Metal Ion Content Research Articles

Resistance of mosses Bryum аrgenteum Hedw. and Funaria hygrometrica Hedw. to the effect of heavy metal ions

The tolerance of vegetative and generative clones of mosses of B. argenteum and F. hygrometrica from background and anthropogenically transformed territories to the influence of heavy metal ions was experimentally investigated. It has been established that the increase of the resistance of moss to the influence of heavy metal ions occurs through the activation of growth and physiological-biochemical processes. The level of adaptability of mosses depended on the concentration of toxic ions, the growing environment, and the vital strategy of the moss. It was established that with increasing concentration of lead ions in the environment, the generative propagation of mosses was suppressed, the percentage of germination of spores decreased, the differentiation of protonema and the speed of gametophore development slowed down, the size of cells, number and size of leaves decreased. Obviously, under the influence of elevated lead concentrations, significant changes in metabolic processes occurred in moss cells and showed signs of xeromorphism. The results of the analysis of the rates of gametophyte differentiation and the state of the antioxidant system of mosses B. argenteum and F. hygrometrica, depending on the content of heavy metal ions, show different adaptive capacity. Changes in the rate of gametophyte differentiation and the activity of superoxide dismutase and catalase antioxidant enzymes have been shown to be sensitive biomarkers of the resistance of generative and vegetative moss clones to heavy metal contamination of man-made territories.

Analysis of sorption capacity of natural sorbents in relation to aqueous solutions of heavy metal compounds

The main preconditions emergence of an environmental crisis in the country due to surface water pollution include irrational use of water resources in violation of the environmental requirements, discharge of untreated and insufficiently treated industrial and municipal wastewater into water bodies and inflow of polluting substances from agricultural lands as a result of surface water drainage. The whole set of considered factors leads to depletion and pollution of surface water of Ukraine, reduction of their self-cleaning capacity, degradation, impoverishment and collapse of aquatic ecosystems.
 Excessive content of heavy metal ions in surface water has a negative impact on the environment, causing acute and chronic diseases. Ingress of such pollutants into surface water is almost entirely due to anthropogenic economic activity. Wastewater from chemical, ferrous and nonferrous metallurgy brings a great amount of such pollutants.
 Among various methods used for removing heavy metal ions from aqueous media, sorption methods remain one of the most effective and popular, mainly due to the fact that they ensure a high degree of purification at relatively low costs. Along with the adsorbents traditionally involved in these processes, a number of studies and practical implementations with use of natural dispersed minerals as adsorbents were conducted lately.
 The research aims at studying the sorption capacity and efficiency of natural and modified sorbent such as bentonite clay for purification of aqueous solutions containing heavy metal ions in the form of dissolved compounds and justifying its potential application.
 It studies the efficiency of wastewater treatment aimed at removing heavy metal ions by the natural clay sorbent of bentonite clays of the Cherkaskyi Deposit (Dashukovskyi deposit).
 The paper presents a technique for modification of bentonite clay in order to increase its adsorption capacity for heavy metal ions using the following three methods: physical (thermal), chemical (processing with application of Iron(III) chloride solution) and combined (thermal processing of the original sorbent followed by processing with application of Iron(III) chloride solution).
 It has been experimentally proved that a natural sorbent modified via thermal and chemical processing is characterized by a high absorption capacity to heavy metal ions contained in water solutions, in particular to chromium(VI) ions, copper(II) ions and aluminum(III) ions with the purification degree ranging from 5% to 83%. The highest adsorption rate, 83%, is demonstrated by the combined method of bentonite clay modification, therefore proving the effectiveness of application of environmentally friendly natural sorbents for wastewater treatment processes aimed at removing heavy metal ions. The paper indicates the advantages of wastewater treatment sorption methods allowing removal of pollutants of different origin and any concentration.

