A low-cost mullite-titania composite ceramic hollow fiber microfiltration membrane for highly efficient separation of oil-in-water emulsion. (1st March 2016)

• Record Type: Journal Article
• Authors: Zhu, Li; Chen, Mingliang; Dong, Yingchao; Tang, Chuyang Y.; Huang, Aisheng; Li, Lingling
• Is Part Of: Water research. Volume 90(2016)
• Page Start: 277
• Page End: 285
• Publication Date: 2016-03-01
• Subjects: Oil-in-water emulsion -- Ceramic membrane -- Hollow fiber membrane -- Mullite-titania composite membrane -- Solid waste recycling; Water -- Pollution -- Research -- Periodicals; 363.7394
• DOI: 10.1016/j.watres.2015.12.035
• Languages: English
• ISSNs: 0043-1354

Abstract

Abstract: Oil-in-water (O/W) emulsion is considered to be difficult to treat. In this work, a low-cost multi-layer-structured mullite-titania composite ceramic hollow fiber microfiltration membrane was fabricated and utilized to efficiently remove fine oil droplets from (O/W) emulsion. In order to reduce membrane cost, coal fly ash was effectively recycled for the first time to fabricate mullite hollow fiber with finger-like and sponge-like structures, on which a much more hydrophilic TiO2 layer was further deposited. The morphology, crystalline phase, mechanical and surface properties were characterized in details. The filtration capability of the final composite membrane was assessed by the separation of a 200 mg·L −1 synthetic (O/W) emulsion. Even with this microfiltration membrane, a TOC removal efficiency of 97% was achieved. Dilute NaOH solution backwashing was used to effectively accomplish membrane regeneration (∼96% flux recovery efficiency). This study is expected to guide an effective way to recycle waste coal fly ash not only to solve its environmental problems but also to produce a high-valued mullite hollow fiber membrane for highly efficient separation application of O/W emulsion with potential simultaneous functions of pure water production and oil resource recovery. Graphical abstract: Highlights: Coal fly ash was effectively recycled to fabricate mullite hollow fiber. The membrane has high TOC removal efficiency for oil-in-water emulsion treatment. Simultaneous function of water production and oil resource recovery was achieved.