Nanoscaled Bi₂O₃ particles coated on ZnO nanorods (ZNRs) have been fabricated by combining hydrothermal technique with a chemical precipitation method. X-ray diffraction, field emission-scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and UV–vis absorption and photoluminescence studies were adapted to characterize the structure, morphologies, and optical properties of the nanocomposites. The results indicated that small Bi₂O₃ nanoparticles were well distributed on the surfaces of ZNRs. And the Bi₂O₃–ZNR nanocomposites showed high charge separation efficiency and •OH generation ability as evidenced by photoluminescence spectra. Under irradiation of a 55-W compact fluorescent lamp, the Bi₂O₃–ZNR nanocomposites demonstrated photocatalytic activities higher than pure ZNRs in the degradation of two endocrine-disrupting chemicals, phenol and methylparaben, which might be attributed to the high separation efficiency of photogenerated electron–hole pairs based on the cooperative role of Bi₂O₃ loading on ZNRs. Moreover, the Bi₂O₃–ZNR nanocomposite could be easily recovered and reused due to their one-dimensional nanostructural property. All these characteristics brought enormous benefits of Bi₂O₃–ZNR nanocomposites to the practical application in indoor environmental remediation.

Soils polluted by metals and organic compounds are a major challenge in soil remediation and environmental recovery; however, the technology to efficiently decontaminate soils polluted by both metal and organic pollutants does not yet exist. Most of these soils are disposed of in landfills. This study first evaluates chemical reagents (hydrochloric, nitric, sulfuric and lactic acids and ethanol) for leaching metals from soil. Assays were then conducted to evaluate non-ionic, ionic and amphoteric surfactants for pentachlorophenol (PCP) removal by flotation. Finally, a laboratory-scale leaching/flotation process was applied to treat four soil samples polluted with both organic ([PCP]ᵢ = 2.5–30 mg kg⁻¹) and metals ([As]ᵢ = 50–250 mg kg⁻¹, [Cr]ᵢ = 35–220 mg kg⁻¹, [Cu]ᵢ = 80–350 mg kg⁻¹) compounds. The organic compounds and metals are concentrated in the froth and liquid fractions, respectively. Removal yields of 82–93 %, 30–80 %, 79–90 % and 36–78 % were obtained from As, Cr, Cu and PCP, respectively, under optimized process conditions (H₂SO₄ = 1 N, [cocamidopropyl betaine]ᵢ = 1 % (w w⁻¹), t = 60 min, T = 60 °C, PD = 10 % (w v⁻¹)). The treatment of the produced leachate was also tested by chemical precipitation using different reagents.