title: Breathing Demulsification: A Three-Dimensional (3D) Free-Standing Superhydrophilic Sponge.
abstract: A novel three-dimensional (3D) free-standing superhydrophilic sponge for industrial wastewater treatment was formed by combining chitosan and linear polyacrylamide (PAM). When the chitosan-PAM sponge is immersed into an oil-in-water emulsion, the milky white emulsion containing surfactant turns clear and clarified. Demulsification efficiency, capacity, and recyclability of this positively charged chitosan-PAM sponge to oil-in-water emulsions stabilized by different types of surfactants including anionic, nonionic, and cationic surfactants, has been investigated for further practical evaluation. A "breathing demulsification" mechanism is presented to explain this attractive demulsified process. The effective contact area between emulsion and sponge is increased by the microcomposite and nanocomposite hierarchical structure of the chitosan-PAM free-standing sponge. Then, interfacial interactions, size effect, and strain act as the driving force for the demulsification of the emulsified droplets at the surface of the sponge.
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Liangxin
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Yuning
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Na
authors.initials: N
authors.lastname: Liu
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Yingze
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Lin
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Yen
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Department of Chemistry, Tsinghua University , Beijing, 100084, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Feng
keywords: absorption; composite materials; demulsification; extrusion; sponge; surfactant