Ligand geometry matters: Comparative study of linear and annular chelating ligands in tailored magnetic chitosan for Cu(II) removal.

The chelation between metal ions and ligands is pivotal in defining the adsorption capacity and selectivity of Cu(II) adsorbents, particularly those based on chitosan (CS). However, the influence of the spatial geometric configuration of chelating ligands on Cu(II) chelation remains poorly understood. Here, we developed two amino ligand-modified CS-based adsorbents with distinct spatial ligand configurations-linear (DA-CS) and annular (MA-CS)-to elucidate their Cu(II) chelation mechanisms.

Advances in the Recovery of Critical Rare Dispersed Metals (Gallium, Germanium, Indium) from Urban Mineral Resources.

Urban mineral resources, with their significant recycling potential, have increasingly accumulated worldwide and become an important source for extracting valuable metals, particularly critical rare dispersed metals (CRDMs) such as gallium, germanium, and indium. As the electronics industry continues to grow rapidly, the demand for CRDMs is rising. However, CRDMs in primary mineral resources are often found in small, dispersed concentrations, making extraction challenging.

Selective adsorption of Ga(III) from aqueous solutions using magnetic chitosan-based ion-imprinted polymers: Synthesis optimization and mechanistic insights.

A magnetic chitosan-based ion-imprinted polymer (IIP) with high adsorption capacity, excellent selectivity for Ga(III), easy magnetic separation, and remarkable reusability was synthesized via a simple crosslinking polymerization. The IIP exhibited a Ga(III) adsorption capacity of 434.00 mg/g at pH 4, demonstrating high efficiency for Ga(III) removal from aqueous solutions.

Enhanced Gallium Extraction Using Silane-Modified Mesoporous Silica Synthesized from Coal Gasification Slag.

This study presents an innovative approach to utilize coal gasification coarse slag (CGCS) for efficient and low-cost gallium extraction. Using a one-step acid leaching process, mesoporous silica with a surface area of 258 m/g and a pore volume of 0.15 cm/g was synthesized.

Chitosan-induced self-assembly of montmorillonite nanosheets along the end-face for methylene blue removal from water.

In this study, chitosan-induced self-assembly of montmorillonite nanosheets (MMTNS) along the end-face to form the layered and porous structured composite with high adsorption capacity towards MB dye wastewater was investigated. The self-assembly process was driven by the hydrogen-bond interaction among -OH groups distributed along the end-face of MMTNS and -NH groups on chitosan (CS) chain, which finally formed the infinite two-dimensional lamellae. This technology remained the exposed adsorption sites on MMTNS surface, and solved the separation issue of spent MMTNS from water, making MMTNS/CS an excellent adsorption material for macromolecular MB dye.

Facile preparation of sulfhydryl modified montmorillonite nanosheets hydrogel and its enhancement for Pb(II) adsorption.

In the work, sulfhydryl functionalized montmorillonite nanosheets based hydrogel balls were firstly synthesized for Pb(II) adsorption, and then characterized by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), surface area analyzer (BET), thermogravimetry (TG), and zeta potential. Effects of initial solution pH, adsorbent dosage, contact time, temperature on Pb(II) adsorption of the resulting hydrogel balls were investigated systematically. The experimental results showed that the increase amount of sulfhydryl functionalized montmorillonite nanosheets (MMTNs-SH) maintained the hydrogel balls a better porous structure and bigger specific surface area, endowing it a bigger adsorption capacity.

Insight into the effect of oxidation degree of graphene oxides on their removal from wastewater via froth flotation.

The effect of oxidation degree of graphene oxides (GO) on their removal from wastewater via froth flotation was studied in this work. Four types of GO samples with different oxidation degrees were synthesized and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), atomic force spectroscopy (AFM) et al. The effects of cetyl trimethyl ammonium bromide (CTAB) concentration, pH, stirring time on the removal of GO by froth flotation had been discussed.

Study on the Interaction between Galena and Sphalerite During Grinding Based on the Migration of Surface Components.

In Pb-Zn ore flotation, unintentional activation of sphalerite often leads to difficult separation of Pb and Zn minerals, during which grinding plays a key role in unintentional activation. Therefore, the aim of this study was to evaluate the surface component changes of two different mineral particles and to propose the interaction between galena and sphalerite during mixed grinding using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results show that after mixed grinding of the galena and sphalerite, the Pb content on the sphalerite surface increased with the decrease of Zn and Fe contents on the sphalerite surface.

A review of the applications of ion floatation: wastewater treatment, mineral beneficiation and hydrometallurgy.

Ion flotation was originally used for pre-concentrating precious metals from dilute solutions. To date, it has attracted widespread attention in many fields due to its low energy requirements, simplicity, rapid operation, small space requirements, suitability for a variety of target ions at various levels, small volume of sludge, low residual concentration, and low operating cost. This review focuses on the applications of ion flotation in wastewater treatment, mineral beneficiation, such as rare precious metal recovery, and hydrometallurgy, such as pre-concentrating of rare earth elements and selective separation of multicomponent ions.