Mesoporous silica nanoparticles for rapid removal of PFOA: Impact of surface functional groups on adsorption efficiency and adsorbent regeneration.

This study explores mesoporous silica nanoparticles (MSN) synthesized via oil-water biphase stratification and functionalized with n-octyltrichlorosilane (OTS), 3-aminopropyltriethoxysilane (APTES), or both, yielding OMSN, AMSN, and OAMSN. All adsorbents rapidly removed perfluorooctanoic acid (PFOA) from water, reaching 95 % adsorption equilibrium within 10 min. PFOA adsorption kinetics showed that OAMSN, with the largest pore size (14.

Towards a better understanding of sorption of persistent and mobile contaminants to activated carbon: Applying data analysis techniques with experimental datasets of limited size.

The complex sorption mechanisms of carbon adsorbents for the diverse group of persistent, mobile, and potentially toxic contaminants (PMs or PMTs) present significant challenges in understanding and predicting adsorption behavior. While the development of quantitative predictive tools for adsorbent design often relies on extensive training data, there is a notable lack of experimental sorption data for PMs accompanied by detailed sorbent characterization. Rather than focusing on predictive tool development, this study aims to elucidate the underlying mechanisms of sorption by applying data analysis methods to a high-quality dataset.

A Deep Insight into Perfluorooctanoic Acid Photodegradation Using Metal Ion-Exchanged Zeolites.

Treating perfluorooctanoic acid (PFOA) in an aqueous environment is problematic due to its low concentration and its high resistance to biological and chemical degradation. To tackle this challenge, combinations of pre-enrichment and photodegradation processes are promising solutions. In this work, we investigated metal ion-exchanged zeolites as adsorbents and photocatalysts for PFOA treatment.

Fe-zeolites for the adsorption and oxidative degradation of nitroaromatic compounds in water.

Nitroaromatic compounds (NACs) are prominent explosives. In this context, these toxic substances were released into the environment and cause long-lasting groundwater contamination. In preparation of a possible in-situ remediation, colloidal Fe-zeolites were investigated for their capabilities as adsorbents and oxidation catalysts.

Bottom-Up Synthesis of De-Functionalized and Dispersible Carbon Spheres as Colloidal Adsorbent.

Recent innovative adsorption technologies for water purification rely on micrometer-sized activated carbon (AC) for ultrafast adsorption or in situ remediation. In this study, the bottom-up synthesis of tailored activated carbon spheres (aCS) from sucrose as renewable feedstock is demonstrated. The synthesis is based on a hydrothermal carbonization step followed by a targeted thermal activation of the raw material.

Recent developments in microplastic contaminated water treatment: Progress and prospects of carbon-based two-dimensional materials for membranes separation.

Micro (nano)plastics pollution is a noxious menace not only for mankind but also for marine life, as removing microplastics (MPs) is challenging due to their physiochemical properties, composition, and response toward salinity and pH. This review provides a detailed assessment of the MPs pollution in different water types, environmental implications, and corresponding treatment strategies. With the advancement in nanotechnology, mitigation strategies for aqueous pollution are seen, especially due to the fabrication of nanosheets/membranes mostly utilized as a filtration process.

Uniform and dispersible carbonaceous microspheres as quasi-liquid sorbent.

Functional colloidal carbon materials find various applications, including the remediation of contaminated water and soil in so-called particle-based in-situ remediation processes. In this study, uniform and highly dispersible micro-sized carbonaceous spheres (CS) were generated by hydrothermal carbonization (HTC) of sucrose in the presence of carboxymethyl cellulose (CMC) as environmentally friendly polyelectrolyte stabilizer. In order to ensure their optimal subsurface delivery and formation of a self-contained treatment zone, a narrow size distribution and low agglomeration tendency of the particles is desired.

Phylogeny and potential virulence of cryptic clade species complex isolates derived from an arable field trial.

Analysis of taxonomy has expanded into a species-complex with the identification of divergent cryptic clades. A key question is the evolutionary trajectory of these clades and their relationship to isolates of clinical or veterinary importance. Since they have some environmental association, we screened a collection of isolated from a long-term spring barley field trial for their presence.

Borohydride and metallic copper as a robust dehalogenation system: Selectivity assessment and system optimization.

