Sustainable remediation of Cr(VI)-contaminated soil by soil washing and subsequent recovery of washing agents using biochar supported nanoscale zero-valent iron.

Soil contamination by Cr(VI) has attracted widespread attention globally in recent years, but it remains a significant challenge in developing an environmentally friendly and eco-sustainable technique for the disposal of Cr(VI)-contaminated soil. Herein, a sustainable cyclic soil washing system for Cr(VI)-polluted soil remediation and the recovery of washing agents using biochar supported nanoscale zero-valent iron (nZVI-BC) was established. Citric acid (CA) was initially screened to desorb Cr(VI) from contaminated soil, mobilizing Cr from the highly bioaccessible fractions.

Lanthanum and magnesium activated palygorskite for adsorption of phosphate in piggery wastewater.

Removing phosphate from wastewater can help alleviate eutrophication. Therefore, in this study, lanthanum and magnesium were loaded onto the thermally modified palygorskite (PAL) using a coprecipitation method, and a composite material was prepared for phosphate recovery. In the pH range of 2-7, the material can effectively adsorb the phosphate.

Degradation of Sulfonamides by UV/Electrochemical Oxidation and the Effects of Treated Effluents on the Bacterial Community in Surface Water.

This study evaluated the effects of ultraviolet (UV) photolysis combined with electrochemical oxidation on sulfonamides (SAs) as well as its treated effluent on the bacterial community in surface water. In terms of degradation rate, the best anode material for electrochemical oxidation was Ti/RuO-IrO, which had the highest degradation kinetic constant compared to Ti/TaO-IrO and Ti/Pt. Experiments showed the highest degradation rate of SAs at 8.

Phenanthrene decomposition in soil washing effluents using UVB activation of hydrogen peroxide and peroxydisulfate.

In this work, the decomposition of phenanthrene (PHE) in mimic and real soil washing (SW) effluents was investigated using UVB light assisted activation of hydrogen peroxide (HO) and peroxydisulfate (PDS) oxidation processes. The impact of oxidant concentration, initial pH, and coexisting inorganic anions (Cl, HCO and NO) on PHE removal was evaluated. PHE degradation efficiency under UVB irradiation followed the order of UVB/PDS > UVB/HO > UVB.

Remediation of Cu-phenanthrene co-contaminated soil by soil washing and subsequent photoelectrochemical process in presence of persulfate.

A promising technology was proposed for the remediation of Cu and phenanthrene (PHE) co-contaminated soil. Firstly, Cu and PHE were simultaneously removed from soil using an extraction agent containing ethylenediaminetetraacetic acid (EDTA) and Tween 80 (TW80). Specifically, Cu was mobilized by the chelation of EDTA while PHE was desorpted from soil by TW80 micelles.

Phenanthrene degradation using Fe(III)-EDDS photoactivation under simulated solar light: A model for soil washing effluent treatment.

In this work, for the first time, the nonionic surfactant polyoxyethylene-(20)-sorbitan monooleate (Tween 80, CHO) aided soil washing effluent was treated by enhanced activation of persulfate (PS) using Fe(III)-EDDS (EDDS: ethylenediamine-N, N-disuccinic acid) complexes under simulated solar light irradiation. The performance of this system was followed via the production and reactivity of radical species (SO, HO, Cl) and degradation of phenanthrene (PHE) used as a model pollutant in soils. Different physico-chemical parameters such as the concentration of reactive species and pH were investigated through the PHE degradation efficiency.

Selective adsorption of phenanthrene dissolved in Tween 80 solution using activated carbon derived from walnut shells.

In order to remove phenanthrene (PHE) from surfactant solution, activated carbon (AC) was prepared from waste walnut shells and characterized by Brunauer-Emmett-Teller (BET), field-emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). For solutions containing PHE and Tween 80, the former was effectively removed and the latter could be economically recovered after adsorption by the prepared AC. The π-π interactions and oxygen containing functional groups of AC play important roles in the PHE adsorption process.