钝化Ni/HY催化剂催化2,4-二硝基甲苯加氢合成2,4-二胺基甲苯

采用浸渍沉淀法制备了Ni/HY催化剂,用BET,FTIR,XRD,TEM,SEM,XPS,H2-TPR,H2-TPD等方法对催化剂进行了表征,并将其用于2,4-二硝基甲苯(2,4-DNT)液相加氢合成2,4-二胺基甲苯(2,4-TDA)反应,考察了反应条件对合成反应的影响。表征结果显示,Ni/HY催化剂的活性组分在载体表面以氧化镍的形式存在,在体相中以单质Ni的形式存在,在2,4-DNT加氢反应中活性组分基本没有流失。合成2,4-TDA的实验结果表明,Ni/HY催化剂具有较高的活性,在2,4-DNT用量5 g、反应时间1.25 h、m(乙醇)∶m(2,4-DNT)=50、m(催化剂)∶m(2,4-DNT)=0.10、反应压力2.2 MPa、搅拌转速750 r/min、反应温度90℃的条件下,2,4-DNT的转化率和2,4-TDA的选择性分别为99.88%和99.16%;该催化剂活性组分分散度高,稳定性好,循环使用3次后仍能保持良好的催化性能。

Hydrogenation of 2,4-Dinitrotoluene to 2,4-Tolylenediamine over Passivated Ni/HY Catalyst

A novel passivated Ni/HY catalyst were prepared by impregnation-precipitation method and characterizated by means of BET,FTIR,XRD,TEM,SEM,XPS,H2-TPR and H2-TPD.The results indicated that the active component on the support surface existed in the form of nickel oxide.There was little loss of the active components in catalytic hydrogenation of 2,4-dinitrotoluene(2,4-DNT) in liquid phase to 2,4-tolylenediamine(2,4-TDA).Under the optimum reaction conditions of 4-DNT dosage 5 g,reaction time 1.25 h,m(ethanol sol...