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Quantitatively simultaneous detection of hydroquinone (HQ) and catechol (CC) with low limit of detection (LOD) and wide detection range is of critical significance in water quality control but faces great challenges due to their isomer similarity and a large range of contamination concentrations. Herein, high density of boron atoms is introduced into nitrogen-doped nanocarbon (BNC) to realize simultaneous detection of HQ and CC with a large separation of peak potential (Δ E p) of 111 mV between oxidations of HQ and CC by differential pulse voltammetry. Besides, extremely low LODs of 33.3 and 16.3 nM for HQ and CC were achieved through amperometric I - t curve with wide linear ranges of 0.099 ∼ 43340 µM and 0.049 ∼ 5110 µM, respectively. The systematical investigation of the enhancement mechanism by spectroscopy and DFT calculations clearly reveal that the boron-nitrogen co-doping creates rich electroactive sites for high sensing performance toward HQ and CC, thereby shedding lights on the great effect of a unique nanostructure on electrocatalysis in sensing applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Strontium is one of the main radionuclide in wastewater from nuclear power plants. A new strongly acidic cation exchange resin of LewatitSM 1000KR was used to adsorb Sr2+, and the resin after adsorbing Sr2+ was volume-reduced and cured. The results showed that the maximum adsorption capacity of LewatitSM 1000KR resin for Sr2+ was 35.82 mg/mL at 308 K. The volume of the resin after adsorption of Sr2+ was reduced by 80% after calcination at 900 °C, while the content of Sr2+ in the resin was unchanged. This research provides a new idea for the solidification of radioactive strontium. [ABSTRACT FROM AUTHOR]

In this study, a new type of phosphorylated chitosan-supported nano iron (CSP/Fe0) composite material. CSP/Fe0 had a high adsorption rate (99.25%) and a maximum adsorption capacity (627.34 mg g−1) when the conditions were pH = 6, 308.15 K and 12 h. CSP/Fe0 had a specific surface area of CSP/Fe0 was 6.02 m2 g−1, and has a mesoporous structure with more active sites (average pore size is 9.67 nm). The primary mechanism may be the complexation of U(VI) with abundant –OH, –NH2, P=O on the surface of the material and the reduction of nanoscale zero-valent iron. Therefore, it is indicated that the material has good potential in remediation of uranium-contaminated groundwater environment. [ABSTRACT FROM AUTHOR]

A novel environmentally-friendly porous hydrogel adsorbent (GHPN) is firstly designed and prepared using dextran, phosphate, and calcium hydroxide for the adsorption of Be(II). GHPN shows good adsorption selectivity for Be(II) (K d = 1.53 × 104 mL/g). According the adsorption kinetics and thermodynamics, the theoretical adsorption capacity of GHPN to Be(II) is 43.75 mg/g (35 °C, pH = 6.5), indicating a spontaneous exothermic reaction. After being reused for 5 cycles, the adsorption and desorption efficiencies of Be(II) with GHPN are obtained to be more than 80 %, showing acceptable recycling performance. Both of the characterizations and theoretical calculations indicate that the phosphate group, hydroxyl group, and amino group own the affinity to form stable complexes with Be(II). Benefiting from the introduction of phosphate and amino, the adsorption effect of the hydrogel adsorbent on Be(II) can be greatly improved, and surface precipitation, complexation, and ligand exchange are the dominant mechanisms of beryllium adsorption. The results suggest that GHPN has great potential to be utilized as an eco-friendly and useful adsorbent of Be(II) from aqueous solution. [Display omitted] • A novel porous hydrogel GHPN was prepared to remove Be(II) from aqueous solution for the first time. • The maximum adsorption capacity of Be(II) by GHPN was up to 43.75 mg/g. • Surface precipitation, complexation, and ligand exchange were dominant for the adsorption of Be(II) by GHPN. [ABSTRACT FROM AUTHOR]

With the intensification of uranium-beryllium mining, a large amount of tailings wastewater is urgently needed to be treated. In this paper, the agricultural waste longan shell is used as the material (LSB), and the biochar with excellent pore structure is prepared by a straightforward high-temperature carbonization method. The primary adsorption mechanism may be ion exchange between beryllium and LSB. In addition, by characterizing the physical and chemical properties of LSB and adsorbed LSB (Used-LSB), it can be seen that the hydroxyl group on LSB forms a stable complex with beryllium and promotes the combination of carbonate group and beryllium.Graphical abstract: With the intensification of uranium-beryllium mining, a large amount of tailings wastewater is urgently needed to be treated. In this paper, the agricultural waste longan shell is used as the material (LSB), and the biochar with excellent pore structure is prepared by a straightforward high-temperature carbonization method. The primary adsorption mechanism may be ion exchange between beryllium and LSB. In addition, by characterizing the physical and chemical properties of LSB and adsorbed LSB (Used-LSB), it can be seen that the hydroxyl group on LSB forms a stable complex with beryllium and promotes the combination of carbonate group and beryllium. [ABSTRACT FROM AUTHOR]