| Methanol,ethanol is not only an useful organic chemical materials,but also an important basic organic raw material.Farm insecticide,medical,dyestuff, spice,covering material and composite material all need methanol and ethanol for dissolvant and raw stuff.Nowadays,because of development of technological and change of energy structure,methanol and ethanol are establishing many new purpose.Alcohol as bunkers have merit of high combustion value,low CO,NOX,hydrocarbon emission.In this paper,a series of CuZnAl slurry catalysts suitable for slurry-bed process were prepared by a complete liquid-phase technology.And slurry catalyst which was prepared by this technology was used in the synthesis of MEOH,ETOH from synthetic gas. The catalyst was modified by different kinds of surfactant.The catalysts were characterized by XRD,N2 adsorption,XPS,TPR,SEM and size analysis,the catalytic activity of catalysts for direct synthesis of MEOH,ETOH from syngas were evaluated in a slurry reactor.The effect of different surfactants on structure of catalysts and catalytic performance was investigated.According to the experiment of different kinds of surfactant,we approach catalyst was modified by different preparation method and assistant.The experimental results come to following conclusions:①The CuZnAl slurry catalyst which was prepared by a complete liquid-phase technology have a high activity and a good stability.The catalyst adding polyvinylpyrrolidone(pvp)was prepared by hydrolyse method has a high selectivity of ETOH,reaching 40%.②The results show that,the copper of catalyst was in the form of Cu0 and Cu+.③The ZnO of catalyst surface can adsorb H2 or CHx,and increase activity of catalyst.The catalyst which is adding pvp adsorbs maximum H2 or CHx,so this catalyst has best activity.④The predecessor body of catalyst which was prepared by a method of alcoholysis has a higher activity,and the catalyst adding nonionic surfactant has a best activity,a high conversion of CO which reaching 36%.This catalyst has a excellent selectivity to MEOH.⑤The specific surface area of catalyst which was prepared by a method of alcoholysis is biger than the catalyst which was prepared by a method of hydrolyse,and has stable phase structure and pore structure.⑥The slurry catalyst with assistant is unfavourable for conversion of CO,but the slurry catalyst with potassium is favourable for selectivity to MEOH and the slurry catalyst with carbon nanotobes is favourable for selectivity to ETOH.
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