The storage of coal combustion residue (CCR) in surface water impoundments may have an impact on nearby water quality and aquatic ecosystems. CCR contains leachable trace elements that can enter nearby waters through spills and monitored discharge. It is important, therefore, to understand their environmental fate in affected systems. This experiment examined trace element leachability into freshwater from fly ash (FA), the most common form of CCR. The effects on water quality of FA derived from both high and low sulfur coal sources as well as the influences of two different emergent macrophytes, Juncus effusus and Eleocharis quadrangulata, were evaluated in wetland microcosms. FA leachate dosings increased water electric conductivity (EC), altered pH, and, most notably, elevated the concentrations of boron (B), molybdenum (Mo), and manganese (Mn). The presence of either macrophyte species helped reduce elevated EC, and B, Mo, and Mn concentrations over time, relative to microcosms containing no plants. B and Mo appeared to bioaccumulate in the plant tissue from the water when elevated by FA dosing, while Mn was not higher in plants dosed with FA leachates. The results of this study indicate that emergent macrophytes could help ameliorate downstream water contamination from CCR storage facilities and could potentially be utilized in wetland filtration systems to treat CCR wastewater before discharge. Additionally, measuring elevated B and Mo in aquatic plants may have potential as a monitoring tool for downstream CCR contamination.

A method for simultaneously determining the levels of aniline, benzidine, microcystin variants (microcystin-LR, RR, and YR) and carbaryl in water was developed based on ultra-performance liquid chromatography–electrospray ionization tandem mass spectrometry (UPLC-MS/MS). The chromatographic conditions were optimized for the trace determination. Without sample enrichment, the method detection limit for all test compounds ranged from 0.040 to 0.155 μg/L; meanwhile, the recoveries for all test compounds were 83.1–114%. Precision, indicated by the relative standard deviation, was <12.9%. The results meet the requirements for the determination of these compounds. Without the need to clean up the samples, the results of the analysis of samples from wastewater and surface water demonstrated that the UPLC-MS/MS method has the capability to analyze complex matrices in the trace-level monitoring of wastewater samples.

The purpose of this research was to evaluate the biodegradation extent of petroleum hydrocarbons by Phormidium ambiguum strain TISTR 8296 in the presence of inorganic nutrients and heavy metals as co-contaminants. In this context, waste motor oil served as a source of petroleum hydrocarbons. Strain TISTR 8296 grew actively with waste motor oil at 0.5–2.0% (v/v) concentrations and also exhibited good biodegradation potential at this concentration range. Meanwhile, its growth and biodegradation capacity fell down with increasing oil concentration to 3.0 and 4.0%. Strain TISTR 8296 adapted quickly to pH changes, showing good growth ability and biodegradation capability at a pH range of 4.0–9.0 with an acidic pH of 4.0 and 5.0 appearing to decelerate its biodegradation efficiency. The addition of PO₄ ³⁻ and NO₃ ⁻ exerted a strong stimulatory effect on growth and biodegradation efficiency, while a slight promoting effect was observed for NO₂ ⁻. By contrast, amendment of NH₄ ⁺ as well as heavy metals caused a substantial inhibitory effect on growth and biodegradation efficiency with NH₄ ⁺ and Mn(II) appearing to show a weak suppressing effect. GC-MS analyses indicated that strain TISTR 8296 could transform and degrade both aliphatic and aromatic compounds.

Natural zeolite clinoptilolite and synthetic zeolite Na-A were characterized using XRD and SEM to be used as adsorbents for ammonia from aqueous solutions, ground water, and sewage water. Clinoptilolite was mechanically activated for 2, 4, 6, and 8 h to study the effect of activation in enhancing the adsorption capacity. The adsorption by activated natural zeolite and synthetic zeolite is high pH dependent and achieve the best values at pH = 7. The adsorption capacity of activated natural zeolite increases with increasing the activation from 2 to 8 h achieving removal percentage close to that obtained using synthetic zeolite. The equilibrium was obtained after 60 min for synthetic zeolite and all the activated natural zeolite (except 2-h-activated product, the equilibrium was achieved after 30 min). The kinetic studies reflected the high fitness of the adsorption results of activated natural zeolite products and synthetic zeolite with pseudo-second-order model rather than the other kinetic models. The obtained isotherms reflected the formation of S-type isotherm curve for the adsorption using mechanically activated clinoptilolite and L-type curve for the uptake using synthetic zeolite. The results represented well with Langmuir model followed by Temkin and Freundlich model for adsorption using synthetic zeolite. The uptake using mechanically activated clinoptilolite can be represented by Temkin model rather than both Langmuir and Freundlich models. Thermodynamic parameters indicate spontaneous endothermic adsorption of ammonia using all the zeolitic products under investigation. Finally, the mechanically activated natural zeolite and synthetic zeolite exhibit high efficiency in the removal of ammonia and other water pollutants from ground water and sewage water.

