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Lithium mining driven by the growing demand for lithium-ion batteries, has environmental consequences linked to soil and water pollution. Nevertheless, research on the environmental impacts of lithium extraction still needs to be improved, highlighting the imperative for additional research. The article addresses the potential impact of the C57 lithiniferous feldspar mine on water quality, specifically focusing on surface, groundwater and spring water samples collected at the mining site and surrounding area in Gonçalo (Guarda, Portugal). The objective is to evaluate the environmental consequences of mining activities, with particular emphasis on mineral leaching. This study aims to evaluate the water quality around the C57 mine and the potential environmental impacts of mining operations. Water samples were collected from different sources, such as surface, underground, and spring waters, and chemical analyses were carried out to determine concentrations of different parameters, which were later compared with national and international reference guidelines. In addition to analysing the water samples, weathering tests were carried out using the Soxhlet extractor method to simulate the leaching of minerals over a shorter period (about 125 days). The concentrations of the analysed elements by atomic absorption spectroscopy (Al, Ca, Cd, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb and Zn) in the weathering solutions were generally low and decreased throughout the testing period, with significant concentrations of aluminium and chromium exceed Canadian environmental quality guidelines for surface waters. The detected lithium concentrations are quite different, ranging from 8.7 to 19.8 μg/L in surface waters, from 6.9 to 74.1 μg/L in groundwater, and from 25.6 to 35.4 μg/L in spring waters, but are all below the US EPA (2021) recommendations threshold of 0.7 mg/L. Based on the findings, the article concludes that there is currently no clear evidence to indicate the environmental impact of mining activities on water quality in the analysed samples. However, weathering tests suggest potential long-term implications regarding the leaching of specific chemical elements, particularly aluminium and chromium. [ABSTRACT FROM AUTHOR]

SrO has attracted attention for its use as a heterogeneous catalyst in producing biodiesel from transesterification owing to its high alkaline character and low solubility in methanol. In studies conducted in this decade, reaction conditions such as the methanol–oil molar ratio, reaction time, catalyst loading and temperature have been optimized in these systems. Furthermore, several works have been carried out to improve the physicochemical properties and increase the leaching resistance of this material. Thus, the new trends in using SrO in transesterification reactions are that this oxide should be supported or combined with Al2O3, TiO2, ZrO2, or Fe2O3, CaO, metal–organic frameworks, zeolites or La2O3. It has been observed that strontium can form mixed crystalline phases with these oxides by increasing the (M2+O2−) pairs and Lewis basicity of the oxygens, resulting in increased basicity and catalytic activity. Moreover, the transition metal oxides may provide Lewis acidity. Hence, these strontium‐containing catalytic systems have demonstrated a bifunctionality that can perform esterification and transesterification reactions at the same time. In addition, the combination of these oxides decreases the leaching of the catalyst. Other materials such as metal–organic frameworks, zeolites, and La2O3 have been studied as SrO supports, showing that they can be used in oil transesterification reactions. [ABSTRACT FROM AUTHOR]

We report the elaboration of translucent ZnGa 2 O 4 ceramics by an innovative process, the sintering by Spark Plasma Sintering (SPS) of spinel ceramic powder obtained by the lixiviation of glass-ceramics. Indeed, a selective dissolution of the silica-rich glass matrix allows isolating ZnGa 2 O 4 nanocrystals embedded in the silicate glass-ceramic. This glass-ceramic is elaborated from the parent glass of composition 55 SiO 2 - 5 Na 2 O - 17 ZnO - 23 Ga 2 O 3 (% mol) that undergoes a subsequent heat-treatment at 1100 °C under air leading to the crystallization of zinc gallate spinel nanocrystals with size in the 20–60 nm range. Lixiviated nanocrystals are collected and sintered by SPS to get a bulk ceramic. While the transmittance of this ceramic is only 60% at 4.5 µm, which is lower than the theoretical transmittance (82.5%), these first results are still promising and pave the way to new transparent ceramic processing route. Indeed, glass crystallization combined with selective lixiviation process is a powerful, non-conventional elaboration process that can further allow the stabilization and isolation of metastable crystalline phases with interesting functional properties. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An advertent meltdown of radioactive source during steel smelting generates electric arc furnace dust (EAFD) polluted with 137Cs. The removal efficiency of 137Cs from EAFD was assessed by the lixiviation method using different solvents and at various radioactivity levels. More than 90% of 137Cs was removed from EAFD by rinsing with 0.5 M HNO3 and H2SO4, while removal efficiencies of deionized water, tap water, CsCl and Ca(OH)2 ranged from 84 to 89%. Mass loss and composition of the EAFD samples were investigated and compared. Results can assist in the decision-making of different solvents for large-scale removal of 137Cs from EAFD.

