摘要
采用浸渍法制备了质量分数11.32%Cu/γ-Al2O3催化剂,采用固定床反应器,考察了SO2浓度（0-0.02%）对低浓度甲烷（体积分数,3%）催化燃烧特性的影响,通过反应前后催化剂的微观结构及化学成分检测,结合理论分析,探讨了催化反应的硫中毒原因。研究表明,SO2的通入导致了Cu/γ-Al2O3催化剂活性及稳定性的降低,在同一反应温度下,甲烷转化率随着SO2浓度的增加而下降。SEM、EDS、FT-IR、XRD表征结果表明,SO2会导致Cu/γ-Al2O3催化剂表面出现结块现象,催化剂表面有硫元素的累积,且以硫酸盐的形式存在,其主要成分为硫酸铜（CuSO4）。在富氧条件下,SO2分子及氧离子在Cu^2＋上吸附所形成的硫酸铜,附着在催化剂表面,形成一层坚硬的外壳,是产生硫中毒现象的根本原因。
The Cu/γ-Al2O3catalysts with 11. 32% copper contents prepared by the incipient wetness impregnation were tested in a fixed bed reactor. The effects of SO2 concentration（0 - 0. 02%） on the combustion characteristic and stability of low concentration methane（3%） over Cu/γ-Al2O3catalysts were investigated. By the analysis of microstructure and chemical component of fresh and aged catalysts, the mechanism of sulfur poisoning in the catalytic reaction was discussed by combining with the theoretical analysis. The results show that the addition of SO2in the feed gases leads to a decrease of activity and stability of the catalysts. The methane conversion decreases rapidly with the increasing concentration of SO2. The results of SEM,EDS,FT-IR and XRD reveal that the presence of SO2in the feed gases can result in agglomeration and accumulation of sulfur on the surface of Cu/γ-Al2O3catalysts. Sulfur is in the form of sulfate,which mainly contains copper sulfate（CuSO4）. Under the condition of oxygen enrichment,the copper sulfate produced by the absorption of SO2and oxygen ions on Cu2＋is attached to the surface of catalysts and forms a hard shell,which is the major reason for the sulfur poisoning.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2014年第5期635-640,共6页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金(51206200)
中央高校基本科研业务经费(CDJZR12140031)
