱体，经硼氢化钠还原后制备出了Pd/IRA900催化剂.通过X射线衍射、X射线光电子能谱图、透射电子显微镜、热重分析等表征表明，Pd/IRA900催化剂中钯纳米微团的平均粒径为2.14 nm，Pd0含量为84%(质量分数)，对还原Fe(II)EDTA-NO有着良好的催化活性.搭建一套可持续运转的流化床试验装置，评价结果如下：在气相的条件为总流量200 L ·h－1、NO含量为0.07%(体积分数)、含氧量10%，络合液再生条件为初始浓度0.05 mol ·L－1、温度60 ℃、pH＝5、液气比6的最佳工艺条件下，可以维持脱硝率90%以上稳定运行300 min.
Abstract：Fe(II)EDTA complexation denitrification method has a good absorption effect on nitric oxide (NO) and is an important research direction in denitrification technology. However， the difficulty in regenerating Fe(II)EDTA-NO complexation solution limits its development. To achieve the goal of recycling Fe(II)EDTA complex solution， Pd/IRA900 catalyst was prepared using anion exchange resin IRA900 as a carrier， and palladium precursor was loaded by impregnation method， followed by reduction with sodium borohydride. X-ray diffraction， X-ray photoelectron spectroscopy， transmission electron microscopy and thermogravimetric analysis showed that the average particle size of palladium nanoclusters in Pd/IRA900 catalyst was 2.14 nm with the Pd0 content of 84% (mass fraction) and the Pd/IRA900 catalyst exhibited good catalytic activity for reducing Fe (II) EDTA-NO. A sustainable fluidized bed testing device was builded， and the evaluation results were as follows： under the optimal process conditions of total gas flow rate of 200 L·h－1， NO concentration of 0.07% (volume fraction)， oxygen content of 10%， initial complex solution concentration of 0.05 mol/L， temperature of 60 ℃， pH＝5 and liquid gas ratio of 6， the denitrification rate could be maintained above 90% for stable operation over 300 min.
2025, Vol. 59 