ПОРІВНЯЛЬНА ХАРАКТЕРИСТИКА ЕФЕКТИВНОСТІ ЕЛЕКТРОХІМІЧНИХ МЕТОДІВ ДОСЛІДЖЕННЯ ВМІСТУ ВАЖКИХ МЕТАЛІВ У СТІЧНИХ ВОДАХ

Сompare the various modern electrochemical research methods effectiveness used to determine the heavy metals concentration in waste water, based on the literature data. Methodology. Analysis of literature data on the possibilities, advantages and disadvantages of voltammetric, potentiometric, coulometric and conductometric methods for the heavy metals content studying in waste water. Findings. The electrochemical methods are the most common methods for analyzing the composition of waste water. Among their advantages, it should be noted high selectivity, low concentration registration limit (up to 10-10 M for stripping voltammetric methods), simplicity in execution, absence of preliminary long-term samples preparation for analysis, the ability to microvolumes measure without samples destroying and automation of the process for continuous metals concentrations determination in waste water treatment, relatively inexpensive equipment, the ability to determine the concentration of several metal ions in a mixture. Originality. The studies have shown that most often the concentration of heavy metals in waste water determine with the using of the different modifications of voltammetric research methods (polarography and varieties of stripping voltammetry) and potentiometric research methods in particular with highly sensitive and specific ion-selective indicator electrodes. Practical value. The theoretical material on modern electrochemical methods for the heavy metal ions content determining in waste water is generalized.

Transition metal (Nb and W) doped TiO2 nanostructures: The role of metal doping in their photocatalytic activity and ozone gas-sensing performance

Semiconducting metal oxide nanostructures have drawn much attention from the researchers due to several advantages related to their wide-ranging applications, such as photocatalytic activity and gas-sensing performance. In this way, the effect of metal ions on the structural, morphological and electronic properties of the as-prepared samples were investigated by X-ray diffraction (XRD), Raman spectroscopy, UV–visible diffuse reflectance spectra (DRS), X-ray photoelectron spectroscopy (XPS) and electron microscopy techniques. XRD analysis confirmed that all MxTi1−xO2 (M = Nb and W) samples presented only the TiO2 anatase phase despite the different amounts of dopant. Additionally, scanning electron microscopy (SEM) showed that the increased metal ion content leads to a morphological evolution from anisotropic to isotropic nanostructures, which consequently reduces their size. It was observed that the presence of W and Nb as dopants clearly induces a change in the surface characteristics of the nanostructures, favoring the photodegradation of cationic dyes, which does not occur for Rhodamine (RhB) since the photocatalytic mechanism appears strictly related to carrier charges. From the studied samples, W0.29Ti0.71O2 presented interesting ozone (O3) gas-sensing performance, which was evidenced by their working temperature (below 150 °C), sensor response, stability and good range of detection.

A novel durable flame retardant for cotton fabrics based on diethylenetriamine

A novel flame retardant, diethylenetriamine pentamethyl triphosphonate methyl ester ammonium diphosphonate flame retardant (DETA-P), was synthesized and characterized by NMR and FTIR. DETA-P-treated cotton fabrics showed excellent flame retardancy and durability. The limiting oxygen index (LOI) of cotton fabrics treated with 30 wt% DETA-P reached 40.7% and after 50 laundering cycles (LCs), according to the AATCC 61-2013 2A standard, still reached 29.0%. The energy dispersive X-ray (EDX) results of showed that there were P and N elements in CF-3. After 50 LCs, the total metal ion content of DETA-P treated cotton was noticeably lower than that of ammonium salt of diethylene triamine penta methylene phosphonic acid (ADTPMPA)-treated cotton. The scanning electron microscopy (SEM) and EDX results suggested that DETA-P molecules entered the cotton fiber interior. The results of the Fourier transform infrared (FTIR) and durability analyses showed that DETA-P grafted the –OH of cellulose molecules through P–O–C in cotton fibers. Thermogravimetry (TG) results showed that DETA-P changed the thermal decomposition pathway of cotton fibers. The cone calorimetry results indicated that the heat release rate and total heat release of DETA-P-treated cotton were much lower than for untreated cotton. These results showed that the introduction of phosphonate groups and reactive ammonium phosphorus acid groups into a flame retardant molecule was an effective method to improve the flame retardancy and durability of the cotton fibers.

Separation and Recovery Process of Copper (II) and Nickel (II) from Wastewater Using Ion Exchange Fiber

AbstractIn this paper, the parameters affecting the adsorption of CuII and NiII by PAN‐NHx fiber and PAN‐COONa fiber were discussed firstly, such as initial ion concentration, pH, and temperature. Secondly, influence factors toward the separation of CuII and NiII by PAN‐NHx fiber were systematically evaluated by single‐column experiments. The results showed that the PAN‐NHx fiber had good separation of CuII and NiII; NiII accounts for more than 99.00 % of total metal ion content in the initial 1000 mL effluent, while CuII is less than 1 %. With the changed from CCuII: CNiII=90 %:10 % to 95 %:5 %, the ratio of CCuII: CNiII in the treated effluent changed from 6 %: 94 % to 2 %: 98 % (fed flow rate: 0.42 BV min−1). The adsorption capacity of PAN‐NHx adsorption column was well maintained after six cycles. Finally, based on the above laboratory results, a multi‐column process was designed to separate and recover CuII and NiII from wastewater.

