【摘要】 制备了整体式Ni/-γAl2O3和添加稀土等碱性助剂的整体式Ni/-γAl2O3催化剂。研究了温度、烷氧比、空速和助剂等因素对甲烷部分氧化反应性能的影响,并利用XRD和TPR对催化剂进行了表征。结果表明,催化剂活性随着温度的升高而增加;CH4转化率随着烷氧比的增加而降低;当空速为1×105h-1时,整体式催化剂的催化性能最佳。添加碱性助剂Ce,La,Na,Sr均有利于改善催化剂的还原性能,提高催化剂的活性。其中添加稀土Ce,La可使副反应CH4+2 O2→CO2+2H2O完全被抑制,从而使H2选择性达到100%。更多还原

【Abstract】 A series of monolithic Ni/γ-Al₂O₃ catalysts with and without basic promoters（Na,Sr,La,Ce） were prepared.The partial oxidation of methane（POM） to syngas was carried out in a continuous-flow and fixed-bed reactor.The influence of reaction conditions（temperature,CH₄/O₂ ration,space velocity） on the performance of catalyst was investigated.The results demonstrate that at high space velocity of 1×10⁵ h^-1,optimal CH₄ conversion can be obtained.Effects of promoters such as Na,Sr,Ce,La were also investigated,and the catalyst samples were characterized by means of temperature-programmed reduction（TPR） and XRD techniques.XRD suggests that the addition of promoters has no influence on the crystal structure of Ni/γ-Al₂O₃ catalyst.The results show that the addition of small amount of promoters improves the reducibility and activity of the catalyst.The side reaction CH₄ + 2 O₂ → CO₂+2H₂O,has been fully restrained and 100% H₂ selectivity has been achieved when Ce,La are promoted respectively.更多还原