Research On The Fabrication Method And Application Of The Extreme Wettability Oil/Water Separation Screen

The water environment and ecosystem are seriously threatened by spilled oil on the sea and oily wastewater produced by industrial & family.Therefore,how to separate oil from oil/water mixture efficiently is an urgent engineering problem.The special wettability oil/water separation screen,basing on the differences of oil and water wettability on the surface,provides a new solution.Anodizationprocessing and laser processing are common mechanical surface processing methods.And copper alloy is one of the most commonly applied industrial materials.In this work,the special wettability oil/water separation screens were fabricated using one-step anodization method and laser processing combined with long-chain silane modification method based on cooper matrix and copper foam matrix.This work mainly includes following contents:The copper mesh was selected as fabrication matrix.The three-factor and four-level orthogonal experiment was designed and the range method was used to get optimal combination of anodization parameters.The special wettability oil/water separation screen with superhydrophobic and superroleophilic surface property was fabricated.The water contact angle and sliding angle tended to 153.0±2.3° and 7.5°,respectively,meanwhile,the oil droplet could be absorbed completely in 2.6 s,and the oil contact angle tended to 0°.The micro/nano binary roughness structure was formed on the fabricated screen.The chemical composition on the fabricated screen was mainly copper myristate.Compared with original copper mesh matrix,the corrosion current density of the fabricated screen decreased by an order of magnitude,which means the fabricated screen exhibited excellent anti-corrosion property.The fabricated screen still exhibited hydrophobic property after peel test,friction and soaking experiment,respectively,which means the fabricated screen exhibited good surface mechanical stability.An oil/water separation device was designed according to the “water sliding,oil dropping” principle based on the fabricated screen via one-step anodization method.The efficiency of oil/water mixtures separated by the fabricated screen were all above 92%.Even after 10 cycles,the efficiency was still above 87.And the separated oil had good purity.The copper foam was selected as fabrication matrix.The copper foam surface was designed through regulating laser maker's laser speed,power and pacing to construct the surface micro structure satisfying Cassie wettability model.Dodecyltrimethoxysilane molecule self-assembled was used to generate low surface energy coating in the surface.The special wettability oil/water separation screen with superhydrophobic and superroleophilic surface property was fabricated.The water contact angle and sliding angle tended to 151.3±0.6° and 8.5°,respectively,meanwhile,the oil permeability was good,the oil droplet could be absorbed completely in 1.7 s,and the oil contact angle tended to 0°.Compared with fabricated screen via one-step anodization method,the fabricated screen via laser processing method had higher corrosion resistance and mechanical stability.An oil/water separation device was designed according to the “water prevented,oil passing” principle based on the fabricated screen via laser processing method.The efficiency of oil/water mixtures separated by the fabricated screen were all above 87%.Even after 10 cycles,the efficiency was still above 85.And the separated oil had good purity.The characteristics and application fields of the special wettability oil/water separation screen prepared via one-step anodization method and laser processing method were compared and analyzed,which provided the reference for the popularization and application of the special wettability oil/water separation screen.