本文選題：磁性納米材料 + 過渡金屬��； 參考：《北京化工大學(xué)》2016年碩士論文

【摘要】：磁性納米級催化劑不僅具備納米粒子的結(jié)構(gòu)與性能,還有磁性,使得催化劑具有高催化性能,且可回收再利用；貴金屬Pd價格高,而過渡金屬成本低、無毒,因此,制備出綠色環(huán)保、經(jīng)濟、活性高的催化劑已成為人們關(guān)注的熱點。此論文所使用的催化劑顆粒尺度為納米級,以磁性Fe304為磁核,以m-Si02@si02@Fe3O4為載體,為了實現(xiàn)對活性組分的良好負載,對二氧化硅層做了氨基修飾——m-siO2-NH2@SiO2@Fe3O4,最后成功制備了Cu/m-SiO2@SiO2@Fe3O4、Cu-Pd/m-SiO2@SiO2@Fe3O4、Co-Pd/m-SiO2@ SiO2@Fe3O4這三種催化劑。采用了XRD、FT-IR及TEM分析方法對三種催化劑進行了結(jié)構(gòu)表征。本文選擇碘苯和丙烯酸甲酯為Heck反應(yīng)模型研究催化劑的催化性能及重復(fù)使用性能。取得的結(jié)果如下：(1)制備出了粒子大小約為110nm、分散性能好的納米級Fe304微球；氨基修飾后的載體m-SiO2-NH2@SiO2@Fe3O4負載金屬更加均勻,不會發(fā)生團聚現(xiàn)象,所負載的Cu金屬顆粒直徑為2-4nm；(2)Cu/m-SiO2@SiO2@Fe3O4的催化性能良好,最佳的反應(yīng)條件為：Cu的負載量為17.5wt%時,碘苯：丙烯酸甲酯：堿為1：1.5：1.2(摩爾比),以DMF為溶劑,三乙胺為堿源,140℃下,反應(yīng)18h,反應(yīng)物碘苯的轉(zhuǎn)化率為55.16%。催化劑具有良好的回收使用性能,可重復(fù)利用3次；(3)Cu-Pd/m-SiO2@SiO2@Fe3O4的催化性能良好,最佳的反應(yīng)條件為：Pd的負載量為0.5wt%,Cu的負載量為4wt%時,碘苯：丙烯酸甲酯：堿(摩爾比)為1：1.5：1.2,DMF為溶劑,三乙胺為堿源,120℃下,反應(yīng)3h,碘苯的轉(zhuǎn)化率為99.55%,可重復(fù)利用5次；(4)Co-Pd/m-SiO2@SiO2@Fe3O4的催化性能良好,最佳的反應(yīng)條件為：Pd的負載量為0.5wt%,Co的負載量為6wt%時,碘苯：丙烯酸甲酯：堿(摩爾比)為1：1.5：1.2時,NMP為溶劑,三乙胺為堿源,120℃下,反應(yīng)3h,碘苯的轉(zhuǎn)化率為99.68%,可重復(fù)利用5次。
[Abstract]:Magnetic nanocrystalline catalysts not only possess the structure and properties of nanoparticles, but also have magnetic properties, which make the catalysts have high catalytic performance and can be recycled and reused. The price of noble metal PD is high, while the cost of transition metal is low, and the transition metal is non-toxic. The preparation of green, economical and highly active catalysts has become the focus of attention. The catalyst used in this paper is nanometer scale, magnetic Fe304 as magnetic nucleus, m-Si02@si02@Fe3O4 as carrier, in order to achieve good loading of active components. The SiO2 layer was modified with amino groups, m-siO2-NH2AlSiO2SiO2Fe3O4. Finally, three kinds of catalysts, Cu/ m-SiO2SiO2Fe3O4, Cu-PdR / m-SiO2SiO2Fe3O4 / Co-PdR / m-SiO2 @ SiO2@Fe3O4 were successfully prepared. The structure of the three catalysts was characterized by XRD- FT-IR and TEM. In this paper, Iodobenzene and methyl acrylate were selected as Heck reaction models to study the catalytic performance and reusability of the catalyst. The results obtained are as follows: (1) Fe304 microspheres with a particle size of 110 nm and good dispersion properties were prepared. The modified carrier m-SiO2-NH2@SiO2@Fe3O4 supported the metal more evenly without agglomeration. The supported Cu metal particle diameter is 2-4 nm ~ (-1) N ~ (-1) N ~ (2) O ~ (2 +) Cu / m -SiO _ (2) O _ (2) @ Sio _ (2) Fe _ 3O _ (4). The optimum reaction conditions are as follows: when the loading amount of 1: Cu is 17.5 wt%, the molar ratio of iodobenzene: methyl acrylate to alkali is 1. 5: 1.2 (mole ratio, DMF as solvent, triethylamine as alkali source, 140 鈩，

本文編號：1810399