Sorption capacity of seaweed-like sodium titanate mats for Co²⁺ removal

Abstract

The seaweed-like sodium titanate mat has a high Co2+ sorption capacity via the ion-exchange reaction due to its crystal structure, low crystallinity, and morphology.

Sr2+ sorption property of seaweed-like sodium titanate mats: effects of crystallographic properties

“…Recently, we reported the synthesis of a unique seaweed-like sodium titanate mat (SST), which is composed of randomly distributed layered-sodium titanate nanofibers, using a template-free alkaline hydrothermal process. 36 The SST showed a high Co 2+ sorption capacity by ion-exchange reactions without self-precipitation of cobalt hydroxide in comparison with commercially available Na 2 Ti 3 O 7 . Although this previous study underscores the importance of understanding the reaction mechanism of cation removal on the functionalisation of sorbents, the synthesis conditions, such as the effect of the alkaline concentration on crystallographic properties of the SST, have not been sufficiently discussed.…”

“…[26][27][28] The SST, i.e., T10M, was the dititanate phase, similar to that investigated in a report. 36 In contrast, the sodium trititanate structure (T15M), as the second group, exhibited a zigzag layered structure comprising three units of TiO 6 octahedra and an M + interlayer. 14,27,32,43 Na + in the trititanate phase (T15M) existed at two different sites: edge sites and layer sites.…”

“…The differences in the ionic radii, valency, hardness of the coexisting ions, and the solubility product of their precipitates are expected to affect the sorption properties of sodium titanate. 31,36 Therefore, the effects of coexisting ions on the adsorption capacity of SST in wastewater need to be investigated further under model conditions. However, our basic ndings will contribute to the development of SSTs as highly efficient puri-cation materials for water treatment.…”

“…Although this previous study underscores the importance of understanding the reaction mechanism of cation removal on the functionalisation of sorbents, the synthesis conditions, such as the effect of the alkaline concentration on crystallographic properties of the SST, have not been sufficiently discussed. 36 Alkaline concentration (Na + ) and solution pH are important factors for the formation of sodium titanate, 26 and therefore, optimisation of the material structure synthesis process is indispensable for improving its properties.…”

Upcycling discarded cellulosic surgical masks into catalytically active freestanding materials

“…In a similar fashion, it enables water disinfection through the degradation of pathogens such as bacteria or viruses (Foster et al 2011 ; Zhu et al 2018 ; Rodríguez-González et al 2020 ). In comparison with other methods such as adsorption (Xia et al 2020 ), filtration (Kondo et al 2020 ), or reverse osmosis (Liu et al 2015 ), photocatalyst particles can be reused with no need for reactivation and can be used under sun illumination to reduce the energetic cost. Originating from the inherent photocatalytic activity of titanium dioxide (TiO 2 ) (Khin et al 2012 ), the immobilization TiO 2 nanoparticles onto a mechanically flexible solid support such as surgical masks enables a self-standing hybrid capable of catalyzing a large range of reactions when excited with external radiation.…”