Phosphate discharged in agricultural drainage causes water quality degradation on local, regional, and national scales. Iron oxyhydroxide filter materials can potentially remove the soluble phosphate present in drainage waters. Laboratory saturated column experiments and preliminary small-scale field tests were carried out to evaluate the effectiveness and efficiency of a synthetic goethite iron oxyhydroxide (α-FeOOH) filter material for phosphate treatment. Original iron oxyhydroxide filter material (SG-IOH-O) and the same filter material regenerated with sodium hydroxide (SG-IOH-R) were assessed. Results of replicated laboratory experiments showed that columns packed with SG-IOH-O or SG-IOH-R almost totally removed phosphate (>98%) from drainage waters spiked with an additional 1 or 10 ppm phosphate-P (PO₄-P). The column experiments with SG-IOH-O or SG-IOH-R additionally indicated that contact times of only 10 to 15 s were sufficient for near complete removal of phosphate from drainage water spiked with 1 ppm PO₄-P. In an initial small-scale filter treatment system field test with SG-IOH-O, percent phosphate removal averaged 89% in the first 200 days, which then decreased to an average 40% phosphate removal in the last 80 days. Following this initial field test, two field tests, one with SG-IOH-O and the other with SG-IOH-R, were conducted concurrently over a period of 193 days, with the SG-IOH-O system phosphate removal averaging 75%, while the SG-IOH-R system phosphate removal averaged 34%. This study’s findings support possible goethite iron oxyhydroxide filter material use for drainage water phosphate treatment; however, larger-scale field investigations are needed, particularly with modified regeneration procedures.

Understanding the sorption behavior of mixtures of pharmaceuticals is critical for predicting their environmental behavior and for risk assessment. Experiments on ketoprofen (KTP) and triclosan (TCS) sorption by wheat straw-derived biochars at 300 °C (WS300) and 700 °C (WS700) in single solute and bisolute systems were conducted to probe the sorption mechanisms. The results of the single solute sorption indicated that WS700 with higher degree of carbonization had higher sorption coefficient (K d) and nonlinearity than WS300. In a bisolute system, no competitive effect was observed for partition of neutral KTP and TCS in the noncarbonized phase of WS300, but they competed for the adsorptive sites on the carbonized phase of WS300 and WS700 for sorption, in which π-π interaction is proposed as the main mechanism. The competition in the bisolute system varied with degree of dissociation of KTP and TCS, and led to a lower and less nonlinear sorption compared with that in the single solute system. TCS was more competitive than KTP due to its higher hydrophobicity, and sorption inhibition of KTP was enhanced with increasing TCS concentration. Degree of both molecular dissociation and sorbent carbonization should be considered in bisolute sorption of organic pollutants by biochars.

Volatile organic compounds (VOCs) cause global and local impacts, resulting in environmental, health, and economic adverse effects. Industrial and waste management activities are the main anthropogenic stationary sources of VOCs in the atmosphere. The traditional technologies for the treatment of VOC-contaminated air present several limitations when treating effluents with low VOC concentrations, high airflow rate, and with compounds with low solubility in water. However, a novel technology, based on non-thermal plasmas (NTPs) and catalysis, has shown promising results in air purification. In this framework, after an initial overview on NTP-catalysis principles, this review presents and discusses 20 recent papers, with a threefold purpose: evaluating the most recent applications of NTP and NTP-catalysis reactors to the treatment of air-VOC mixtures, analyzing all the parameters that may influence the abatement efficiency and the by-product formation, and providing the reader with insights into the choice of the preferable configurations to use, based on the effluent type and the destination of the treated air. As a result of this review, NTPs may represent a promising option for indoor air treatment, especially because of the lower expected byproduct formation when treating low-concentrated VOC mixtures with relatively low air flow rates. If the target is the abatement of higher VOC concentrations, the higher energy efficiency obtainable in such conditions makes NTP-catalysis a cost-effective option for industrial applications. In addition, the formation of simpler and more soluble by-products makes NTPs a suitable technology for air pretreatment upstream of water-based removal technologies, such as absorption columns and biofilters.