Optimization and Field Test of a Chelating Acid System for Scaled Gas Wells in the Hechuan Gas Field

The Hechuan gas field is one of the tight gas reservoirs with the highest formation water salinity in China. The content of metal ions, such as calcium, magnesium, iron, and barium, is as high as 20 g/L. Severe scales in near-wellbore reservoir blocks the gas and liquid flow paths, affecting the normal production of gas wells. The analysis of scale samples shows that the scale compositions in the Hechuan gas field are complex, which are composed of calcium carbonate, calcium sulfate, barium sulfate, iron salt, silicate, and other inorganic scales. To dissolve these scales, 14 kinds of laboratory self-made chelating acids named AST-01 to AST-14, sequentially, were evaluated by the descaling rate, in which the chelating acid AST-01 was selected with a dissolution rate of 77.7%. Meanwhile, the optimal concentration and reaction time of AST-01 were investigated, and the concentrations of the corrosion inhibitor, the iron ion stabilizer, and surfactants were also optimized. Then, a chelating acid descaling formula was obtained, which was 15~20% of AST-01 chelating acid + 1.5~2.0% of corrosion inhibitor + 2.5% of iron ion stabilizer + 0.3% of drainage aid. A pilot field trial of this descaling formula was applied in a Hechuan X1 well. A remarkable result was obtained in that the shut-in tubing pressure recovery rate was increased by 14 times, the gas production was increased by 10 times, and the gas well resumed to produce continuously again.

Nanocomposite of Ceria and Trititanate Nanotubes as an Efficient Defluoridating Material for Real-Time Groundwater: Synthesis, Regeneration, and Leached Metal Risk Assessment.

Ceria-incorporated trititanate nanotube composite (CTNC) was synthesized via a simple two-step wet chemical route for efficient fluoride removal not only from synthetic water but also from groundwater. The synthesized nanomaterial was systematically characterized for its physical and chemical properties. CTNC was shown to be highly porous with a surface area of 267 m2/g. The high surface area exposed majority of its adsorption sites, that is, surface hydroxyl groups, for fluoride removal. The plausible adsorption mechanism deduced based on FTIR and XPS data showed that ion exchange between the surface hydroxyl groups and the fluoride ions in water played a vital role in defluoridation by CTNC. A novel approach was used to quantify the adsorption sites with the use of BET and thermogravimetric analysis. TEM images confirmed the morphology of CTNC to be nanotubes decorated with ceria particles. The analysis of treated water samples for the metal ion content was carried out by an ICP-MS technique. CTNC exhibited characteristics of an ideal adsorbent such as high adsorption capacity, faster kinetics, pH independent adsorption, good regeneration, and negligible leaching of metal ions into the effluent. These attractive characteristics enabled the applicability of CTNC for real-time use.

Bioaccumulation of toxic metals by fungi of the genus Aspergillus isolated from the contaminated area of Ostramo Lagoons

The study compares the ability to bioaccumulate toxic metal ions using microscopic filamentous fungi of the genus Aspergillus isolated from the anthropogenically contaminated site of the Ostramo Lagoons (Ostrava, Czech Republic). The experiment comprised six species of indigenous fungal isolates: A. niger, A. candidus, A. iizukae, A. westerdijkiae, A. ochraceus and A. clavatus. Nutrient liquid media enriched with Cu(II), Zn(II), Ni(II) and Cr(III) were individually inoculated with spores of these fungi. After thirty days of incubation, the content of metal ions in the dried fungal biomass and medium was measured by the AAS. It was found that the average bioaccumulation capacity of selected toxic metal within the tested strains decreases in the following order: A. ochraceus > A. candidus > A. clavatus > A. westerdijkiae > A. iizukae > A. niger. The highest bioaccumulation efficiency was achieved by the A. ochraceus strain which accumulated Cu(II) with an efficiency of 57.42 %, Zn(II) with 56.88 %, Cr(III) with 37.73 %. When comparing the ability of bioaccumulation of the toxic metals, the following was found: Zn(II) > Cu(II) > Cr(III) > Ni(II). Understanding of bioaccumulation processes that take place in fungal cells at the molecular level may lead to better strategies for the application of these interesting microorganisms in bioremediation processes.

