The aging of polyethylene mulch films in the presence of cadmium.

To determine the fates of the persistent pollutants cadmium (Cd) and micro-plastics in agricultural soils, an in-depth understanding of the interactions between Cd and mulching film is required. In the present work, pot experiments are conducted under natural conditions to study the influence of various Cd concentrations on the aging process of polyethylene mulching film in soil collected from Changzhi, Shanxi Province. The results indicate that during 150 days, the aging degree of the mulch film increases gradually as the increased Cd concentration in the soil.

Effect of double carbon chains on enhanced removal of phenol from wastewater by amphoteric-gemini complex-modified bentonite.

A novle amphoteric-gemini complex-modified bentonite was prepared with a gemini surfactant ethylene bis (tetradecyl dimethyl ammonium chloride) (EB) on the basis of the bentonite modified by amphoteric modifier dodecyldimethyl betaine (BS). The surface and structural characteristics of modified bentonite were characterized by X-ray diffraction (XRD), specific surface area (S), scanning electron microscopy (SEM), Fourier infrared spectroscopy (FTIR), total carbon (TC) and total nitrogen (TN). In addition to studying the enhanced effect of gemini surfactants on phenol adsorption by kinetics and equilibrium adsorption, the influences of modification ratio, pH, temperature and ionic strength were investigated.

Insights into the interaction between cadmium/tetracycline and nano-TiO on a zeolite surface.

Titanium dioxide (TiO) nanoparticles interact with organic-inorganic pollutants in the environment, and these interactions affect their environmental behavior. The mechanisms of the interaction between TiO and organic-inorganic pollutants on the surface of clay minerals are still unclear. In this work, isotherm adsorption was studied to explore the interactions between Cd/tetracycline (TC), TiO nanoparticles, and a zeolite (Zeo).

Co-adsorption capabilities and mechanisms of bentonite enhanced sludge biochar for de-risking norfloxacin and Cu contaminated water.

Various bentonite-sludge biochar composites were fabricated by a sequence of loading and pyrolysis for the simultaneous removal of norfloxacin (NOR) and copper (Cu) from an aqueous solution. The morphology and characteristics of obtained composites were reflected through cation exchange capacity (CEC), BET specific surface area (S), SEM, XRD, FTIR and XPS. The isothermal adsorption results showed that Sips adsorption model fitted better for the adsorption of NOR and Cu during co-adsorption.

[Adsorption of BS-18 Amphoterically Modified Bentonite to Tetracycline and Norfloxacin Combined Pollutants].

Antibiotic pollution in the environment has become a hot topic. The amphoteric surfactant octadecyl dimethyl betaine (BS-18) was adopted to modify bentonite to investigate the effects and mechanisms of the composite adsorption of different types of antibiotics. Under the different modification ratios, temperatures, pH values, and ionic strength conditions, the adsorption of tetracycline (TC) and norfloxacin (NOR) by bentonite was studied under single and compound conditions, and the adsorption mechanism was analyzed and discussed in combination with the surface properties of amphoterically modified bentonite.

Co-existing TiO nanoparticles influencing adsorption/ desorption of tetracycline on magnetically modified kaolin.

Interaction of coexisting nanoparticles (NPs) and other pollutants may affect their behavior in the environment. In this study, we investigated the effects of TiO NPs on the adsorption and desorption of tetracycline (TC) by magnetized kaolin (MK). The interactions among TC, TiO NPs, and MK were then discussed through their morphology and characteristics by using scanning electron microscopy, X-ray energy dispersive spectrometry, Transmission electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy analyses.

[Adsorption and Interaction of Cu and Pb on BS-12 Amphoteric Modified Bentonites].

Amphoteric modification can simultaneously improve the adsorption of organic pollutants and heavy metals on clay minerals. Study of the adsorption and interaction of multiple heavy metals on amphoteric modified soils is therefore of practical significance. Here, bentonite-(CK) and 150BS-12-modified bentonites (150BS-12) were characterized both before and after metal ion adsorption using Fourier-transform infrared spectroscopy (FTIR).

Comparison of Cd adsorption onto amphoteric, amphoteric-cationic and amphoteric-anionic modified magnetic bentonites.

Organic-magnetic bentonites (OMBts), i.e., amphoteric modified MBt (BS-MBt), amphoteric-cationic modified MBt (BS-CT-MBt) and amphoteric-anionic modified MBt (BS-SDS-MBt), obtained by modifying magnetic bentonite (MBt) with amphoteric surfactant (BS), cationic surfactant (CT) and anionic surfactant (SDS) were investigated with the aim to remove cadmium (Cd).

Hydrogen and methane production by co-digesting liquid swine manure and brewery wastewater in a two-phase system.

Co-digesting liquid swine manure and brewery wastewater for hydrogen and methane production was studied using an integrated, two-phase system with different organic loading rates (OLR) under mesophilic conditions. The highest volumetric hydrogen and methane production rates achieved were 294.06 ± 3.

[Comparison of Amphoteric-Cationic and Amphoteric-Anionic Modified Magnetic Bentonites:Characterization and Sorption Capacity of Phenol].

