骨架镍的制备及其在染料中间体合成中的应用

Preparation of Raney nickel and its application in synthesis of dye intermediates

为满足清洁生产的要求,提高T酸合成的反应速率和转化率,以镍铝合金粉末作为催化剂前驱体,经过氢氧化钠活化制备骨架镍催化剂,借助扫描电子显微镜、X射线衍射仪、比表面积及孔隙分析仪和Zeta电位分析仪等手段对其结构和性能进行表征,并研究其在硝基T酸加氢还原制备T酸中的应用。结果表明:制备的骨架镍催化剂含有大量的孔道,以中孔为主,比表面积为46.88 m^2/g,平均晶粒尺寸为15.8 nm。制备的骨架镍在硝基T酸加氢还原中的最佳应用工艺为:催化剂质量分数2.500%,反应压力2.0 MPa,反应温度120℃,搅拌速度800 r/min。在此最佳工艺条件下,硝基T酸的转化率达99.07%,并且套用10次无明显失活现象。

In order to meet the requirements for clean production and to improve the reaction rate and conversion rate of T-acid synthesis,the nickel-aluminum alloy powder was used as the catalyst precursor to prepare the Raney nickel catalyst by sodium hydroxide activation.The prepared structure and properties of the materials were studied by means of scanning electron microscope,X-ray diffractometer,specific surface area and pore structure tester and Zeta potential tester,and so on,and its application in the preparation of T-acid by hydrogenation reduction of nitro T-acid was investigated.The results show that the prepared Raney nickel catalyst is rich in pore structures,mainly mesopores,with a specific surface area of 46.88 m^2/g and an average grain size of 15.8 nm.The optimum application process of the prepared Raney nickel in the hydrogenation reduction of nitro T-acid is as follows:catalyst dosage 2.500%,reaction pressure 2.0 MPa,reaction temperature 120℃,stirring speed 800 r/min.Under the best process conditions,the conversion of nitro T-acid reaches 99.07%,and there is no obvious deactivation after ten times of reuse.