Hydrodechlorination (HDC) using noble-metal catalysts in the presence of H-donors is a promising tool for the treatment of water contaminated by halogenated organic compounds (HOCs). Cu is an attractive alternative catalyst to noble metals since it is cheaper than Pd, Rh, or Pt and more stable against deactivation. Cu with borohydride (BH) as reductant (copper-borohydride reduction system; CBRS) was applied here for the treatment of saturated aliphatic HOCs.

Genetic variability of Arthurdendyus triangulatus (Dendy, 1894), a non-native invasive land planarian.

Arthurdendyus triangulatus (Dendy, 1894) is a land planarian native to New Zealand which has become established in the United Kingdom and the Faroe Islands during the last 60 years. The species has become prevalent and widely established in Scotland mediated by human activity mostly through the exchange of plants and associated soil. As a predator of earthworms, concerns regarding both the direct impact on earthworm abundance and diversity and the indirect impact on those birds and mammals that have earthworms as a primary dietary component led to A.

Interaction of zero-valent iron and carbonaceous materials for reduction of DDT.

Dechlorination of dichlorodiphenyltrichloroethane (DDT) as a model compound was performed with zero-valent iron (micro-ZVI and nano-ZVI) as reductant and carbonaceous adsorbents as sink and catalyst in water. DDT is rapidly converted to dichlorodiphenyldichloroethane (DDD) in direct contact with ZVI. However, up to 90% of the DDD is transformed into non-identified, most likely oligomeric products.

In-situ treatment of herbicide-contaminated groundwater-Feasibility study for the cases atrazine and bromacil using two novel nanoremediation-type materials.

Two injectable reactive and sorption-active particle types were evaluated for their applicability in permeable reaction zones for in-situ removal of herbicides ("nanoremediation"). As model substances, atrazine and bromacil were used, two herbicides frequently occurring in groundwater. In order to provide recommendations for best use, particle performance was assessed regarding herbicide degradation and detoxification.

Environmental risk or benefit? Comprehensive risk assessment of groundwater treated with nano Fe-based Carbo-Iron®.

Groundwater is essential for the provision of drinking water in many areas around the world. The performance of the groundwater-bearing aquifer relies on the ecosystem services provided by groundwater-related organisms. Therefore, if remediation of contaminated groundwater is necessary, the remediation method has to be carefully selected to avoid risk-risk trade-offs that might impact these ecosystems.

Sulfidation of ZVI/AC composite leads to highly corrosion-resistant nanoremediation particles with extended life-time.

Nanoscale zero-valent iron (nZVI) is a powerful reductant for many water pollutants. The lifetime of nZVI in aqueous environments is one of its limitations. Sulfidation of the nZVI surface by reduced sulfur species is known to significantly modify the particle properties.

Acceleration of microiron-based dechlorination in water by contact with fibrous activated carbon.

Zero-valent iron (ZVI) is widely applied for reduction of chlorohydrocarbons in water. Since the dechlorination occurs at the iron surface, marked differences in rate constants are commonly found for nanoscale and microscale ZVI. It has already been shown for trichloroethene (TCE) adsorbed to activated carbon (AC) that the dechlorination reaction is shifted to the carbon surface simply by contacting the AC with highly reactive nanoscale ZVI particles.

Linkage Disequilibrium and Evaluation of Genome-Wide Association Mapping Models in Tetraploid Potato.

Genome-wide association studies (GWAS) have become a powerful tool for analyzing complex traits in crop plants. The current study evaluates the efficacy of various GWAS models and methods for elucidating population structure in potato. The presence of significant population structure can lead to detection of spurious marker-trait associations, as well as mask true ones.

Combined chemical and microbiological degradation of tetrachloroethene during the application of Carbo-Iron at a contaminated field site.

After the injection of Carbo-Iron® into an aquifer contaminated with tetrachloroethene (PCE), combined chemical and microbiological contaminant degradation processes were found in a long-term study of the field site in Lower Saxony (Germany). The applied composite material Carbo-Iron, which consists of colloidal activated carbon and embedded nanoscale zero-valent iron (ZVI) structures, functioned as intended: accumulating the pollutants and promoting their reductive dechlorination. Furthermore, the particles decreased the redox potential of the groundwater due to their reaction with oxygen and to the ZVI-corrosion-induced formation of molecular hydrogen up to 190 days after the injection, the latter promoting sulphate-reducing conditions.

Biological effects of four iron-containing nanoremediation materials on the green alga Chlamydomonas sp.

