单层型氧化铁催化剂的制备及其前体的表征Ⅰ．催化剂前体的制备

PREPARATION OF MONOLAYER FERRIC OXIDE CATALYSTS AND CHARACTERIZATION OF THEIR PRECURSORS Ⅰ.PREPARATION OF THE CATALYST PRECURSORS

尝试用（ＮＨ４）３［Ｆｅ（Ｃ２Ｏ４）３］·ＸＨ２Ｏ的过量水溶液含浸法制备不同载体上单层型氧化铁催化剂．为了比较，也采用Ｆｅ（ＡｃＡｃ）３的甲苯溶液热吸附以及Ｆｅ（ＮＯ３）３溶液饱和浸渍两种方法制备样品．特别对合浸法，考察了含浸溶液的ｐＨ值、浓度及含漫时间对吸附过程的影响，确定了不同载体催化剂前体的适宜制备条件．

A controllable impregnation method with the dipping of supportinto an excess of aqueous solution of (NH4)3 [Fe (C2O4)3]. XH2O wasadopted to prepare welldispersed or monolayer type ferric oxide on various supports. Other two methods, i. e., batch adsorption of Fe (AcAc)3in toluene at 398K and incipient wetness impregnation with Fe(NO3)3solution were also used to make a comparison. The influences on the adsorption process were investigated and the suitable conditions were determined for the different supported systems. It was found that themonolayer type ferric oxide on Y-Al2O3 TiO2 and ZrO2 could be satisfactorily prepared by dipping support into an excess of (NH4)3 [Fe(C2O4)3]. XH2O solution and batch adsorption of Fe (AcAc)3 intoluene. The impregnation with Fe (NO3)3 solution, however, was notideal for the preparation of well-dispersed catalyst.