The water resistance enhanced strategy of Mn based SCR catalyst by construction of TiO2 shell and superhydrophobic coating

Superhydrophobic surfaces have received enormous attention thanking to their potential applications in the areas of anti-icing, anti-contamination, and oil/water separation. Herein, we have successfully prepared superhydrophobic surfaces, which were synthesized by using the polydimethylsiloxane (PDMS) as adhesive and the magnesium palmitate (Mg-P) were evently coated to form roughness on the surfaces of glass, textile, stainless steel mesh, and paper. The as-fabricated superhydrophobic surfaces possessed excellent water-resistance, self-cleaning properties, durability, and robustness. Remarkably, in the actual oil/water separation, the water contact angle and oil collection efficiency of the superhydrophobic mesh were still more than 150° and 91% even after separation over 10 cycles, respectively. Thus, the superhydrophobic coating has applications potential in self-cleaning, anti-contamination, and oil/water separation fields.

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Influence of Superhydrophobic Coating on the Water Resistance of Foundry Dust/Magnesium Oxychloride Cement Composite

Materials ◽

10.3390/ma13153431 ◽

2020 ◽

Vol 13 (15) ◽

pp. 3431

Author(s):

Fajun Wang ◽

Xiantao Zhu ◽

Huangjuan Liu ◽

Sheng Lei ◽

Daqi Huang

Keyword(s):

Compressive Strength ◽

Water Resistance ◽

Cement Composite ◽

Superhydrophobic Coating ◽

X Ray Diffraction ◽

Aqueous Emulsion ◽

The Matrix ◽

Magnesium Oxychloride ◽

Magnesium Oxychloride Cement ◽

Oxychloride Cement

In this work, magnesium oxychloride cement (MOC) was used to realize the resource use of foundry dust (FD). Portland cement (PC)-based superhydrophobic coating was prepared on the surface of FD/MOC composite to improve the water resistance of the composite. First, the FD/MOC composites with different contents of FD were prepared. The phase structure of the composite was analyzed using X-ray diffraction (XRD). The microstructure of the cross-section and surface of the composite was observed using field emission scanning electron microscope (FE-SEM). The mechanical properties of the FD/MOC composites with different FD contents at different ages were tested and analyzed. Secondly, the superhydrophobic coating was prepared on the surface of MOC composite using silane/siloxane aqueous emulsion as the hydrophobic modifier, PC as the matrix and water as the solvent. The microstructure and chemical composition of the PC-based superhydrophobic coating were tested and analyzed. The results show that FD can significantly improve the early strength of the FD/MOC composite. The 28-day compressive strength of the FD/MOC composite decreases with increasing FD content. When the FD content is 30%, the 28-day compressive strength of the FD/MOC composite is as high as 75.68 MPa. Superhydrophobic coating can effectively improve the water resistance of the FD/MOC composite. The softening coefficient of the FD/MOC composite without superhydrophobic coating is less than 0.26, while that of the composite modified by superhydrophobic coating is greater than 0.81.

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Enhancing the Water Resistance of Mn-MOF-74 by Modification in Low Temperature NH3-SCR

Catalysts ◽

10.3390/catal9121004 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1004 ◽

Cited By ~ 1

Author(s):

Sheng Wang ◽

Qiang Gao ◽

Xiuqin Dong ◽

Qianyun Wang ◽

Ying Niu ◽

...

Keyword(s):

Low Temperature ◽

Polyethylene Oxide ◽

Water Resistance ◽

Catalytic Reduction ◽

Performance Tests ◽

Scr Catalyst ◽

Characterization Methods ◽

Structure And Morphology ◽

Nh3 Scr ◽

Low Temperature Scr

In this study, Mn-MOF-74 was successfully synthesized and further modified via two paths for enhanced water resistance. The structure and morphology of the modified samples were investigated by a series of characterization methods. The results of selective catalytic reduction (SCR) performance tests showed that polyethylene oxide-polypropylene-polyethylene oxide (P123)-modified Mn-MOF-74 exhibited outstanding NO conversion of up to 92.1% in the presence of 5 vol.% water at 250 °C, compared to 52% for Mn-MOF-74 under the same conditions. It was concluded that the water resistance of Mn-MOF-74 was significantly promoted after the introduction of P123 and that the unmodified P123-Mn-MOF-74 was proven to be a potential low-temperature SCR catalyst.

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Mechanical stability of superhydrophobic epoxy/silica coating for better water resistance of wood

Holzforschung ◽

10.1515/hf-2014-0077 ◽

2015 ◽

Vol 69 (3) ◽

pp. 367-374 ◽

Cited By ~ 19

Author(s):

Feng Liu ◽

Zhengxin Gao ◽

Deli Zang ◽

Chengyu Wang ◽

Jian Li

Keyword(s):

Epoxy Resin ◽

Water Resistance ◽

Mechanical Stability ◽

Water Immersion ◽

Silica Coating ◽

Immersion Test ◽

Water Repellent ◽

Functionalized Silica ◽

Superhydrophobic Coating ◽

Step Procedure

Abstract A three-step procedure has been developed for superhydrophobic coating on wood based on epoxy/silica materials in combination with hydrophobization. First, the epoxy resin is adhered to wood by immersing the samples into an epoxy resin acetone solution, then amino-functionalized silica particles are anchored by the epoxide groups, and finally, the created surface is modified by octadecyltrichlorosilane (OTS). The superhydrophobic surface not only is water repellent, as shown by the contact angle (CA) tests, but also decreases essentially the wood’s water absorption as determined by a 120-day water immersion test. The good mechanical stability of the coating was confirmed by a sand collision method.

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