One-step fabrication superhydrophobic sand filter for capillary-driven separation of water-in-oil emulsions

doi:10.1016/j.cjche.2020.07.012

Abstract

Abstract: The efficient separation of water-in-oil emulsion is of significance in environment and energy filed, and it has become a world-wide challenge. Herein, we have presented a one-step, facile and low-cost approach to prepare superhydrophobic sands for efficient separation of water-in-oil emulsion. The as-prepared sand layers possessed a water contact angle higher than 151°, demonstrating their superior superhydrophobic property. Besides, the as-prepared sand layers could separate water-in-emulsions with separation efficiency up to 99.7%, which is superior to both traditional and superwettable filtration membranes. The effect of thickness of sand layer on separation performance was also investigated. The results showed that the filtration flux decreased with the increased of filtration thickness while the separation efficiency increased. The as-prepared sand layer proposed by this study is a processing candidate for separating water-in-oil emulsion in practical industry. Additionally, the as-prepared superhydrophobic sand fabrication method also provides an alternative for desert water storage.

Key words: Separation, Filtration, Superhydrophobic sand, Preparation, Emulsion

摘要： The efficient separation of water-in-oil emulsion is of significance in environment and energy filed, and it has become a world-wide challenge. Herein, we have presented a one-step, facile and low-cost approach to prepare superhydrophobic sands for efficient separation of water-in-oil emulsion. The as-prepared sand layers possessed a water contact angle higher than 151°, demonstrating their superior superhydrophobic property. Besides, the as-prepared sand layers could separate water-in-emulsions with separation efficiency up to 99.7%, which is superior to both traditional and superwettable filtration membranes. The effect of thickness of sand layer on separation performance was also investigated. The results showed that the filtration flux decreased with the increased of filtration thickness while the separation efficiency increased. The as-prepared sand layer proposed by this study is a processing candidate for separating water-in-oil emulsion in practical industry. Additionally, the as-prepared superhydrophobic sand fabrication method also provides an alternative for desert water storage.

关键词: Separation, Filtration, Superhydrophobic sand, Preparation, Emulsion

Bao Wang, Chaolang Chen, Zhaoxin Li, Jianfeng Wu, Xianglou Liu, Jiadao Wang. One-step fabrication superhydrophobic sand filter for capillary-driven separation of water-in-oil emulsions[J]. Chinese Journal of Chemical Engineering, 2021, 33(5): 70-75.

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