Distribution, transfer, ecological and human health risks of antibiotics in bay ecosystems

Antibiotics have been widely detected in bay ecosystems, yet little is known regarding their distribution, composition, sources, ecological and human health risks at the regional scale. We developed a systematic framework to mine data from existing publications and compiled an antibiotic concentration-based dataset containing 439 samples from 30 bays, and compared antibiotics across bays and matrices (water, sediment, and biota). Antibiotic concentrations varied considerably between bays, with hotspots occurring in East Asia. The main categories of antibiotics in waters included sulfonamide and macrolide, while tetracycline, quinolone, and macrolide antibiotics were prevalent in sediments. The main sources of antibiotics in bays included sewage treatment plant effluent, domestic sewage, agriculture runoff, and discharges from mariculture activities. Antibiotics with high ecological risks mainly included sulfamethoxazole, erythromycin, clarithromycin, and oxytetracycline. Erythromycin posed a considerable risk to human health, and the human health risks presented by other antibiotics were negligible. Regional variations of concentrations correspond to the uneven geographic consumption of antibiotics and their removal rate during wastewater treatment. Differences in antibiotics’ composition between matrices are associated mainly with the physicochemical properties of antibiotics (e.g., molecular structure, solubility, and stability) and the content of total organic carbon, metal ions, chlorophyll a, and clay minerals in the sediments. To reduce the ecological and human health implications, priority should be given to the removal of erythromycin, sulfamethoxazole, oxytetracycline, and clarithromycin, with a special focus on their treatment in the Asian bay areas.

Effects of alkali oxides and ion-exchange on the structure of zinc-alumino-silicate glasses and glass-ceramics

Types and contents of alkali metal ions play important role on crystallization and ion-exchange properties in glasses. In this work, effects of Na2O/K2O ratio on crystallization and ion-exchange properties of zinc-alumino-silicate glasses were investigated. The crystalline phases precipitated in glasses changes from ZnO to β-Zn2SiO4 with the progressive replacement of K2O by Na2O in parent glasses. Ion-exchange depth of layer (DOL) decreases gradually with the increase in Na2O content in parent glasses. Precipitation of ZnO and β-Zn2SiO4 nanocrystals facilitated the ion-exchange and enlarged the DOL. Na+ and K+ ions were doped into ZnO and β-Zn2SiO4 nanocrystals during heat-treatment, and the extent of doping was facilitated by ion-exchange. Vickers hardness were improved significantly with the crystallization and ion-exchange. Results reported here are valuable for the controlled preparation and chemical strengthening of ZnO and β-Zn2SiO4 glass-ceramics.

Metal ions immobilized on polymer ionic liquid as novel efficient and facile recycled catalyst for glycolysis of PET

Environmental pollution aroused by accumulation of waste PET has attracted worldwide attention. Metal chloride as Lewis acid catalyst has excellent catalytic performance in enormous organic reaction. However, the high solubility of the metal chloride in ethylene glycol and the residue of metal ions in the product will have an adverse impact on the subsequent process. In this work, polymer ionic liquid containing [NTf2]− which is insoluble in ethylene glycol at room temperature was synthesized and used to immobilize metal ions to catalyze glycolysis of PET. After reaction, the polymer ionic liquid-metal ion catalyst could be recovered at room temperature by simple filtration. PET conversion reached 95.4% and BHET yield reached 77.8% using PIL-Zn2+ as catalyst at 195 °C for 120 min. Ionic liquid was characterized by FT-IR, NMR and ESI-MS. Interaction between ionic liquid and metal ions was characterized by FT-IR. The interaction energy of polymer ionic liquid-metal ion complex is higher than that of ethylene glycol-metal ion complex by DFT calculation (Density functional calculation). The both content of metal ion in polymer ionic liquid-metal ion complex and catalytic performance of as-synthesized catalysts did not obviously decrease after the catalyst was reused for five times. This work mainly provided a way of recovering catalyst and promote development of glycolysis of PET.

