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A durable and high-flux superhydrophilic-underwater superoleophobic oil-water separation membrane was prepared for effective oil-water separation by cellulose-starch-silica surface charging and hydrophilization. The surface properties of the composite coating nylon membrane were characterized by contact angle and scanning electron microscopy. The chemical structures of this membrane were confirmed by Fourier transform infrared spectroscopy and energy dispersive X-ray spectrometer. This membrane showed excellent hydrophilicity and underwater oleophobicity. After modified, the water contact angle of the membrane attained 0, and the underwater oil contact angles reached 159.5. The cellulose-starch-silica composite coating nylon membrane exhibited high oil-water separation efficiency (99.8%) for hexane, and it was also efficient for cyclohexane, petroleum ether, diesel, soybean oil, lubricating oil and silicone oil. Besides, the membrane flux could reach 31847 L−1m−2 h−1 bar−1. It showed this membrane had a high efficiency for oil-water separation. The modified nylon membrane was durable for oil-water separation. The separation efficiency could still retained above 97% after 100 cycles, and the modified nylon membrane still worked well after 24 h in harsh environment (pH value 4 to 10). The whole separation process could be achieved successfully without depending on any extra power. This work provided a new strategy to fabricate superhydrophilic and underwater superoleophobic membrane with good reusability, high flux and stability for oil-water separation.

In the field of selective catalytic reduction of nitrogen oxide, metal-species and loading-amount regulations were usually investigated to increase the catalytic activity. For the first time, this work investigated the influence of metal coordination state on the catalytic activity. Catalysts with different coordination states were compared by experiments and theoretical calculations. With the increase of coordination state, crystallinity improved, lone-pair-electron amount increased from 7.0∗104 to 1.5∗106, and catalytic-enter ability for electron donating enhanced from 0.376 to 0.430 |e−|. In comparison, oxide-state catalyst only showed a charge of 0.294 |e−|. As a result, the catalytic activity of oxide state was only 39.45% at 350 °C. The activity increased to 59.46, 76.75, and 98.62% in poor, weak, and good coordination state, respectively. If this result was applied in producing honeycomb catalyst, adding ligand increased the total price by 4%. However, the total cost was reduced by 48% for end users since increased activity decreased usage amount. After all, main results of this work will help to produce a more effective catalyst with a same metal-loading amount by controlling coordination state, which is in favor of both industrial and academic fields.