Study On The Synthesis Of 2,6-dimethylaniline With 2,6-dimethylphenol By Gas Phase Amination

The current researching of 2,6-dimethylaniline at home and abroad was reviewed in this paper. The process of synthesizing 2,6-dimethylani line with 2,6-dimethylphenol, gaseous ammonia and hydrogen by vapor phase animation was studied. The optimum catalyst was selected and the effect of process conditions on this reaction was discussed. The catalyst was characterized by XRD and the physical structure was measured.In the part of catalyst's evaluation, the main catalyst Pd was selected at first and the influence of the content of Pd on the catalytic activity was investigated. Secondly, the effect of supporting material on the activity of palladium was studied, especially, the effect of spinel MgAl2O4 support. Moreover the modification of the supported palladium catalyst by alkali metal oxide and rare earth oxides was studied and the effect of pore-enlarging experiment on catalytic activity was investigated. The catalyst affirmed eventually is Pd[0.5%(wt)]/spinel[(wt)(Y-Al2O3):(MgO):(Al2O3) =50:1:4].In the part of optimizing process conditions, the influence of reaction temperature, feed ratio and contact time was discussed. The optimum process condition selected is as follows: reaction temperature 250 , molar feed ratio 2,6-dimethylphenol:ammonia:hydrogen=l:10:10, F/W=0.0205 mol ?g-1 ?hr-1. Under the optimum process conditions the conversion of 2,6-dimethylphenol is larger than 73% and the selectivity to 2,6-dimethylaniline is larger than 94%.In brief, the synthesis of 2.6-dimethylaniline with ammonia, hydrogen and 2,6-dimethylphenol by vapor phase amination was studied systematically in this paper. All of this provided the theoretical foundation and scientific basis for industrialization.Sun Ronghua (Chemical Engineering) Directed by associate professor Zhang Xiucheng...