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Sulfur nanoparticles (SNPs) have shown good potential in numerous fields due to their unique composition and properties. However, the direct utilization of abundant and inexpensive elemental sulfur for the large‐scale fabrication of high‐quality SNPs is still in its infancy. Herein, a simple one‐pot approach for the preparation of SNPs is presented, and gram‐scale SNPs can be readily prepared in one batch in the laboratory. By adding elemental sulfur‐ethylenediamine precursor to the acidic chitosan (CS) solution, chitosan‐capped sulfur nanoparticles (CS‐SNPs) can be formed immediately. Benefiting from the capping of CS, CS‐SNPs simultaneously possess small and uniform size with an average diameter of 19 nm, good aqueous dispersibility and stability, and favorable antioxidant capability against 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) free radicals. Moreover, CS‐SNPs also exhibit fine antibacterial activity against Staphylococcus aureus, and the minimum and optimal inhibitory concentrations are 256 and 512 µg mL−1, respectively. Considering the easy fabrication process and attractive attributes of CS‐SNPs, this investigation not only offers an effective method for the scalable fabrication of robust SNPs but also provides a feasible way for the value‐added utilization of elemental sulfur.

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Activated carbon (AC) has been widely utilized for the adsorption of pollutants from water. However, it is difficult to recycle the AC after adsorption. In this paper, we report a facile one-pot approach to fabricate magnetic poly(vinyl alcohol)/AC composite gel (mPVA/AC CG) by dropwise addition of an aqueous mixture of PVA, AC and iron ions into the ammonia solution. The obtained mPVA/AC CG after freeze-drying shows porous microstructure and favorable magnetic properties. The utilization of mPVA/AC CG for adsorptive removal of methylene blue (MB) and methyl orange (MO) dyes from water was investigated. The mPVA/AC CG not only exhibited good adsorption performance for both MB and MO dyes but also could be readily recycled using a magnet after adsorption. The adsorption process was well described by the pseudo-second-order kinetic model and the Langmuir isotherm model. Considering the simple fabrication process, good adsorption performance and favorable magnetic separation capability, this work provides a viable strategy for combining the features of AC and magnetic gel for fabrication of applicable magnetic adsorbent.

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Thallium is an extremely toxic metal and abundant in industrial wastewater but little studied. In order to understand the optimal adsorption kinetic parameters of the chelating resin containing hydrazine wastewater, we carried out adsorption experiments on the cerium-containing wastewater treated by chemical precipitation. In this chapter, the optimum adsorption conditions, adsorption model, dynamic adsorption curve and desorption and regeneration of adsorbent were determined at different pH, temperature, adsorption time and different adsorbent dosage. The results show that the removal rate of thallium wastewater by resin is up to 97.5% when the pH value is 9. The optimum adsorption temperature is 30 and the adsorption reached equilibrium at 80 min. The adsorption process is consistent with Lagergren quasi-second-order adsorption and Langmuir isotherm model. The regenerative properties of the resin show that the resin adsorption rates still reach 95.8% after repeat use for six times. In summary, the chelating resin has good adsorption and reusability to the thallium-containing wastewater