Abstract Boulders are an important material in debris flow and their source is coupled with spheroidal weathering profiles that produce corestones. The goal of this work was to establish the geochemical transformations that produced corestones and distinguished them from the surrounding grus in two tropical granite weathering profiles (P1 and P2). Sampling was not performed in a vertical profile; instead, we gathered 13 (P1) to 16 (P2) samples displaying different weathering degrees (corestone and saprolite) and spatial positions in the profiles. We conducted the geochemistry (EDXRF/EDX and INAA) and mineralogy (petrography and XRD) of the samples. The CIA values ranged from 46 (corestones) to 93 (saprolite). Granite spheroidal weathering under a tropical mountainous slope develops mostly due to feldspar weathering (foremost plagioclase) in the following sequence: porosity growth, kaolinite, and gibbsite crystallization. Zircon weathering stability and its probable mobility as grain along the weathering profile play an important role in REE concentration. Spheroidal weathering is mainly a lixiviation process, yet specific locations (below the individualized corestones) presented REE enrichment due to translocation. They are hosted mainly by clay minerals and, to some extent, by amorphous Fe oxyhydroxide. The evolution of spheroidal weathering results in a vertical patchy weathering profile.

Green roofs are very popular and their individual surface area is constantly growing. Considering that the organo-mineral materials used in planting growing media (GM) are often non-renewable resources, the search for alternative materials from waste recycling is a challenge. Among these, recycled polyurethane (PU) foams are light and porous. The objective of this study was to evaluate the potential agronomic valorisation of PU foams for extensive green roofs. Three GM based on compost, PU foam and topsoil were developed and tested in situ for 18 months along with four plant species in containers containing 15 cm of GM. The agronomic properties of the GM and their contaminant contents were evaluated, as well as the plant aerial and root biomasses and trace element levels. The main results of this work are that GM are suitable for plant growth. Compost ratio effect resulted in a lower pH and higher exchangeable cations in GM1, whereas topsoil proportion effect mainly decreased macroporosity and increased nutrient contents. Furthermore, due to the high trace element load in the compost, hyperaccumulator plants such as Hypericum calycinum and Stipa tenuissima should be preferred. Ecotoxicological analyses will be carried out to validate the absence of risk of PU foam contaminants being released in the environment before proposing these types of GM to green roof developers. [ABSTRACT FROM AUTHOR]

CaO-supported Li and K catalysts were studied for transesterification reactions. The CaO was obtained from calcined commercial limestone. The catalysts were impregnated with LiNO3 and KNO3, reaching a loading of 3 wt.% of alkali metal. The synthesized catalysts were characterized by thermogravimetric analysis, X-ray diffraction, and Hammett indicators. The catalytic transesterification evaluations of tributyrin, triestearin, and triolein with methanol were carried out with methanol/triglyceride molar ratio of 20:1 and 3 wt.% of catalyst at 60 °C for one hour. It was found that the strength of the alkaline sites increased when alkali metal was added to the support since these metals prevented the formation of Ca(OH)2. The Li/CaO catalyst presented higher basic strength and higher catalytic activity. It was observed that short-chain triglycerides were found to be more reactive than long-chain and unsaturated ones; likewise, saturated chain triglycerides are more reactive than unsaturated ones due to fewer interactions with the active sites. Finally, potassium avoided the lixiviation of the catalysts to the liquid phase. [ABSTRACT FROM AUTHOR]

An experiment was carried out during four harvests (two in the cold season and two in spring) with the objective ofdetermining the N losses by leaching and volatilization as well as their dynamics in a Brown Grayish soil in the Central Cuban region at the Experimental Station of Soil “Escambray” in corn crop. Six N levels were applied (0, 60, 120, 180, 240 y 300 kg ha-1 of N) a third of which with ammonium sulfate when planting and the remaining 35 days with urea. Volatilization of ammonium in form of ammonia was determined using Nömmik’s method in levels 0, 120 and 240 kg ha-1 to 3, 7, 14, 21, 28 and 35 days after fertilization. The washing of NO3- and NH4+ was quantified using a lysimeter type Ebermeyer. Ammonia losses due to volatilization increased along with N doses in the two seasons, reaching its maximum level between the 3rd and 7th days after the second urea fertilization with values of 25 kg ha-1. NH4+ leaching was insignificant. while NO3- losses increased along with the doses and were approximately 13 % of the applied N reaching values of 47 kg ha-1 in the dose of 300 kg ha-1. It is concluded that in Brown Grayish soil the greatest losses due to ammonium volatilization occur with urea and the greatest leaching occurs in NO3-

The extraction of compounds present in Cannabis sativa biomass from Colombian crops was studied using a semi-continuous lixiviation process. To this effect, three extraction stages were implemented, in which successive transfers were carried out at fixed times, seeking to emulate a continuous countercurrent process. In this way, the intention is to provide the Colombian agroindustry with an extraction method that is efficient and requires a lower initial investment than other techniques such as supercritical fluid extraction. Absolute ethanol was used as solvent, and constant temperature and stirring speed were applied. The obtained results indicate that, once the process is stabilized, extracted mass percentages (with respect to the total mass on a dry basis) of 10,5% at 40 °C and 9,5% at 19 °C are achieved, which are competitive compared to the 11,07% achieved through Soxhlet extraction. Besides, the proposed process is clearly a better alternative than a single-stage extraction method, through which it was possible to extract 5% of the mass. Five cannabinoids were identified in the obtained extract, and, with the proposed process, it was possible to extract 66% of cannabidiol present in the original biomass.

