【摘要】 制备系列K改性的β-Mo2C催化剂并对其CO加氢合成低碳混合醇性能进行了考察。结果表明,K改性使β-Mo2C催化剂的CO加氢选择性发生显著变化。β-Mo2C催化剂CO加氢的产物主要为C1~C4烷烃,经K改性后β-Mo2C催化剂上产物主要为C1~C5低碳醇,其中高级醇(C2+OH)选择性可达到33.78%。通过对碱金属质量分数的考察发现,当K/Mo(原子比)为0.2时,总醇选择性达到最大值,低碳醇的时空收率达到0.12 g/(mL.h-1)。β-Mo2C催化剂上醇烃产物均符合线性An-derson-Schu ltz-F lory(A-S-F)分布曲线,而K改性β-Mo2C催化剂上醇产物为独特的甲醇负偏离A-S-F分布。可见,K助剂的加入有效促进了低碳醇的形成,尤其是促进了C1OH到C2OH的链增长步骤。更多还原

【Abstract】 The modification effects of K₂CO₃ on β-Mo₂C catalysts for mixed alcohols synthesis from CO hydrogenation were studied.Un-prompted β-Mo₂C produced mainly hydrocarbons of C₁-C₄ under the reaction conditions of 573K,8.0MPa,H₂/CO=1.0,GHSV=2000h^-1.Addition of K₂CO₃ to β-Mo₂C resulted in remarkable selectivity shift from hydrocarbons to alcohols.Moreover,the promoter of potassium enhanced the ability of chain propagation of β-Mo₂C with the higher selectivity of C₂₊ alcohols.The investigations of the loadings of K₂CO₃ in β-Mo₂C revealed that the maximum of alcohol yield obtained at K/Mo（molar ratio） =0.2.On K/β-Mo₂C catalysts,the distribution of hydrocarbons obeyed the traditional linear Anderson-Schultz-Flory equation,while the distribution of alcohols gave a unique linear Anderson-Schultz-Flory with remarkable deviation of methanol.Thus,potassium promoter exerted a prominent function on the whole chain propagation to produce alcohols especially for the stage of methanol to ethanol.更多还原