Synthesis of High Specific Surface Lithium-Ion Sieve Templated by Bacterial Cellulose for Selective Adsorption of Li+

Abstract

In recent years, with the development of batteries, ceramics, glass and other industries, the demand for lithium has increased rapidly. Due to the rich lithium resources in seawater and salt-lake brine, the question of how to selectively adsorb and separate lithium ions from such brine has attracted the attention and research of many scholars. The Li-ion sieve stands out from other methods thanks to its excellent special adsorption and separation performance. In this paper, mesoporous titanium dioxide and lithium hydroxide were prepared by hydrothermal reaction using bacterial cellulose as a biological template. After calcination at 600 °C, spinel lithium titanium oxide Li2TiO3 was formed. The precursor was eluted with HCl eluent to obtain H2TiO3. The lithium titanate were characterized by IR, SEM and X-ray diffraction. The adsorption properties of H2TiO3 were studied by adsorption pH, adsorption kinetics, adsorption isotherm and competitive adsorption. The results show that H2TiO3 has a single-layer chemical adsorption process, and has a good adsorption effect on lithium ions at pH 11.0, with a maximum adsorption capacity of 35.45 mg g−1. The lithium-ion sieve can selectively adsorb Li+, and its partition coefficient is 2242.548 mL g−1. It can be predicted that the lithium-ion sieve prepared by biological template will have broad application prospects.

Granulation of Lithium-Ion Sieves Using Biopolymers: A Review

“…By contrast, Qian et al [69] applied a multi-step crosslinking strategy to afford multiple adsorption binding sites, as well as to enhance the mechanical stability of the produced granules. Zhang et al [70] reported the preparation of high-specific surface LISs templated by bacterial CLS for the selective adsorption of Li ions. The templated LISs were synthesized as follows: Bacterial CLS (B-CLS) hydrogel was added to deionized water for 15 min to enhance swelling, followed by freezing with liquid nitrogen and freeze-drying to obtain a B-CLS aerogel network structure.…”

Granulation of Lithium-Ion Sieves (LISs) Using Biopolymers: A Review

“…Contrary to several reports on the use of organic and inorganic materials as binders for the granulation of metal-based LISs, reports on the use of biopolymers as binders are limited in the open literature (cf. Figure 4) [24,[49][50][51][52][53][54][71][72][73][74][75][76][77][78][79]. Additionally, there are currently no review articles that highlight the available knowledge gaps on the use of biopolymers as binders for the granulation of LISs.…”

“…Additionally, there are currently no review articles that highlight the available knowledge gaps on the use of biopolymers as binders for the granulation of LISs. Most recent studies have focused on the use of chitosan, alginate, agar, and cellulose as binders to prepare granulated LISs [24,[49][50][51][52][53][54][71][72][73][74][75][76][77][78][79]. For instance, numerous studies [49][50][51][52][53] have reported on the use of chitosan in various forms (cross-linked and non-cross-linked) as binder for the granulation of LISs.…”

“…Adsorption studies with the LIS granules showed that optimum conditions for the uptake of Li ions by the granules were: pH 12 and 24 h equilibration time, where the uptake capacity was 12.02 mg/g. Desorption studies at variable concentrations of HCl as the eluent revealed that titanium loss increased with increasing Zhang et al [72] reported the preparation of high specific surface LISs templated by bacterial CLS for the selective adsorption of Li ions. The templated LISs were synthesized as follows: Bacterial CLS (B-CLS) hydrogel was added to deionized water for 15 minutes to enhance swelling, followed by freezing with liquid nitrogen and freeze-drying to obtain a B-CLS aerogel network structure.…”

“…The authors also reported that the B-CLS templated LISs display good selectivity for Li ions as well as strong regeneration ability, where the adsorption capacity remained above 82% of the initial value after 5 adsorption-desorption cycles, as shown in Figure 13. The synthetic strategy employed by Zhang et al [72] is similar to the study of Qian et al [71], where the notable difference between the two synthetic strategies relate to the use of an ionic liquid ([Bmim]Cl) for the dissolution of CLS by Qian et al [71]. In a separate study, Liu et al [73] reported on the preparation and characterization of LISs embedded in a hydroxyethyl CLS cryogel (LIS-HEC) for the continuous recovery of Li from brine.…”