Impacts of Adjunct Incorporation on Flavor Stability Metrics at Early Stages of Beer Production

The fresh flavor of a beer brand is one of its most important quality parameters and should be retained as long as possible through shelf-life. Early stages of beer production can have significant impacts on beer flavor stability. The use of cereal adjuncts – either malted or unmalted – is now widespread practice in brewing. This laboratory mashing study investigated the impacts of incorporating common solid adjuncts (corn and rice) at increasing grist percentages (0-50%) on flavor stability indicators measured in wort. Sweet worts were analysed for metal ion levels (ICP-MS), thiol content (RP-HPLC), oxidative stability (EPR spectroscopy), staling aldehydes (HS-SPME-GC-MS), trihydroxy fatty acids (GC-FID), t-2-nonenal potential (GC-MS), color and thiobarbituric acid (TBI). Mashing conditions for each formulation were adjusted in order to achieve target FAN values. Unmalted rice or corn adjuncts significantly reduced the total metal ion content, color, TBI and staling aldehydes in sweet worts at 50% adjunct incorporation (p < 0.05), relative in each case to the respective all-malt control mash. Our findings showed that unmalted rice or corn adjunct incorporation generally improved flavor stability metrics in sweet worts when similar mashing conditions were applied, whilst increasing the length of the ‘protein stand’ in mashing to reach target FAN in general had a negative impact on flavor stability indicators – e.g., wort T150 values significantly decreased in each recipe at 25% and 35% adjunct relative to the 12.5% adjunct brew but increased again at 50% adjunct, presumably due to the prolonged proteolytic stand employed to achieve target FAN content.

Comprehensive understanding the transition behaviors and mechanisms of chlorine and metal ions in municipal solid waste incineration fly ash during thermal treatment

Municipal solid waste incineration fly ash is classified as the hazardous waste because of its high levels of heavy metals alkali chlorides, and polychlorinated dibenzo-p-dioxins. Thermal treatment is widely used for fly ash treatment because of its advantages of reduction and harmless. The transformation behaviors of chlorine and metal ions during the thermal treatment of fly ash has a significant impact on the harmless and resource of fly ash. At present, the migration behaviors of chlorine and metal ions during thermal treatment of fly ash is not clearly demonstrated. In this manuscript, the phase compositions, transformation behaviors, the variation of mass and content of chlorine and various metal ions were analyzed through diverse characterization methods under different sintering temperatures to understand the migration behaviors of chlorine and metal ions during thermal treatment. Roasting experiments showed that the migration behaviors of heavy metals and chlorides were consistent. The chlorine, sodium, potassium and heavy metal ions can be removed sharply while the calcium, aluminum, magnesium and iron were decreased slightly when the roasting temperature was above 750 °C. The findings also suggested that removed chlorides were soluble chlorides and unstable crystals in municipal solid waste incineration fly ash were inclined to formed steady structure under high temperature. The structure of roasted fly ash became denser and generated ceramic-like particle due to thermal agglomeration and chemical reactions.

MICROBIOLOGICAL AND SANITARY - CHEMICAL CHARACTERISTICS OF WASTEWATER FROM PHARMACEUTICAL COMPANY

Aim. Оssessment of wastewater from a pharmaceutical company according to sanitary-microbiological and chemical indicators to determine the method of treatment and remediation of them from pollutants and pathogens. Methods. In sanitary and bacteriological studies, classical microbiological methods were used to determine the total microbial number of pathogenic bacteria. Determination of the concentration of ammonium, nitrite and nitrate in wastewater samples from a pharmaceutical company was carried out spectrophotometrically using the chemical reaction of ions to Nessler's reagent, Griss reagent, and phenol sulfide acid. The content of heavy metal ions was determined by the method of electrothermal AAS using the device "Saturn-2", by the photometric method using 4-aminoantipyrine – phenol, by the extraction-photometric method – by surfactants, by the method of infrared spectrometry – by petroleum hydrocarbons. Results. It was experimentally confirmed that the total microbial count in wastewater samples from a pharmaceutical company slightly exceeded the standard value. The BGKP index and the E. coli index were within the normal range. The pathogenic bacteria Salmonella moscow and Klebsiella pneumoniae were found in the wastewater of pharmaceutical company. The contamination of pharmaceutical stock can be judged by the 8.5 times excess of the concentration of ammonium ions in them compared to the MPC. The results of chemical analysis of wastewater samples from a pharmaceutical company indicate their multicomponent composition.Of the heavy metal ions, ions of zinc, copper, lead, hexavalent chromium and cadmium were mainly detected. With the exception of cadmium ions, the concentration of heavy metal ions was 1.4–7.2 times higher than the MPC norm. Anionic surfactants predominated in pharmaceutical stocks – their concentration was 8.2 ± 0.7 mg/dm3. The level of phenolic and oil pollution of wastewater was minimal in comparison with the content of anionic surfactants, which could be caused by the activity of aboriginal strains of bacteria-destructors with a high phenolic capacity. Conclusion. The results of sanitary-microbiological and chemical analysis of wastewaters of a pharmaceutical company indicate their multicomponent nature and environmental hazard – they contain pathogenic bacteria Salmonella moscow and Klebsiella pneumoniae and pollutants of various nature: heavy metal ions Cu (II), Cr (VI) and Pb (II) at a concentration of 36.0 ± 14 μg/dm3, 3.0 ± 0.4 μg/dm3 and 14.0 ± 0.7 μg/dm3, respectively, and organic pollutants – phenol, oil products and anionic surfactants at a concentration of 0.003 ± 0.0006 mg/dm3, 0.81 ± 0.05 mg/dm3 and 8.2 ± 0.7 mg/dm3, respectively. Werecommend to carry out a comprehensive purification of wastewater from a pharmaceutical company from phenol, heavy metal ions [Cu (II), Cr (VI), Zn (II)], oil products, anionic surfactants and pathogens.