Determination of hexavalent chromium (Cr (VI)) in tannery effluent is an important analytical objective for environmental monitoring and assessment. Here, a simple, accurate, and sensitive automated flow injection analysis (FIA) method is proposed in this paper. The procedure is based on a highly selective reaction between Ponceau S and Cr (VI) under acidic condition. The absorbance of the complex compounds was measured using an optical detector at 505 nm. The chemical factors and FIA variables that affect the system were fully discussed and optimized via univariate experimental design. Under the optimal conditions, a linear dynamic range of 0.1–3.0 mg/L with a satisfactory determination coefficient (R ²) of 0.9996 was obtained. The detection limit and relative standard deviation were 0.08 mg/L and 2.27%, respectively. Finally, the method was successfully applied to determine Cr (VI) in field samples of tannery effluent and the results have no significant difference comparing with one official method, indicating this FIA method could be practically promising for determination of Cr (VI) in tannery effluent.

The microbial diversity from a fluidized bed reactor (FBR) for nonionic surfactant linear alcohol ethoxylate (LAE – Genapol® C100) degradation was determined by 454-pyrosequencing analysis. The FBR was operated with a hydraulic retention time of 18 h for 163 days and fed with synthetic substrate supplemented with yeast extract and LAE. The system was operated in two stages: (I) 80 mg/L of sucrose in synthetic substrate plus 107.4 ± 47.3 mg/L LAE and (II) synthetic substrate without sucrose and 97.9 ± 37.7 mg/L of LAE. By using 454 pyrosequencing, 14,325 sequences with an average length of 225 bp were generated. Proteobacteria phyla predominated in support material (sand) biofilm, while for the biomass from the phase separator, there was a prevalence of Acidobacteria phyla. Furthermore, many reads were related to genera of degraders of LAE and other nonionic surfactants (Desulfosporomusa, Syntrophomonas, Desulfobulbus, Geobacter, Dongia, etc.). Higher diversity and equitability indices were obtained for the biomass from the phase separator. The use of sucrose (C₁₂H₂₂O₁₁) as co-substrate for LAE degradation favored the microbial diversity in the support material and in the phase separator, indicated by the Shannon-Wiener (H′) index. The removal of sucrose from the synthetic substrate definitely altered the microbial community but did not influence the LAE efficiency removal.

Herbicide-tolerant (HT) crops such as those tolerant to glyphosate simplify weed management and make it more efficient, at least at short-term. Overreliance on the same herbicide though leads to the spread of resistant weeds. Here, the objective was to evaluate, with simulations, the impact on the advent of glyphosate resistance in weeds of modifications in agricultural practises resulting from introducing HT maize into cropping systems. First, we included a single-gene herbicide resistance submodel in the existing multispecific FLORSYS model. Then, we (1) simulated current conventional and probable HT cropping systems in two European regions, Aquitaine and Catalonia, (2) compared these systems in terms of glyphosate resistance, (3) identified pertinent cultural practises influencing glyphosate resistance, and (4) investigated correlations between cultural practises and species traits, using RLQ analyses. The simulation study showed that, during the analysed 28 years, (1) glyphosate spraying only results in glyphosate resistance in weeds when combined with other cultural factors favouring weed infestation, particularly no till; (2) pre-sowing glyphosate applications select more for herbicide resistance than post-sowing applications on HT crops; and (3) glyphosate spraying selects more for species traits avoiding exposure to the herbicide (e.g. delayed early growth, small leaf area) or compensating for fitness costs (e.g. high harvest index) than for actual resistance to glyphosate, (4) actual resistance is most frequent in species that do not avoid glyphosate, either via plant size or timing, and/or in less competitive species, (5) in case of efficient weed control measures, actual resistance proliferates best in outcrossing species. An advice table was built, with the quantitative, synthetic ranking of the crop management effects in terms of glyphosate-resistance management, identifying the optimal choices for each management technique.