Magnetic bentonite is modified by an amphoteric surfactant (dodecyl dimethyl betaine, BS-12), then modified by a cationic surfactant (Cetyl Trimethyl Ammonium Bromide, CTMAB) and anionic surfactant (Sodium lauryl sulfonate, SDS). Amphoteric-cationic modified magnetic bentonite (BS-CT-MBT) and amphoteric-anionic modified magnetic bentonite (BS-SDS-MBT) are obtained. Structural identification of the samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analyses (TG), Fourier transform infrared spectra (FTIR), and vibrating sample magnetometer (VSM).

[Application of Amphoteric-Cationic Combined Modification on Phenol Adsorption of Yellow Brown Soil].

Based on the best modification ration of adsorption of phenol on montmorillonite modified by a mixture of amphoteric modifier, dodecyl dimethyl betaine(BS-12), and cationic modifier, hexadecyltrimethyl ammonium bromide(CTMAB),an experiment was designed to prepare two series of amphoteric-cationic modified soils by two yellow brown soils with montmorillonite contents of 43% and 6%,respectively. The adsorption properties of phenol were studied, and the adsorption influence at different temperature, pH and ionic strength was also analyzed and moreover, the adsorption differences between co-modified montmorillonite and yellow brown soils and between two co-modified yellow brown soils were discussed by comparing with co-modified montmorillonite. The results showed that adsorption of yellow brown soils as well as co-modified montmorillonite on phenol increased with combined modification, adsorption capacity was in order of 215BS+215CT(215%BS-12+215%CTMAB) > 215CT(215%CTMAB) > 215BS(215%BS-12) > CK1(unmodified soil containing montmorillonite content of 43%),33BS+33CT(33%BS-12+33%CTMAB) > 33CT(33%CTMAB) > 33BS(33%BS-12) > CK2(unmodified soil with montmorillonite content of 6%) at 30℃.

[Effect of Adding Compound Adsorbent on Phenanthrene and Cr(Ⅵ) Absorption by Lou Soil].

To study the effect of the addition of compound adsorbent on the phenanthrene and Cr(Ⅵ) adsorption of Lou soil, biochar (made from corn stover) and B (Bentonite modified by BS-12, dodecyl dimethyl betaine with modified ratio of 200% CEC of Bentonite) were mixed at mass ratios of 1:2, 1:1 and 2:1 as the compound adsorbents (CS, CS and CS). Different amounts (2%, 5% and 10%) of these three compound adsorbents were added into Lou soil. Batch method was used to analyze the phenanthrene and Cr(Ⅵ) adsorption isotherms of different Lou samples, and compare the effect of environmental conditions such as pH value and temperature on the phenanthrene and Cr(Ⅵ) adsorption.

[Effect of SDS on the adsorption of Cd2+ onto amphoteric modified bentonites].

Under different modified ratios, temperatures, pH and ionic strengths, the effect of sodium dodecyl sulfonate (SDS) on the adsorption of Cd2+ onto bentonites which modified with amphoteric modifier dodecyl dimethyl betaine (BS-12) was studied by batch experiments, and the adsorption mechanism was also discussed. Results showed that the adsorption of Cd2+ on amphoteric bentonites can be enhanced significantly by SDS combined modification, Cd2+ adsorption decreases in the order: BS + 150SDS (BS-12 + 150% SDS) > BS + 100SDS (BS-12 + 100% SDS) > BS +50SDS(BS-12 + 50% SDS) > BS + 25SDS (BS-12 + 25% SDS) > BS (BS-12) > CK (unmodified soil). The adsorption isotherm can be described by the Langmuir equation.

Dispersive liquid-liquid microextraction for the determination of phenols by acetonitrile stacking coupled with sweeping-micellar electrokinetic chromatography with large-volume injection.

The current routes to couple dispersive liquid-liquid microextraction (DLLME) with capillary electrophoresis (CE) are evaporation of water immiscible extractants and backextraction of analytes. The former is not applicable to extractants with high boiling points, the latter being effective only for acidic or basic analytes, both of which limit the further application of DLLME-CE. In this study, with 1-octanol as a model DLLME extractant and six phenols as model analytes, a novel method based on acetonitrile stacking and sweeping is proposed to accomplish large-volume injection of 1-octanol diluted with a solvent-saline mixture before micellar electrokinetic chromatography.

[Adsorption of Cd2+ ions in aqueous by diamine-modified ordered mesoporous SBA-15 particles].

Highly ordered channel structure SBA-15 was widely concerned as new adsorbents in environmental protection, in order to increase its heavy metal ions adsorption ability from aqueous solution, the diamine -modified porous silicate SBA-15 was synthesized by a hydrothermal grafting method and characterized by TEM, X-ray diffraction, FTIR and N2 adsorption-desorption. The SBA-15 and modified SBA-15 samples were used as sorbents to adsorb Cd(II) ions from aqueous solution. The effect of experimental parameters, such as pH, contact time, sorbent dosage and temperature were examined, and the maximum adsorption amount was also calculated.

[Pollution levels of perfluorochemicals in chicken eggs and duck eggs from the markets in Beijing].