The effect of carbonization temperature on the capacity and mechanisms of Pb(II) adsorption by microalgae residue-derived biochar

This study investigated the adsorption characterizations and mechanisms of lead (Pb) on biochar-derived microalgae residue (MB) produced at different pyrolytic temperatures. Six different MB samples were prepared from Chlorella sp. (CB) and Spirulina sp. (SB) in the temperature range of 200–600 ℃, and microalgae residue power (MP) was used as a control. The effect of pH, adsorption kinetics and isotherms were studied for the different MBs, and a chemical analysis of Pb2+-loaded MP and MB was performed by SEM-EDS, XRD, XPS, FTIR, and Boehm titration. The results showed that Pb2+ adsorption on MP and MB was a monolayer chemical adsorption process. Precipitation with minerals, metal ion exchange, oxygen/nitrogen-containing functional groups (OFGs/NFGs), and coordination of Pb2+ with π electrons jointly contributed to Pb2+ adsorption on MP and MB. More specifically, the contribution of each mechanism depended on the pyrolytic temperature. The contribution of surface complexation and ion exchange decreased with increasing pyrolytic temperature due to the loss of OFGs/NFGs and decreasing metal ion content, while the contribution of precipitation and Pb2+-π interaction significantly increased. Overall, precipitation with minerals and ion exchange dominated Pb2+ adsorption on MP and MB, which accounted for 65.20–74.40% of the total adsorption capacity. Surface precipitation contributed to a maximum adsorption capacity for high-temperature CB and SB (600 ℃) of up to 131.41 mg/g and 154.56 mg/g, respectively. In conclusion, MB adsorbents are a promising material for the remediation of heavy metal-bearing aquatic environments.

Isolation, Characterization and Identification of a New Lysinibacillus fusiformis Strain ZC from Metlaoui Phosphate Laundries Wastewater: Bio-Treatment Assays

The aim of the present study is to isolate, characterize and identify a novel strain ZC from the Metlaoui phosphate laundries wastewater (MPLW). The chemical characterization of this phosphate rich effluent showed an alkaline pH and is saline, highly turbid and rich in suspended matter and total solids. The MPLW samples were loaded with potentially toxic metals, presented in decreasing order as follows: magnesium (5655 mg L−1), potassium (45 mg L−1), lead (1 mg L−1), iron (0.7 mg L−1), cadmium (0.5 mg L−1), copper (0.3 mg L−1) and zinc (0.1 mg L−1). Due to the high COD/BOD5 ratio, a poorly biodegradable organic load is underlining. The newly isolated strain was identified as Lysinibacillus fusiformis using 16S rDNA sequencing analysis. The viability of this new strain was tested in presence of the zinc, lead, cadmium, manganese and copper at 1, 10 and 100 mM. The L. fusiformis survival, under metallic stress, was inversely proportional to metal ion concentrations, while lead and zinc were the most toxic ones using MTT assay. Then, the newly isolated strain was characterized in terms of enzyme production, proteomic alteration and antibiotic resistance. The strain ZC revealed some modifications in the biochemical and enzymatic profiles by either the appearance or/and the disappearance of some activities. In addition, the increase in metal ions stress and concentrations was proportional to the adherence and to the hydrophobicity. The presence of the metal ions suggested the change of sensitivity to the resistance of this strain towards tobramycin, kanamycin, neomycin, netilmicin and cefoxitin, showing an increase in the MARindex. The strain ZC, used as a biological tool for MPLW treatment, showed a reduction in the metal ion contents. This reduction was due to accumulation and/or adsorption, showing a bioprocessing performance of the newly isolated L. fusiformis.

