材料期刊网

采用简便的化学浸渍法制备了新型磁性可分离的纳米复合物H5PMo10V2O40/Fe3O4/g-C3N4(PMoV/Fe3O4/g-C3N4),并进行了详细的表征,采用电位滴定法测定了催化剂酸性.该PMoV/Fe3O4/g-C3N4纳米复合物在硫化物选择氧化为砜或亚砜的反应中表现出较高的催化活性;考察了在优化反应条件下,它在含硫(包括二苯并噻吩DBT)模拟油或真实石油的催化氧化反应中的催化性能;特别考察了各种含氮化合物,以及1-环和2-环芳香烃作为共溶剂对DBT脱硫效果的影响.采用外加磁场即可方便地将该催化剂从反应混合物中分离和回收.选取最好的萃取剂,通过简单的倾滤就可很容易地将剩余反应物从产物中分离出来.该纳米催化剂具有高催化活性,且容易重复使用,至少可以重复使用4次而未见催化活性明显下降.

A facile approach to the preparation of a novel magnetically separable H5PMo10V2O40/Fe3O4/g-C3N4 (PMoV/Fe3O4/g-C3N4) nanocomposite by chemical impregnation is demonstrated. The prepared nanocomposite was characterized and its acidity was measured by potentiometric titration. PMoV/Fe3O4/g-C3N4 showed high catalytic activity in the selective oxidative desulfurization of sul-fides to their corresponding sulfoxides or sulfones. The catalytic oxidation of a dibenzothiophene (DBT)-containing model oil and that of real oil were also studied under optimized conditions. In addition, the effects of various nitrogen compounds, as well as the use of one- and two-ring aromatic hydrocarbons as co-solvents, on the catalytic removal of sulfur from DBT were investigated. The catalyst was easily separated and could be recovered from the reaction mixture by using an external magnetic field. Additionally, the remaining reactants could be separated from the products by sim-ple decantation if an appropriate solvent was chosen for the extraction. The advantages of this nanocatalyst are its high catalytic activity and reusability; it can be used at least four times without considerable loss of activity.