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The anti-sand erosion and anti-icing coating technique is highly demanded in the leading edge of the airfoil surface. Herein, an anti-sand erosion and anti-icing coating (Si-PUEc) based on the silicone-modified polyurethane elastomer (Si-PUE) was fabricated and its hydrophobicity, tensile property, sand erosion resistance and anti-icing performance were investigated. The polyurethane elastomer was synthesized by a polyaddition reaction of hydroxy-terminated polyolefin resin and polyolefin resin as soft segments with isophorone diisocyanate and 1,4-butanediol as hard segments. The research results show that the Si-PUEc with a high water contact angle (WCA) of 108° exhibits a weak ice adhesion strength of 68.04 kPa, less than a third of that of the original bare aluminum plate surface (235.26 kPa). Moreover, the tensile strength of Si-PUEc is 14.03 MPa and the elongation at break is 370%, showing excellent tensile properties. After the sand and dust test, the surface of Si-PUEc is intact, without damage, cracking and other defects of the film, and the WCA remains at 108°. Before and after the damp-heat test, the hydrophobic performance, anti-icing performance, and stress-strain performance of Si-PUEc are not changed significantly. The distinctive composition and morphology of the polyurethane elastomer serves as the key that opens up a new strategy to design hydrophobic coatings for robust and durable anti-sand erosion and anti-icing coating applications in the leading edge of the airfoil surface.

Aiming at the high efficiency leaching of W and V in a SCR denitration catalyst, the microwave assisted leaching of W and V in waste SCR catalyst was studied. The results show that under the conditions of microwave power of 600 W, reaction time of 1 h, reaction temperature of 60 °C, sodium hydroxide concentration of 40% and liquid volume/solid mass ratio of 7.5/1, the leaching rates of W and V in SCR denitration catalyst can reach 89.96% and 96.32 %, respectively. After leaching the alkaline leaching residue with 4 mol/L HC1 solution for 1 h, TiO2 with a purity of 98.76% is obtained. Compared with the traditional water bath heating method, microwave heating leaching method can not only improve the leaching rate of tungsten and vanadium on SCR denitrification catalyst, but also greatly shorten the test reaction time, which provides a reliable technical basis for the green effective leaching of W and V in SCR denitrification catalyst. [ABSTRACT FROM AUTHOR]