The reactivity and properties of polyoxometalates (POMs) vary remarkably as a function of the kind of addenda atoms, so the design and synthesis of new mixed-addenda POMs is a promising approach for the further development of the POM-related areas. In the present work, the first Mo/Ta/W ternary mixed-addenda POM (NH4)41H7[K3(H2O)3(P2W15Ta3O62)6(Mo2O4CH3CO2)3(MoO3)2]·85H2O (1), which is composed of 6 {P2W15Ta3O62} linked by 3 {MoV 2O4(OOCCH3)+} and 2 {MoVIO3} via 18 novel Mo–O–Ta bridges has been synthesized. The precursor {P2W15Ta3}, which has lower redox potential, is crucial for the formation of 1. The red-brown solid sample of 1 shows strong absorption in the visible region. The visible-light responsive charge transfer from benzylamine to 1 was observed experimentally. 1 was proved to be an efficient photocatalyst under simulated sunlight (AM 1.5G) radiation for the oxidative coupling of primary amines to imines using atmospheric O2.

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Although the mechanism of coal tar hydrogenation technology has not been fully revealed, many enterprises have realized the industrialization of this technology through the reference of crude oil hydrogenation technology. Therefore, it will be very helpful for the development of this technology to present a research result close to industry. Based on four kinds of catalyst gradations, the hydrogenation experiments of different processes and a series of 1200 h long-term experiments were carried out in a four-tube fixed bed reactor with coal tar distillate (IBP ≈ 360 °C) as the raw material. First, based on the product composition of different reactor outlets, the composition changes and main reaction process of coal tar in four reactors were summarized. It was found that the reactions in the four reactions are different and related. The hydrogenation of olefins mainly takes place in the first reaction (230 °C, hydrofining guard catalyst and hydrodemetallization catalyst). Most of the oxygenated compounds were transformed in the second reactor (320 °C, hydrogenation catalyst I) but not completely. The hydrogenation of aromatics is mainly concentrated in the third and fourth reactors, but there are already signs of this reaction in the second reactor. Second, the influence of different process conditions on the product properties and the material balance under different process conditions were summarized. Finally, the stability of the grading system is verified by the long-term experiments.

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