Abstract:

In the process of rare earth extraction and separation，a large amount of oily wastewater needs to be treated urgently. The super hydrophilic-underwater super oleophobic filtration membrane has brought a new solution for the oily wastewater of rare earth smelting. Based on filter cotton，polyvinyl alcohol （PVA） rich in hydroxyl and hydrophilic nano silica sol were used as precursor，and glutaraldehyde was used as crosslinking agent. The contact angle test showed that the contact angle to water in the air medium was 0°，and the contact angle to oil in the water medium was 155.3°. It had excellent super hydrophilic-underwater super oil-phobic properties. The oil and water separation experiments on the prepared PVA type superhydrophilic and underwater superoil hydrophobic filter membrane showed that the average oil and water separation rate of the filter membrane was 97.5% and the membrane flux was 11.89 L/（m²·s）. After 3 times of oil and water separation cycle tests，the filtration membrane still had 95.3% oil-water separation rate and 11.06 L/ （m²·s） membrane flux，showing good durability and stability，and had a certain prospect of industrial application.

Key words: polyvinyl alcohol, super hydrophilic, underwater super oleophobic, oily wastewater

摘要：

稀土萃取分离生产过程中会产生大量的含油废水亟待处理，超亲水-水下超疏油过滤膜为稀土冶炼含油废水带来了新的解决方案。以过滤棉为基材，以富含羟基的聚乙烯醇（PVA）与亲水的纳米二氧化硅溶胶为前驱体，以戊二醛为交联剂制备了PVA型超亲水-水下超疏油过滤膜。接触角测试表明，在空气介质中对水的接触角为0°，在水介质中对油的接触角为155.3°，具备优良的超亲水-水下超疏油性能。对制备的PVA型超亲水-水下超疏油过滤膜进行油水分离实验发现，3次重复实验过滤膜的平均油水分离率为97.5%，膜通量为11.89 L/（m²·s），经30次油水分离循环测试，该过滤膜仍具有95.3%的油水分离率和11.06 L/（m²·s）的膜通量，展现了较好的耐久性和稳定性，具有一定的工业推广应用前景。

关键词: 聚乙烯醇, 超亲水, 水下超疏油, 含油废水

CLC Number: 

• X703