In a double emulsion, the cross contamination between internal and external phase is an unavoidable problem, which limits its widely application. This work focused on the preparation of the cross contamination-free O/W/O Pickering emulsions for the fabrication of Pickering emulsion hydrogel (PEHG) microbeads encapsulating copper extractants. KH-570 was used to hydrophobically modify silica for the stabilization of O/W Pickering emulsions. Batch and fixed-bed experiments were conducted for the recovery of Cu(Ⅱ) from water using PEHG microbeads. The results showed that the formed particle-polymer networks in oil-water interface strengthen the stability of O/W Pickering emulsions. The cross contamination ratio of O/W/O Pickering emulsions was reduced to less than 3% under preset conditions. The size of PEHG microbeads was controlled by adjusting the dosage of hydrophobic silica and the optimal diameter used in extraction was 1.8–2.2 mm. The extraction capacity of copper extractants in PEHG microbeads was 86.43 mg/g, with the operation time of 80 min (D = 1.8 mm). The fixed-bed extraction experiment was completed in 250 min and the stripping rate was 97.1%. Compared to previous work, the extractants in PEHG microbeads possessed a better utilization.

在复乳液中，内相和外相之间的交叉污染是一个不可避免的问题，限制了其广泛应用。这项工作的重点是制备无交叉污染的 O/W/O Pickering 乳液，用于制造封装铜萃取剂的 Pickering 乳液水凝胶 (PEHG) 微珠。KH-570 用于对二氧化硅进行疏水改性，以稳定 O/W Pickering 乳液。使用 PEHG 微珠从水中回收 Cu(Ⅱ) 进行了批量和固定床实验。结果表明，油水界面形成的颗粒-聚合物网络增强了O/W Pickering乳液的稳定性。在预设条件下，O/W/O Pickering 乳液的交叉污染率降低到 3% 以下。PEHG 微珠的大小通过调节疏水二氧化硅的用量来控制，用于提取的最佳直径为 1.8-2.2 mm。PEHG微珠中铜萃取剂的萃取量为86.43 mg/g，操作时间为80 min (D = 1.8 mm)。固定床萃取实验在250 min内完成，汽提率为97.1%。与之前的工作相比，PEHG 微珠中的萃取剂具有更好的利用率。