摘要
转炉炼钢工艺过程中产生的转炉煤气中含有大量的CO,当CO浓度<35%时,企业无法回收利用,通常通过放散塔直燃排放,造成严重的能源浪费和环境污染.CO催化氧化技术是解决上述问题的有效手段,可同时实现转炉放散煤气余热利用和CO催化消除.本文利用预处理的市售氢氧化铁为载体前体,低担载量的金属Pd为活性组分,采用简单浸渍和原位还原方法制备了系列Pd/FeO_(x)催化剂,用于催化氧化转炉炼钢炼铁过程中产生的CO.催化剂在固定床评价装置中的运行结果表明,模拟放散煤气中CO体积浓度为50%和35%,Pd/FeO_(x)催化剂活性金属担载量为0.1%、0.2%和1%时,CO在室温下均可完全氧化并自持燃烧;当CO浓度为5%时,1%Pd/FeO_(x)催化剂中可在70℃实现完全转化.利用XRD、XPS、TEM、H_(2)-TPR等技术对催化剂进行了系统表征,结果表明载体FeO_(x)与Pd的强相互作用以及还原过程中产生的大量氧空位,可能是Pd/FeO_(x)催化性能优异的原因.此外,1%Pd/FeO_(x)可稳定运行900h以上,展现出良好的催化稳定性和潜在的工业应用前景.
The converter gas produced in the process of converter steelmaking contains a large amount of CO,when the CO concentration<35% cannot meet the recovery standard,it is usually discharged by direct combustion through the discharging tower,which will cause a serious waste of energy and environmental pollution.The catalytic oxidation technology is an effective technology to realize the utilization of converter discharged gas residual heat and the efficient conversion of CO at low temperature.In this study,a series of Pd/FeO_(x) catalysts were prepared via simple impregnation following in situ reduction method using treated commercially available iron hydroxide as the carrier precursor and low-loading Pd as the active component for the catalytic oxidation of CO produced in the process of converter steelmaking and iron-making.The catalytic performance of the catalysts was evaluated in a fixed-bed reactor,and the results displayed that the three Pd/FeO_(x) catalysts with the active metal loadings of 0.1%,0.2%,and 1%were able to completely eliminate CO and selfsustained combustion at room temperature in simulated converter off-gas as CO volume concentrations was 50% and 35%,and the 1%Pd/FeO_(x) catalyst was able to completely eliminate CO at 70℃ in the presence of a low concentration of CO(5%).In addition,the catalysts were characterized by XRD,XPS,TEM,and H_(2)-TPR,the characterization results showed that the strong interaction between the Pd species and the support,and a large number of oxygen vacancies formed during the reduction process might be the main reason for the excellent catalytic performance of the Pd/FeO_(x) catalysts.Meanwhile,the catalyst stability was also explored.The catalyst 1%Pd/FeO_(x) can be used more than 900 h on the self-sustained combustion,showing good catalytic activity and potential industrial application prospects.
作者
魏国立
张伟
黄永吉
刘士民
崔新江
石峰
WEI Guoli;ZHANG Wei;HUANG Yongji;LIU Shimin;CUI Xinjiang;SHI Feng(Jiuquan Iron and Steel(Group)Co.,Ltd.,Jiayuguan,Gansu 735100,China;State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences,Lanzhou,Gansu 730000,China)
出处
《分子催化(中英文)》
北大核心
2025年第5期446-454,I0003,I0004,共11页
Journal of Molecular Catalysis(China)
基金
甘肃省重点科技项目(22ZD6GB019).
关键词
转炉放散煤气
一氧化碳
催化氧化
自持燃烧
催化性能
converter off-gas
carbon monoxide
catalytic oxidation
self-sustained combustion
catalytic stability