Effect of Phytoremediated Port Sediment as an Agricultural Medium for Pomegranate Cultivation: Mobility of Contaminants in the Plant

Although the dredging of ports is a necessary management activity, it generates immense quantities of sediments, that are defined by the European Union as residues. On the other hand, the relevant peat demand for plant cultivation compromises its availability worldwide. In this context, the present work wanted to find an alternative substrate in order to replace and/or reduce the use of peat in agriculture, through the study of the suitability, concerning the exchange of substrate–plant–water pollutants, of the dredged remediated sediments as a fruit-growing media. Forty-five pomegranate trees (Punica granatum L. cv “Purple Queen”) were cultivated in three types of substrates (100% peat as a control, 100% dredged remediated sediments and 50% both mixed). The metal ion content and pesticide residues were analysed in the different plant parts (root, stem, leaves and fruits) and in drainage water. The results showed a limited transfer of pollutants. All the pollutants were below the legal limits, confirming that the dredged sediments could be used as a growing media, alone or mixed with other substrates. Thus, the results point out the need to open a European debate on the reuse and reconsideration of this residue from a circular economy point of view.

Determination of influence of pH on reaction mixture of ferritation process with electromagnetic pulse activation on the processing of galvanic sludge

This paper considers prospects for increasing the level of environmental safety of industrial enterprises as a result of the implementation of resource-saving technology of processing galvanic sludge using the ferritization method. The effectiveness of the use of electromagnetic pulse discharges for resource-saving activation of the ferritization process with the extraction of heavy metal ions from sludge (Fe, Ni, Cu, Zn) has been confirmed. The influence of key parameters of the process such as the pH value of the reaction mixture and the initial concentrations of metals in the solution on the quality of processing galvanic sludge by ferritization has been experimentally investigated. It was determined that with an increase in the pH value from 8.5 to 10.5 the residual concentrations of metal ions decrease to the values of 0.1÷0.25 mg/dm3 regardless of the total initial concentrations. It has been established that the technique of electromagnetic pulse activation ensures an adequate degree of extraction of metal ions of 99.9 %; it also has indisputable energy advantages compared to the thermal method: energy costs are reduced by more than 60 %. That indicates the suitability of purified water for reuse in galvanic production in terms of the requirements for the content of heavy metal ions in it. In addition, the structural studies of ferritization sediment samples have been carried out. The sediment is characterized by the maximum content of crystalline ferromagnetic phases of ferrite. It was established that an increase in the pH of the initial reaction mixture leads to an increase in the ferrite phase in sedimentation: at pH=10.5, phases were detected, which are characterized by a maximum ferrite content (exceeding 76 %). The proposed resource-saving ferritization process prevents environmental pollution, ensures efficient and rational utilization of raw materials and energy in the industry; it also makes it possible to obtain commodity products from industrial waste.

Composite Carbon Foams as an Alternative to the Conventional Biomass-Derived Activated Carbon in Catalytic Application.

The suitability of a new type of polyurethane-based composite carbon foam for several possible usages is evaluated and reported. A comparison of the properties of the as-prepared carbon foams was performed with widely available commercial biomass-derived activated carbon. Carbon foams were synthesized from polyurethane foams with different graphite contents through one-step activation using CO2. In this work, a carbon catalyst was synthesized with a moderately active surface (SBET = 554 m2/g), a thermal conductivity of 0.09 W/mK, and a minimum metal ion content of 0.2 wt%, which can be recommended for phosgene production. The composite carbon foams exhibited better thermal stability, as there is a very little weight loss at temperatures below 500 °C, and weight loss is slower at temperatures above 500 °C (phosgene synthesis: 550–700 °C). Owing to the good surface and thermal properties and the negligible metallic impurities, composite carbon foam produced from polyurethane foams are the best alternative to the conventional coconut-based activated carbon catalyst used in phosgene gas production.