摘要
采用浸渍沉淀法制备钙改性NiO/ZnO-Al_2O_3-SiO_2粉末吸附剂,通过压片成型方式制备成型吸附剂。比表面积及孔径分布(BET)、扫描电子显微镜(SEM)和X射线衍射(XRD)表征结果表明,成型吸附剂ZnO和NiO晶体分布均匀,比表面积147.51 m^2/g,孔容0.28 cm^3/g,平均孔径6.38 nm。在420℃、氢气压力2.9 MPa、氢油体积比52.5、质量空速9.76 h^(-1)的反应条件下,成型吸附剂的穿透硫容可达46.51 mg/g,经过5个周期循环再生后脱硫性能保持优良。此外,吸附剂还具有一定的脱氮性能。反应后吸附剂的X射线能量色散谱(EDS)表征结果表明氧质量分数降低,硫质量分数增加;ZnO的XRD特征峰变弱,出现了明显的ZnS特征峰;X射线光电子能谱(XPS)结果表明吸附剂在结合能为852.78 eV处分裂出一个对应于NiS_x的特征谱,说明吸附脱硫过程有NiS_x的生成。
A calcium modified NiO/ZnO-Al2O3-SiO2 powder adsorbent was prepared by impregnation- precipitation method and shaped by tablet-pressed method. B E T,SEM and XRD characterization results show that the shaped adsorbent has a surface area of 147. 51 m^2/g,pore volume of 0. 28 cm^3/g and average pore diameter of 6. 38 nm. The crystals of ZnO and NiO were distributed evenly on the shaped adsorbent. Under the conditions of temperature of 420℃ ,hydrogen pressure of 2. 9 MPa,hydrogen to gasoline volume ratio of 52. 5 and WHSV of 9. 76 h^-1 , the shaped adsorbent has a breakthrough sulfur capacity of 46. 51 mg/g. Its desulfurization performance was maintained quite well after being regenerated for 5 cycles. It also had a certain denitrification performance. EDS characterization results of the used adsorbents showed a decrease in oxygen content and an increase in sulfur content. The intensity of the characteristic peaks of ZnO in XRD spectrum was weakened, while that of ZnS characteristic peaks increased obviously. A peak was split out on XPS at the binding energy of 852. 78 eV,which is the characteristic peak of NiSx. It means that NiSz was formed in the reactive adsorption desulfurization process.
出处
《华东理工大学学报(自然科学版)》
CAS
CSCD
北大核心
2016年第5期630-638,共9页
Journal of East China University of Science and Technology
关键词
吸附剂
压片成型法
汽油
脱硫
脱氮
adsorbent
tablet-pressed method
gasoline
desulfurization
denitrification