Pollution levels of perfluorochemicals in eggs purchased from the markets in Beijing had been investigated. The egg samples of chicken and duck were collected from the 59 stalls of 14 main eggs wholesale markets in Beijing, respectively. Systematic analyses were made for seventeen kinds of perfluorochemicals (11 perfluorinated carboxylates (PFCAs), 3 perfluorinated sulfonates (PFSAs), perfluorooctane sulfonamide (FOSA), 2-perfluorooctylethanoic acid (FOEA) and 2H-perfluoro-2-decenoic acid (FOUEA) by a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).

Preparation of polydopamine coated Fe₃O₄ nanoparticles and their application for enrichment of polycyclic aromatic hydrocarbons from environmental water samples.

Core/shell structured magnetic Fe3O4/polydopamine (Fe3O4/PDA) nanoparticles have been successfully synthesized and developed as a magnetic solid-phase extraction (SPE) adsorbent in dispersion mode for the determination of trace polycyclic aromatic hydrocarbons (PAHs) in environmental samples. The Fe3O4/PDA synthetic procedure is simple and involves no organic solvents. Only 20mg of Fe3O4/PDA adsorbents are required to extract PAHs from 500mL water samples.

[Synthesis of core/shell structured magnetic carbon nanoparticles and its adsorption ability to chlortetracycline in aquatic environment].

Magnetic carbon nanoparticles with core/shell structure (Fe3C/Fe@C) and large surface areas were synthesized via hydrothermal method followed with heat treatment under N2 atmosphere. The adsorbent has strongly magnetic cores and graphitized carbon shell. The removal efficiency of chlortetracycline (CTC) from aquatic environment by Fe3C/Fe@C was investigated.

Fast defluorination and removal of norfloxacin by alginate/Fe@Fe3O4 core/shell structured nanoparticles.

Alginate-Fe(2+)/Fe(3+) polymer coated Fe(3)O(4) magnetic nanoparticles (Fe(3)O(4)@ALG/Fe MNPs) with core/shell structure are prepared and used as heterogeneous Fenton nanocatalyst to degrade norfloxacin (NOF). The Fenton-like process based on Fe(3)O(4)@ALG/Fe shows much higher efficiency on NOF degradation. Compared with Fe(3)O(4) nanoparticle-H(2)O(2) system, NOF degradation in Fe(3)O(4)@AlG/Fe-H(2)O(2) system can be conducted in a wide pH range (pH 3.

[Degradation of norfloxacin by nano-Fe3O4/H2O2].

The degradation of norfloxacin in aquatic environment was studied in the presence of Fe3O4 nanoparticles and H2O2. The effects of solution pH, temperature, dose of catalysts and concentration of H2O2 on norfloxacin degradation were surveyed. The degradation behaviors of different substrates by nano-Fe3O4/H2O2 were investigated and the reaction mechanism of norfloxacin was discussed.

Easy synthesis of surface-tunable carbon-encapsulated magnetic nanoparticles: adsorbents for selective isolation and preconcentration of organic pollutants.

We have prepared core/shell structured carbon-encapsulated magnetic nanoparticles (CMNPs) with a simple method by using inorganic iron salt and glucose solution as precursor substance. The synthetic procedure does not require the use of organic solvents. We have utilized X-ray photoelectron spectroscopy, infrared spectroscopy, X-ray diffraction, and Raman analysis to examine the surface properties of CMNPs prepared at different temperature.

Strong adsorption of chlorotetracycline on magnetite nanoparticles.

In this work, environmentally friendly magnetite nanoparticles (Fe(3)O(4) MNPs) were used to adsorb chlorotetracycline (CTC) from aqueous media. Fe(3)O(4) MNPs exhibit ultrahigh adsorption ability to this widely used antibiotic. The adsorption behavior of CTC on Fe(3)O(4) MNPs fitted the pseudo-second-order kinetics model, and the adsorption equilibrium was achieved within 10h.

Humic acid coated Fe3O4 magnetic nanoparticles as highly efficient Fenton-like catalyst for complete mineralization of sulfathiazole.

Humic acid coated Fe(3)O(4) magnetic nanoparticles (Fe(3)O(4)/HA) were prepared for the removal of sulfathiazole from aqueous media. Fe(3)O(4)/HA exhibited high activity to produce hydroxyl (OH) radicals through catalytic decomposition of H(2)O(2). The degradation of sulfathiazole was strongly temperature-dependent and favored in acidic solution.

[Adsorption kinetics of phenol on organic modified Lou soil].

Using batch experiment, the adsorption kinetics of phenol on both tillage layer (TL) and clay layer (CL) of Lou soil modified with cetyltrimethylammonium bromide (CTMAB, CB) at various ratio (100 CB and 50 CB) and cetyltrimethylammonium bromide + sodium dodecylsulphonate (CTMAB + SDS, CS) mixture were carried out, and its mechanism was discussed also. The results showed that two adsorption velocity parameters of phenol, total-adsorption-velocity (Vt) and fast-adsorption-velocity (Vf), on both layers of modified soil are 2.64-3.