The objective of the present study was to investigate the transport and removal of Escherichia coli, Bacillus subtilis, Staphylococcus aureus, bacteriophage MS2, and bacteriophage Phix174 in the soils and pyrophyllite-amended soils. Laboratory columns experiments were performed under saturated flow conditions. Our results showed that bacteriophages passed through the soils more easily than bacteria under the given experimental conditions (pulse injection = 15 min, flow rate = 0.5 mL/min, column length = 20 cm, inner diameter = 2.5 cm, pH = 7.6, electrical conductivity (EC) = 150.1 μS/cm); the log removals of bacteria were in the range of 0.44 to 1.72, whereas the log removals of bacteriophages were between 0.01 and 0.13. Our results also demonstrated that the transport of bacteria and bacteriophages in the soil columns could be reduced considerably in the presence of pyrophyllite. Under the same column experimental conditions above, the log removals for MS2 and Phix174 in 50% soil + 50% pyrophyllite were 2.64 and 3.05, respectively, whereas the log removals in 100% pyrophyllite were 5.70 for MS2 and 5.10 for Phix174; those values were far greater than the log removals in 100% soil (MS2 = 0.063, Phix174 = 0.128). Additional column experiments (step injection, flow rate = 0.3 mL/min, column length = 30 cm, inner diameter = 2.5 cm, solution pH = 8.4, EC = 39.8 mS/cm) showed that the log removals for B. subtilis (1.72) and Phix174 (1.48) in the pyrophyllite were greater than those in the soil (B. subtilis = 1.41; Phix174 = 0.39). This study demonstrated that the pyrophyllite amendment method could be used for protecting groundwater from microbial contamination by animal carcass burial soils.

Heavy metals, chemical elements considered toxic at certain concentrations, can be considered potential threats to plants, animals, and biological resources of a particular ecosystem. Among them, mercury and aluminum, when involved in bioaccumulation processes, can cause damage to various organ systems of both animals and plants. In vegetables, heavy metals produce reactive oxygen species (ROS), which are involved in the occurrence of malformations and deficits in the growth of roodets and plumule of several species of plants, which justifies the study of natural antioxidant agents that may come to reverse or ameliorate the deleterious effects caused by these compounds. In this sense, this study aims to evaluate the cytoprotective effect of hydroethanolic extract of Stryphnodendron rotundifolium Mart., species popularly known as “barbatimão” against the heavy metals mercury and aluminum in vegetable model, because of its known antioxidant potential. To this end, there was the cytoprotection test in microbial and lettuce seeds (germination) in order to ascertain the potential of the said extract on the protection of roots and stem this. It was observed that the extract showed no allelopathic effect on lettuce seeds at a concentration of 32 μg/mL and in combination with HgCl₂ and AlCl₃, it enabled a higher growth in the roodets and stem Lactuta sativa L. These results demonstrated that the extract of Stryphnodendron rotundifolium can be an alternative to solve the problem with soil contamination by heavy metals, showing thus its promising potential cytoprotective in plant species.

In order to explore the synthesis of silicate-1 membrane on kaolin clay ceramic and the effect of Na⁺ ion substitution on the dielectric properties of ceramic, silicate-1@kaolin clay ceramics containing different content of Na⁺ were successfully synthesized by combining sintering, sol-gel, and ion exchange method. Samples were analyzed by chemical composition (XRF), X-ray diffraction (XRD), scanning electron microscope (SEM), digital hardness tester, and microwave dielectric measurement system. SEM images exhibited that a layer of silicate-1 was successfully grown on the surface of the kaolin clay ceramic. The energy dispersive spectrometer (EDS) revealed that the content of Na⁺ in silicate-1 decreased with increase of ion exchange time. The content of Na⁺ in silicate-1@kaolin clay ceramic decreased from 1.46 to 0.29% when the silicate-1@kaolin clay ceramic was treated by the unsaturated solution of NH₃ from zero to two times. In this process, the dielectric constant of the silicate-1@kaolin clay ceramic almost kept the same. But the dielectric loss of silicate-1@kaolin clay ceramic decreased from 0.474 to 0.131. Silicate-1@kaolin clay ceramic is expected to be used as sensor to detect some metal ions.

