A simple procedure at room temperature using non-toxic and cost-effective precursors has been developed to prepare magnetic Prussian blue/graphene oxide (PB/Fe₃O₄/GO) nanocomposites for the removal of radioactive cesium in water. Taking advantage of the combined benefits of GO and magnetic PB nanoparticles, PB/Fe₃O₄/GO nanocomposites exhibit excellent removal efficiency (over 90% for 50 ppm Cs⁺) and rapid separation from an aqueous solution by an external magnetic field. In addition, the adsorption behavior of these adsorbents fits well with the Langmuir isotherm and the pseudo-second-order kinetic model. Sorption of 70.25% Cs⁺ to PB/Fe₃O₄/GO was finished in less than 30 min, and the maximum adsorption capacity was 55.56 mg g⁻¹. The improved adsorption efficiency and capacity of PB/Fe₃O₄/GO can be attributed to the anchoring technology, which reduced the aggregation of nanoparticles and increased the effective adsorption surface of the adsorbent. These nanocomposites present a high selectivity to Cs⁺ and extract it in trace amounts. The removal mechanism of Cs⁺ was revealed for the first time to be H⁺-exchange and/or ion trapping. The temperature and pH value both affect the sorption performance. The composites were stable in natural water, seawater, and acidic/basic solutions ranging from pH = 4 (HNO₃) to 10 (NaOH) with negligible leaching of Fe.

The Yellow River Delta (YRD) is a typical agricultural and petrochemical industrial area of China. To assess the current status of phthalate esters (PAEs) of soil residues, soil samples (0∼20 cm) (n = 82) were collected in Bincheng District, at the geographic center of the YRD. PAEs were detected in all topsoil samples analyzed, which indicated that PAEs are ubiquitous environmental contaminants. Concentrations of 11 PAEs are in the range of 0.794∼19.504 μg g⁻¹, with an average value of 2.975 μg g⁻¹. It was presented that PAEs pollution in this area was weak and monotonously increasing along the rural–urban gradient. Higher concentrations were observed from roadsides (and/or gutters), densely anthropogenic activities areas (such as the urbanization and industrialization), and agriculture influence district, which mainly originated from construction waste, municipal sewage, agricultural waste and pesticide, discarded plastic effusion and atmospheric depositions. Concentrations of PAEs were weakly positivity correlated with soil organic carbon content and pH, which suggested both of them can affect the distribution of PAEs. The concentration of di (2-ethylhexyl) phthalate and di-n-butyl phthalate dominated in the 11 PAEs, with the average values of 0.735 and 1.915 μg g⁻¹, respectively, and accounted for 92.1 % of the whole PAEs’ concentrations. No significant differences of PAE congeneric profiles were observed between our work and others previously reported, which is consistent with the use of similar commercial PAEs around the world.