利用介孔氧化硅SBA-15浸渍吸附合成硅铁红色料

摘要

以P123为表面活性剂,采用水热法合成了高度有序介孔二氧化硅SBA-15,然后通过浸渍吸附硝酸铁溶液并600 ℃煅烧的方法合成了介孔氧化硅负载α-Fe2O3的硅铁红色料.利用XRD、TEM、比表面仪等分析方法对样品的晶体结构、微观结构、比表面积和孔径等进行表征.结果表明:水热法合成的介孔二氧化硅具有二维六方结构,其比表面积为609.318 6 m2/g,平均孔径为5.43 nm.合成过程中水热温度的升高会影响模板剂P123的溶解性,致使介孔氧化硅的比表面积减少,孔径增大.负载α-Fe2O3后介孔氧化硅N2吸附量明显降低,孔体积减小,但孔径尺寸未发生变化,证实了α-Fe2O3进入了介孔氧化硅的孔道.由于介孔孔道的限制,合成的α-Fe2O3颗粒为纳米级,所以硅铁红色料呈现较好的红褐色.%The highly ordered mesoporous silica SBA-15 was synthesized by hydrothermal method,using P123 as surfactant agent.The hematite-silica red pigment of α-Fe2O3 loaded mesoporous silica was synthesized through mesoporous silica impregnated and adsorbed in Fe(NO3)3 solution,then calcined at 600 ℃.The crystals structure,microstructure,specific surface area and pore size distribution of samples were characterized by XRD,TEM and BET.The results show that the mesoporous silica with hexagonally ordered pore array structure was synthesized by hydrothermal method.Its specific surface area was 609.318 6 m2/g and its average pore size 5.43 nm.In synthesis process,the dissolubility of the template agent P123 was influenced by hydrothermal temperature,leading to the specific surface area of the mesoporous silica decrease and pore size increase.The N2 absorption quantity and pore volume of the mesoporous silica obviously decrease after loading α-Fe2O3,yet its pore size have no change.The fact confirm that α-Fe2O3 enter into mesoporous canal of the mesoporous silica.Since the α-Fe2O3 chromophore were restricted in mesoporous canal,the particles size of the synthesized α-Fe2O3 is nanometer,and the hematite-silica red pigments present good reddish-brown.