摘要
采用均匀沉淀法制备纳米ZnO,经260℃,360℃,460℃和550℃焙烧制备的纳米ZnO均具有六方纤锌矿结构,平均粒径分别为14.3nm,21.2nm,24.1nm和35.3nm。通过TEM、TPR、XRD和XPS等技术对脱硫剂进行了表征。结果表明,纳米ZnO提高了对H2S的室温去除率,室温脱除H2S的活性时间是分析纯ZnO的近40倍;其脱硫性能随粒径增大,氧空位减少而下降,脱硫后高结合能的硫物种增多,硫取代晶格氧的趋势增大。说明粒径大小和氧空位是纳米ZnO室温脱硫的主要影响因素。纳米ZnO(14.3nm)可直接将H2S选择氧化为单质硫,尾气中未见SO2产生。
The ZnO nanoparticles were prepared by homogeneous deposition. The ZnO nanoparticles thus prepared after calcination at 260 degrees C, 360 degrees C, 460 degrees C and 550 degrees C were with hexagonal wurtzite structure. The average particle size was 14.3 nm, 21.2 nm, 24.1 nm and 35.3 nm, respectively. The desulfurzation agent was characterized by TEM, TPR, XRD and XPS before and after desulfurization reaction, respectively. It is concluded that the ZnO nanoparticles improve the efficiency of H2S desulfurization at low temperature. The life time for H2S desulfurization at room temperature was about 40 times that of analytical pure ZnO. The performance of ZnO nanoparticles for desulfurization was decreased with the increase in particle size and decrease in oxygen vacancy sulfur species with higher binding energy increased, and the tendency for sulfur to substitute crystal matrix oxygen became significant after desulfurization. It is demonstrated that the size and oxygen vacancy are the main factors influncing the performance of desulfurization at low temperature. ZnO nanoparticles (14.3 nm) could oxidize H2S into elemental sulfur selectively. The product of SO2 was not observed in the end gases.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2005年第8期1149-1154,共6页
Chinese Journal of Inorganic Chemistry
基金
国家自然科学基金资助项目(No.50478026)
水质科学与水环境恢复工程北京市重点实验室开放研究基金资助项目。
关键词
纳米ZNO
室温
脱硫
单质硫
ZnO nanoparticles
room temperature
desulfurization
elemental sulfur