As nanoremediation strategies for in-situ groundwater treatment extend beyond nanoiron-based applications to adsorption and oxidation, ecotoxicological evaluations of newly developed materials are required. The biological effects of four new materials with different iron (Fe) speciations ([i] FerMEG12 - pristine flake-like milled Fe(0) nanoparticles (nZVI), [ii] Carbo-Iron - Fe(0)-nanoclusters containing activated carbon (AC) composite, [iii] Trap-Ox® Fe-BEA35 (Fe-zeolite) - Fe-doped zeolite, and [iv] Nano-Goethite - 'pure' FeOOH) were studied using the unicellular green alga Chlamydomonas sp. as a model test system.

Enhanced protection of PDMS-embedded palladium catalysts by co-embedding of sulphide-scavengers.

For Pd-containing hydrodechlorination catalysts, coating with poly(dimethyl siloxane) (PDMS) was proposed earlier as promising protection scheme against poisoning. The PDMS coating can effectively repel non-permeating poisons (such as SO) retaining the hydrodechlorination Pd activity. In the present study, the previously achieved protection efficiency was enhanced by incorporation of sulphide scavengers into the polymer.

Accelerated Catalytic Fenton Reaction with Traces of Iron: An Fe-Pd-Multicatalysis Approach.

An accelerated catalytic Fenton (ACF) reaction was developed based upon a multicatalysis approach, facilitating efficient contaminant oxidation at trace levels of dissolved iron. Beside the Fe(II)/H2O2 catalyst/oxidant pair for production of OH-radicals, the ACF system contains Pd/H2 as catalyst/reductant pair for fast reduction of Fe(III) back to Fe(II) which accelerates the Fenton cycle and leads to faster contaminant degradation. By this means, the concentration of the dissolved iron catalyst can be reduced to trace levels (1 mg L(-1)) below common discharge limits, thus eliminating the need for iron sludge removal, which is one of the major drawbacks of conventional Fenton processes.

Fluorescence labelling as tool for zeolite particle tracking in nanoremediation approaches.

Colloidal Fe-zeolites such as Fe-BEA-35 are currently under study as new adsorbent and catalyst materials for in-situ chemical oxidation with H2O2. As for nanoremediation in general, the availability of suitable particle detection methods is a requirement for successful process development and particle tracing. Detection and distinguishing between natural colloids and introduced particles with a similar composition are a challenge.

Carbo-Iron as improvement of the nanoiron technology: From laboratory design to the field test.

In a first pilot-scale field test the use of Carbo-Iron® was successfully demonstrated. Carbo-Iron was developed with the goal to overcome significant shortcomings of nanoscale zero-valent iron (NZVI) for in-situ groundwater remediation. The composite material of colloidal activated carbon and embedded nanoiron structures has been tested for the remediation of a tetrachloroethene (PCE) contaminated field site in Lower Saxony, Germany.

Colloidal activated carbon for in-situ groundwater remediation--Transport characteristics and adsorption of organic compounds in water-saturated sediment columns.

Colloidal activated carbon can be considered as a versatile adsorbent and carrier material for in-situ groundwater remediation. In analogy to other nanoremediation approaches, activated carbon colloids (ACC) can be injected into the subsurface as aqueous suspensions. Deposition of ACC on the sediment creates a sorption barrier against further spreading of hydrophobic pollutants.

Evolutionary Dynamics of the Cellulose Synthase Gene Superfamily in Grasses.

Phylogenetic analyses of cellulose synthase (CesA) and cellulose synthase-like (Csl) families from the cellulose synthase gene superfamily were used to reconstruct their evolutionary origins and selection histories. Counterintuitively, genes encoding primary cell wall CesAs have undergone extensive expansion and diversification following an ancestral duplication from a secondary cell wall-associated CesA. Selection pressure across entire CesA and Csl clades appears to be low, but this conceals considerable variation within individual clades.

Probing protein targeting to plasmodesmata using fluorescence recovery after photo-bleaching.

Fluorescence recovery after photo-bleaching (FRAP) involves the irreversible bleaching of a fluorescent protein within a specific area of the cell using a high-intensity laser. The recovery of fluorescence represents the movement of new protein into this area and can therefore be used to investigate factors involved in this movement. Here we describe a FRAP method to investigate the effect of a range of pharmacological agents on the targeting of Tobacco mosaic virus movement protein to plasmodesmata.