Pt-Cr-SO_(4)^(2-)/ZrO_(2)的制备及其催化硝基苯加氢制备对氨基苯酚的研究

Preparation of Pt-Cr-SO_(4)^(2-)/ZrO_(2) and its catalytic hydrogenation of nitrobenzene to p-aminophenol

采用等体积浸渍法,以ZrO_(2)为载体制备了Pt-Cr-SO_(4)^(2-)/ZrO_(2)催化剂。考察了硫酸浸渍浓度、焙烧温度及助剂对Pt-Cr-SO_(4)^(2-)/ZrO_(2)催化硝基苯加氢制备对氨基苯酚的影响。对催化剂进行了BET、XRD、TG和IR表征,试验结果表明:(w)Pt为3%、硫酸浸渍浓度0.5 mol/L、焙烧温度600℃、Cr为助剂是Pt-Cr-SO_(4)^(2-)/ZrO_(2)制备的最优条件。在反应温度150℃、压力0.5 MPa、催化剂用量0.08 g和反应时间8 h的工艺条件下加氢效果最好,硝基苯的转化率为85.81%,对氨基苯酚的选择性为60.93%。

Pt-Cr-SO_(4)^(2-)/ZrO_(2) catalyst is prepared by equal volume impregnation with ZrO_(2) as carrier.The effects of sulfuric acid loading concentration,calcination temperature and additives on the hydrogenation of nitrobenzene to p-aminophenol catalyzed by Pt-Cr-SO_(4)^(2-)/ZrO_(2) are investigated.The catalyst is characterized by BET,XRD,TG and IR.The experimental results show that the optimum conditions for the preparation of Pt-Cr-SO_(4)^(2-)/ZrO_(2) are as follows:w(Pt)is 3%,sulfuric acid loading concentration is 0.5 mol/L,calcination temperature is 600℃,Cr is used as promoter.The hydrogenation effect is the best under the process conditions of reaction temperature 150℃,pressure 0.5 MPa,catalyst dosage 0.08 g and reaction time 8 h.The conversion of nitrobenzene is 85.81%and the selectivity of p-aminophenol is 60.93%.