Macroporous Lithium Adsorbent Monolith Prepared via High Internal Phase Emulsion Technique

Abstract

A facile strategy to fabricate macroporous polymeric foam composites with uniformly distributed lithium-ion sieves (LIS) was fabricated toward lithium ion (Li + ) selective recovery. With LiMn 2 O 4 nanoparticles as stabilizers, oil-in-water (o/w) high internal phase emulsions (HIPEs) were prepared, and then a series of porous hydrophilic materials containing LIS (LNP@polyHIPEs) was obtained by the polymerization of water-soluble monomers in the Pickering HIPEs and followed by acid pickling. Lithium-ion adsorption was conducted by flowing lab made seawater through a LIS@polyHIPEs monolith. The LIS@polyHIPE exhibited a high adsorption capacity (∼35.6 mg/g (LiMn 2 O 4 )) and fast adsorption kinetics (the equilibrium time was ∼3.0 h). The kinetics data and fitting them by a pseudo-first-order model showed that the loading of LIS onto polyHIPE had little influence on the adsorption rate, and the uptake of Li + onto LIS@polyHIPE was an ion exchange or chemical adsorption control process. After the Li + was extracted by washing the foam with a 0.5 mol/L HCl aqueous solution, the LIS@polyHIPE could be reused for recovery of Li + from seawater. Its adsorption capacity and Li + extraction rate were more than 31 mg/g (LiMn 2 O 4 ) and 90% in four cycles, respectively.

Preparation of a Porous Protein-Based Composite Material by In Situ Polymerization of Pickering High Internal Phase Emulsion for Adsorption of Lead Ions

“…However, these surfactants themselves are somewhat toxic and their removal requires a large amount of solvent for extraction, which limits their application in HIPE polymers. To stabilize HIPEs, researchers began testing solid inorganic nanoparticles made from nano-SiO 2 , 14 TiO 2 , 15 graphene oxide, 16 and Fe 3 O 4 ; 17 however, the inorganic nanoparticles often required modification, which can be a cumbersome operation. Therefore, it is of great importance and value to develop solid nanoparticle stabilizers for HIPEs that are environmentally friendly, are easy to apply, and have strong emulsion stability and good biocompatibility as templates to prepare porous adsorbent polymer materials with open pore structures.…”

Macroporous polyHIPE modified with β-cyclodextrin for the removal of bisphenol A from water

“…Macroporous polymeric monoliths are ideally suited for adsorption because of their large surface area, excellent flow and mass transport properties, and simple adsorption operation. [41][42][43][44][45][46] The use of a high-internal-phase emulsion (HIPE) represents a templating method to fabricate macroporous polymeric monoliths (termed as polyHIPEs) with an open-cellular structure, and have thus received increased attention. PolyHIPEs are usually fabricated by the polymerization of stable concentrated water-in-oil (w/o) HIPEs.…”

LIS-doped thin-film nanocomposite membrane adsorbent with low shielding effect for effective lithium recovery from geothermal water

“…These limitations have triggered research into combining powdery LIS with membrane technology to make mixed matrix membrane (MMM) adsorbents in the form of spheres, 13 foam, 14 sheets 15 and fibers, 16,17 where LIS as a dispersed phase fills the continuous phase of a polymer, such as polysulfone (PSF), polyacrylonitrile (PAN), or polyvinyl chloride (PVC), by non-solventinduced phase inversion, electrospinning and freeze-drying methods, respectively. Despite improvements in the fluidity and cyclability of MMMs, some challenges urgently need solving: (1) the severe decrease in Li + adsorption capacity and rate due to the shielded active adsorption sites of LIS by the polymer matrix; (2) the poor interfacial compatibility between inorganic LIS and organic polymer matrix caused by the lack of chemical bonds, which affects the structural stability and operational durability of MMMs.…”