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A new Ce(III) ion imprinted polymer (Ce(III)-IIP), which can be used for selective removal of Ce(III) from aqueous solutions, was successfully prepared based on the matrix material of ordered mesoporous silica SBA-15 by surface molecular imprinting technology. The prepared polymer was characterized by X-ray diffraction, transmission electron microscopy, Fourier transmission infrared spectrometry, and nitrogen adsorption−desorption isotherm. The results showed that Ce(III)-IIP kept a uniform framework mesoporosity of SBA-15 but a decrease in Brunauer−Emmett−Teller surface area, pore volume, and average pore diameter. Batch adsorption tests were researched on the effects of solution pH value, mass of sorbent, and contact time at different initial Ce(III) concentrations and temperatures. The kinetic data well fitted the pseudo-second-order kinetic model compared with the pseudo-first-order model. The adsorption isotherm fitted Langmuir model and the dimensionless separation factor RL indicated favorable adsorption. In addition, the Gibbs free energy (ΔG0), entropy (ΔS0), and enthalpy (ΔH0) were calculated from the adsorption data. These values suggested that the adsorption of Ce(III) onto Ce(III)-IIP was a spontaneous and endothermic nature of the process. The relative selectivity coefficients for different metal ion were larger than that of the nonimprinted polymer, indicating that Ce(III)-IIP synthesized for Ce(III) had a higher selectivity specialism for this ion.

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The application of biopolymers as eco-friendly stabilisers for strengthening soils has received increasing attention in recent years. This paper presents an experimental and numerical investigation of using xanthan gum, a green biopolymer, to stabilise mine tailings (MTs) for dust control. Impact tests that simulate the saltation process during wind erosion were carried out to evaluate the effect of xanthan gum on the impacting resistance of MTs, which is directly related to dust resistance. The impact test results show that the weight loss due to grain impacts is significantly reduced for biopolymer-treated MTs compared to that for untreated MTs, with more biopolymer leading to greater reduction. The improved dust resistance of MTs after biopolymer treatment may be attributed to the protective biopolymer coating formed at the surface of treated MTs, which imparts the MTs with a dense structure and enhanced cohesion and therefore improves the impacting resistance. Numerical simulation using the discrete element method was performed to explore the underlying mechanisms of how the biopolymer increases the dust resistance of MTs. The simulation results show that the bonding strength between MT particles increases linearly with biopolymer concentration; more biopolymer induces stronger interparticle bonding and therefore increases the impacting and cracking resistance of MTs.