摘要
为了研究碱金属钾、钠对焦炭劣化作用的区别,首先将焦炭置于不同含量的钾、钠气氛下进行吸附实验,然后对吸附碱金属后的焦炭进行扫描电镜观察、能谱及X射线衍射分析和热态性能测试.由于钠更加容易以表面吸附的形式覆盖在焦炭表面,所以在碱蒸气质量比相同的气氛下,钠的吸附量要高于钾.表面吸附的碱金属对焦炭溶损反应有阻碍作用.在相同吸附量情况下,吸附钾后的焦炭中与碳化学结合的钾居多,反应性更高.另外,钾金属本身对焦炭破坏作用就很大,钾原子会插入碳层引起微晶多维膨胀,使焦炭微观组织产生破裂,并且这些新生的裂纹导致吸附钾焦炭与吸附钠焦炭在溶损方式上的不同.
In order to research the differences of degradation effect on coke between potassium and sodium gaseous adsorption experiments on coke in potassium and sodium atmospheres were carried out, and the coke samples were analyzed by scanning electron microscopy （SEM）, energy dispersive spectrometry （EDS）, X-ray diffraction （XRD） and thermal properties test. It is found that sodium more easily covers the surface of coke in surface-absorbed form, so the absorption amount of sodium is greater than that of potassium in the alkali atmospheres with the same mass ratio. Alkali metals absorbed on the surface of micropores have resistant effect on the solution loss reaction of coke. Compared with sodium in sodium-adsorbed coke, in the same absorption amount condition, more potassium in potassium-absorbed coke chemically combines with carbon and thus potassium-absorbed coke has a higher reactivity. In addition, potassium has strong destroying effect on coke. Potassium atoms can intercalate into carbon layers and cause the multidimensional expansion of microcrystals, which leads to breakages in the microstructure of coke. These new cracks result in the different ways of solution loss between potassium-adsorbed coke and sodium-adsorbed coke.
出处
《北京科技大学学报》
EI
CAS
CSCD
北大核心
2013年第4期438-447,共10页
Journal of University of Science and Technology Beijing
基金
国家自然科学基金资助项目(60872147)
中央高校基本科研业务费专项资金资助项目(FRF-TP-12-029A)
关键词
高炉
碱金属
焦炭
劣化
催化作用
blast furnaces
alkali metals
coke
degradation
catalysis