Copper/zinc bioaccumulation and the effect of phytotoxicity on the growth of lettuce (Lactuca sativa L.) were studied in plastic vessels containing (i) non-contaminated soil, (ii) copper-contaminated soils at concentrations of 75.0 and 125.0 mg kg⁻¹, (iii) zinc-contaminated soils at concentrations of 1200 and 2400 mg kg⁻¹, and (iv) soil enriched with swine manure. Copper and zinc concentrations in lettuce leaves were determined by flame atomic absorption spectrometry during 42 days of growth. Copper concentrations from 0.92 to 13.06 mg kg⁻¹ were found in lettuce leaves grown in copper-contaminated soils and zinc concentrations from 58.13 to 177.85 mg kg⁻¹ were found in lettuce leaves grown in zinc-contaminated soils. Copper and zinc concentrations in lettuce leaves grown in swine manure-enriched soils ranged from 0.82 to 8.33 and 0.68 to 13.27 mg kg⁻¹, respectively. Copper and zinc bioaccumulation caused a decrease in lettuce growth in metal-contaminated soils and an increase in phytotoxicity effects when compared to growth in non-contaminated and manure-enriched soils. These findings were confirmed by measuring leaf areas and biomasses. Copper was less toxic to lettuce than zinc due to the different concentrations in the soil. Lettuce growth and development was better in the swine manure-enriched soil than non-contaminated soil, which indicates that swine manure is a safe agricultural biofertilizer when used in appropriate amounts to avoid metal bioaccumulation in soil and plants.

In this study, the sorption characteristics of U(VI) onto eucalyptus biochar as a function of various operating parameters such as solution pH, initial metal ion concentration, contact time and ionic strength of the medium are reported. Biochar was characterised using various techniques such as CHNS element analysis, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). SEM analysis showed the presence of micro- and macropores in the sorbent, and FTIR spectra confirmed the presence of functional groups like carboxylic (−COOH), hydroxyls(−OH), carbonyls(–C=O), etc. Maximum sorption of about 95% is found to occur in the pH range of 5 to 6. U(VI) sorption onto biochar reached equilibrium within 20 min at pH 5.5. The kinetic data were analysed using both pseudo-first-order and pseudo-second-order kinetic models, and the latter is found to be more appropriate to explain the observed kinetics. The equilibrium data were correlated with Langmuir and Freundlich models, and the maximum monolayer adsorption capacity obtained from the Langmuir model was 27.2 mg/g at 293 K. From EDS, FTIR and XPS measurements, it is found that the sorption process involves chemical interaction between the U(VI) and the surface functional groups on the adsorbent. Efficient removal of low level of uranium from ammonium diuranate supernatant demonstrates its utility as sorbent for waste water treatment.

Phthalates are considered as dangerous priority pollutants, several effects being attributed to them: foetal deformations, cancers, and endocrine disruptions. Activated carbons are highly efficient materials for the adsorption of numerous organic molecules. Before their use, it is important first to determine both textural and chemical properties and to study kinetics and thermodynamics adsorption, to understand and to optimize the interactions between material and molecules. The aim of this work was to study the kinetics and the adsorption isotherms of three phthalates (dimethylphthalate, diethylphthalate, and diethylhexylphthalate) currently found in industrial effluents, on two different activated carbons. The co-adsorption of these molecules in a synthetic mix and in complex matrices was modeled. The kinetic study and adsorption isotherms of dimethylphthalate and diethylphthalate in monosolute and bisolute were first investigated, followed by a similar study with a mix of the three molecules in complex matrices (surface water (Loire and Loiret Rivers near Orléans city) and municipal wastewater treatment plant outflow). The pseudo-second-order kinetic model was used to determine the kinetic adsorption parameters. The Langmuir equation was used to calculate the surface occupied. Results showed that non-electrostatic interactions are predominant in phthalate adsorption in complex matrices, mainly due to dispersion forces and hydrophobic interactions.

