Study On The Performance And Mechanism Of Super Hydrophobic Coating Containing Hydroxyl To Inhibit Hydrate Nucleation

With the rapid development of economic,the demand for oil and gas is increasing day by day,which puts forward higher requirements to the efficient transportation of oil and gas in pipeline.But during the exploitation and transportation of oil and gas,it is easy to form hydrate and cause pipeline blockage,which inflicts serious damage on the economic.Therefore,it is of great significance to find a method to prevent hydrate from blocking pipelines.The traditional methods of preventing hydrates from blocking pipelines,including physical methods such as adiabatic method and chemical methods such as adding thermodynamic inhibitors,are difficult to meet the requirements of practical application due to the disadvantages of complex equipment and process,high cost,low safety,low applicability and universality.Superhydrophobic surfaces have great potential in liquid transportation due to their low adhesion.However,superhydrophobic surface can promote hydrate nucleation,which limits its application in the transportation of oil and gas.Therefore,it is a great challenge to develop a superhydrophobic surface that can not only inhibit hydrate nucleation but also prevent hydrate from sticking to the pipeline.To find a preparation method of superhydrophobic interfacial materials that can inhibit the nucleation of hydrate,the effects of interfacial materials which containing hydrophilic groups(hydrophilic chains)on nickel substrate on hydrate nucleation,were studied by molecular dynamics simulation.Molecular dynamics simulation shows that the interfacial materials containing hydrophilic groups can inhibit hydrate nucleation better than pure nickel interfacial materials.The reason is that the hydrophilic groups introduced into the organic chain segment can disturb the ordered arrangement of water molecules,form hydrogen bonds with water molecules,reduce the number of hydrogen bonds between water molecules,and reduce the stability of hydrate cage.In this study,the reliability of molecular dynamics simulation was proved by combining experimental study with computational simulation.The result shows that introducing hydrophilic groups on the surface of interfacial materials is a feasible method for inhibiting hydrate nucleation.Based on the above research,hydroxyl was introduced into the POSS based superhydrophobic resin system and mixed with hydrophobic silica to construct a hydroxy superhydrophobic coating with inhibiting hydrate nucleation properties.Molecular dynamics simulation study found that,compared with superhydrophobic coating that not containing hydroxyl,superhydrophobic coating that containing hydroxyl can disturb the ordered arrangement of water molecules,reduce the formation of hydrate cage,preferentially form hydrogen bonds with water molecules,reduce the number of hydrogen bonds between water molecules and reduce the life of these hydrogen bonds,thereby inhibit hydrate nucleation.The further experimental study confirmed that the superhydrophobic coating containing hydroxyl group could not only inhibit hydrate nucleation but also prevent hydrate adhesion,which verified the reliability of the simulation study.The research can provide theoretical guidance for the application of superhydrophobic coating in preventing hydrate from blocking pipelines.