同多钨酸根柱撑镍铝水滑石的原位合成

采用原位沉积法在γ-Al₂O₃表面原位合成了对苯二甲酸阴离子柱撑的镍铝水滑石，并用同多钨酸根阴离子部分交换了镍铝水滑石中的对苯二甲酸阴离子。用XRD，BET， FT-IR和TG-DTA等测试方法对材料进行表征。结果表明，经过同多钨酸根阴离子的交换以后，垂直于水滑石层板方向的平行层板方向的晶格参数(c)值变小，平行层板方向的晶格参数(a)值不变，(003)、(006)、(009) 衍射峰处的层间距(d)值比为3∶2∶1；交换过程没有改变水滑石的结构，水滑石原位生长在γ-Al₂O₃表面及内孔，比表面积由γ-Al₂O₃载体的219m²/g增加到247m²/g，孔径分布则由原来的2～11nm变化为3～4nm。

In-situ synthesis of polytungstate anion-pillared Ni-Al hydrotalcite

A terephthalate anion-pillared Ni-Al hydrotalcite-like layered double hydroxide (LDH) was synthesized on the surface and within the pores of γ-Al₂O₃ by in situ crystallization and a polytungstate anion-pillared hydrotalcite was subsequently obtained by ion-exchange. The materials were characterized by XRD, BET, FT-IR and TG-DTA. XRD indicated that the replacement of the terephthalate anion by the polytungstate anion had little effect on the structure. FT-IR spectra suggested that a strong interaction was present between γ-Al₂O₃ and the hydrotalcite. N₂ adsorption measurements showed that the surface area of the LDHs/γ-Al₂O₃ composite was 247m²/g, higher than that of γ-Al₂O₃ (219m²/g), whilst the pore diameter (3-4nm) was lower than that of γ-Al₂O₃ (2-11nm). Therefore, it can be concluded that nanosized crystals of LDHs are located on both the surface and within the pores of γ-Al₂O₃. The properties of the material make it a good candidate for a hydrodesulfurization catalyst. 