基于静电喷雾法制备油水分离的超疏水表面研究

目的 提出一种静电喷雾法制备超疏水表面而实现油水分离的方法。方法 利用静电喷雾法将二氧化硅微粒喷涂到不锈钢网表面以构建微粗糙结构，利用氟硅烷降低二氧化硅微结构涂层的表面能。探讨静电喷雾的电压、喷涂时间、二氧化硅粒径、溶液pH、浸泡时间等参数，对表面微结构和疏水性能的影响。通过扫描电镜表征样件表面形貌，通过接触角测量仪测量超疏水不锈钢网表面的疏水性能。利用超疏水不锈钢网实现油水分离以检验装置的浮油收集能力。结果 二氧化硅微粒能够在不锈钢网表面喷涂形成均匀粗糙的微结构。在6 kV静电压下，雾化喷涂粒径为25 nm的二氧化硅所获得的超疏水不锈钢网的接触角达161°，在不同pH溶液中浸泡15 d后，接触角仍大于150°，浸泡35 d后，接触角仍大于未处理的不锈钢网。该网可以收集97%以上的柴油和煤油及90%以上的汽油和茶油，且重复使用20次后，仍保持粗糙的表面微结构和高油水分离率。结论 采用静电喷雾法能简单高效地获得超疏水表面，且具有较好的化学稳定性和有效的油水分离能力，具有很广的应用前景。

Preparation of Superhydrophobic Surface for Oil-Water Separation Based on Electrostatic Spray Method

The work aims to propose an electrostatic spray method for preparing superhydrophobic surfaces to achieve oil-water separation. The SiO2 particles were sprayed onto the stainless steel mesh surface by electrostatic spray method to construct the rough microstructure, and the surface energy of the SiO2 microstructure was reduced by flusilane. The effects of different electrostatic spraying voltage, spraying time, SiO2 particle size, solution pH and immersion time on surface microstructure and hydrophobicity were discussed. The surface morphologies of the samples were characterized by scanning electron microscope. The contact angles of superhydrophobic stainless steel mesh were measured by contact angle meter to evaluate hydrophobicity. Oil-water separation experiment was conducted by superhydrophobic stainless steel mesh to test the oil-water separation capacity. The SiO2 particles sprayed on the surface of stainless steel mesh could form uniform microstructures. The contact angle of the superhydrophobic mesh obtained by spraying 25 nm SiO2 particles under 6 kV voltage reached 161°. The contact angle was still greater than 150° after immersion in different pH solutions for 15 days, and greater than that of the untreated stainless steel mesh after 35 days. The mesh could collect more than 97% diesel and kerosene, 90% gasoline and tea oil from water, and it could retain rough microstructure and high oil-water separation after 20 times. Superhydrophobic surface can be prepared simply and efficiently by electrostatic spray method, and it has good chemical durability, effective oil-water separation ability and broad application prospects.