Ecologically friendly conversion coatings with special wetting behaviors for wax prevention

Superhydrophilicity and underwater superoleophobicity are fundamental issues in many applications for special wettable surfaces. In this work, special wetting behaviors were achieved by using an ecologically friendly wet chemical method. The prepared coatings with porous structure present superhydrophilicity and underwater superoleophobicity. The effects of the reaction conditions, such as pH values and conversion duration, on the morphology and wetting behaviors of the prepared coatings were also studied. A wax deposition test based on the cold-finger method was carried out and good performance was displayed. A possible wax prevention mechanism is proposed, which can be calculated from water film theory. The corrosion resistance and stability of the prepared coatings were also measured. The prepared coatings with special wetting behaviors offer significant insight into the design of anti-wax materials in crude oil transition.