The removal of Cu(II), Zn(II), Mn(II), and Fe(II)/Fe(III) from acid mine drainage by using coal bottom ash was investigated at pH 4.2. Metal ion sorption, measured as amount of metal ion sorbed per gram of coal bottom ash (mg/g), was strongly influenced by the L/S (liquid-to-solid ratio), contact time, and equilibrium metal ion concentration. Metal ion sorption increased with increasing contact time as well as the equilibrium metal ion concentration and eventually reached a steady value. Sorption of a particular metal ion from a multi-component solution onto coal bottom ash was always lower as compared to sorption from the single-component solution due to the effect of competing ions. Batch sorption of metal ions onto coal bottom ash followed pseudo-second-order kinetics, while the sorption isotherm followed the Langmuir isotherm model. Removal of metal ions from single- and multi-component metal ion solutions by coal bottom ash followed the sequence: Fe(II)/Fe(III) > Cu(II) > Mn(II) > Zn(II).

Ni, Cu, and Ni-Cu metal oxides supported on granular activated carbon (GAC) were synthesized and used in catalytic ozonation of heavy oil produced water. The effect of preparation conditions on their catalyst composition, catalyst structure, and catalytic activity was investigated. The catalyst structure was characterized by X-ray power diffraction (XRD). The results revealed that the Ni-Cu/GAC has the highest catalytic activity, followed by Cu/GAC and Ni/GAC. Metal oxide loading rate depended on impregnation process, whereas dispersion of metal oxides was controlled by calcination process. The XRD analysis showed that the principal active phase was Cu₂O for Cu/GAC and Ni-Cu/GAC catalyst and NiO for Ni/GAC catalyst. The most active plane was Cu₂O₍₂₀₀₎ and then followed by Cu₂O₍₁₁₀₎ and Cu₂O₍₁₁₁₎ for Cu-supported catalysts. Higher calcination temperature and time favored the generation of Cu₂O but increased the crystalline diameter. It also suggested that promoting the generation of NiO and Cu₂O phase and reducing the crystalline diameter could improve the catalytic activity. During Ni-Cu/GAC preparation, existence of Ni(NO₃)₂ could accelerate the adsorption of Cu(NO₃)₂, promoting the generation of Cu₂O, and improve the dispersion of Cu₂O phase. Graphical Abstract ᅟ

Bagasse activated carbon (AC) and the new type of activated carbon (KAC) prepared with reactivation method of ZnCl₂-KOH were modified with triethylenetetramine (TETA) and tetraethylenepentamine (TEPA). The as-modified adsorbents for CO₂ separation were investigated by thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), elemental analysis, N₂ adsorption–desorption, as well as scanning electron microscopy (SEM). When the content of amine group is 5%, the CO₂ adsorption quantity of TEPA-loaded adsorbents reaches the highest at 60 °C (3.62 mmol/g for KAC and 1.98 mmol/g for AC, respectively). With a more abundant pore structure, KAC is more suitable for amine modification and its adsorption capacity of CO₂ is higher than that of AC after amine modification. Cyclic adsorption–desorption tests showed satisfactory regenerations for the modified adsorbents. Compared with other adsorbents, such as activated carbon, microporous zeolite, and mesoporous molecular sieve reported in literature, the new adsorbent prepared from the by-product of sugar industry has good performance (1.05–3.14 mmol/g larger than those of others) under the same conditions (60 °C and 15% partial pressure). The results are expected to provide scientific basis for the practical application.

While governments and individuals strive to maintain the availability of high-quality water resources, many factors can “change the landscape” of water availability and quality, including drought, climate change, saltwater intrusion, aquifer depletion, population increases, and policy changes. Specialty crop producers, including nursery and greenhouse container operations, rely heavily on available high-quality water from surface and groundwater sources for crop production. Ideally, these growers should focus on increasing water application efficiency through proper construction and maintenance of irrigation systems, and timing of irrigation to minimize water and sediment runoff, which serve as the transport mechanism for agrichemical inputs and pathogens. Rainfall and irrigation runoff from specialty crop operations can contribute to impairment of groundwater and surface water resources both on-farm and into the surrounding environment. This review focuses on multiple facets of water use, reuse, and runoff in nursery and greenhouse production including current and future regulations, typical water contaminants in production runoff and available remediation technologies, and minimizing water loss and runoff (both on-site and off-site). Water filtration and treatment for the removal of sediment, pathogens, and agrichemicals are discussed, highlighting not only existing understanding but also knowledge gaps. Container-grown crop producers can either adopt research-based best management practices proactively to minimize the economic and environmental risk of limited access to high-quality water, be required to change by external factors such as regulations and fines, or adapt production practices over time as a result of changing climate conditions.