An experiment was carried out during four harvests (two in the cold season and two in spring) with the objective of determining the N losses by leaching and volatilization as well as their dynamics in a Brown Grayish soil in the Central Cuban region at the Experimental Station of Soil "Escambray" in corn crop. Six N levels were applied (0, 60, 120, 180, 240 y 300 kg ha-1 of N) a third of which with ammonium sulfate when planting and the remaining 35 days with urea. Volatilization of ammonium in form of ammonia was determined using Nömmik's method in levels 0, 120 and 240 kg ha-1 to 3, 7, 14, 21, 28 and 35 days after fertilization. The washing of NO3- and NH4+ was quantified using a lysimeter type Ebermeyer. Ammonia losses due to volatilization increased along with N doses in the two seasons, reaching its maximum level between the 3rd and 7th days after the second urea fertilization with values of 25 kg ha-1. NH4+ leaching was insignificant. while NO3- losses increased along with the doses and were approximately 13 % of the applied N reaching values of 47 kg ha-1 in the dose of 300 kg ha-1. It is concluded that in Brown Grayish soil the greatest losses due to ammonium volatilization occur with urea and the greatest leaching occurs in NO3-. [ABSTRACT FROM AUTHOR]

Copyright of Phytothérapie is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract A commercial equilibrium FCC catalyst of the octane-barrel type was subjected to lixiviation treatments with both acidic (HNO 3) and basic (NaOH) solutions in order to modify its textural and acidic properties. The alkaline lixiviation doubled the mesopore volume in the commercial catalyst, while the acidic treatment increased the concentration of crystalline component in the catalyst. The catalytic performances of the parent and modified catalysts in the immediate conversion of vapors from pine sawdust fast pyrolysis were evaluated in a fixed bed reactor at 550 °C using mass catalyst to bio-oil and tar ratios from 3 to 8. The modified catalysts both produced more hydrocarbons and less coke than the parent commercial catalyst. In turn, comparing the modified samples, the one subjected to alkali treatment was more effective in deoxygenating the pyrolysis vapors, resulting in higher hydrocarbon yields (up to 13.2%) and lower coke yields than the acid modified catalyst, a fact assigned to the higher mesoporosity which improves the diffusion transport of bulky coke precursor molecules. The acid modified catalyst allowed a higher extension of the reaction pathway, the selectivity to aromatic hydrocarbon products being much higher (up to 95.5% of hydrocarbons in the gasoline boiling range). Highlights • Acid and basic lixiviation of equilibrium FCC catalysts improved properties to upgrade bio-oils. • Alkaline treatment improved mesoporosity, the acid treatment increased proportion of zeolite. • Pine sawdust bio-oil was upgraded over modified catalysts in a pyrolysis-conversion reactor. • The desilicated catalyst was more effective in deoxygenating bio-oil, yielding less coke. [ABSTRACT FROM AUTHOR]

Average annual precipitation (AAP) is one of the principal environmental factors that regulates processes in terrestrial ecosystems. The effect of AAP on the availability of edaphic nutrients is poorly understood, especially in tropical zones with high rainfall. In order to evaluate the effects of high AAP on the availability of soil N, P, and K, physicochemical parameters were measured in soils of three tropical rainforests in the Chocó biogeographical region with different AAPs (7,500, 8,000, and 10,000 mm yr-1). Furthermore, a bibliographical review was carried out that including studies for distinct tropical Ultisols and AAP ranging from 1,800 to 10,000 mm yr-1. The evaluated soils presented extreme acidity with high contents of Al, organic matter (OM) and total N, and low quantities of P, Mg, and Ca. The K concentrations were intermediate and the effective cation exchange capacity (ECEC) was low. On the other hand, in the evaluation of the influence of the AAP on the availability of N, P, and K in the soil, contrasting tendencies were observed. On one side, a positive curvilinear relationship was found between the availability of N and the increase in the AAP. On the other side, the available P content significantly decreased with increasing AAP. In conclusion, the excessive AAP resulted in increases in total N and low availability of P, thereby altering the dynamics of the nutrients and the carbon balance of the tropical forest

Innovative composites based on an amorphous-carbon matrix containing a second phase ZnO oxide and/or highly dispersed Zn metallic were synthesized via a modified Pechini route, in which a partial pyrolysis method was reached. Studies of adsorption in the dark and the photocatalytic activity for the cationic azo-dye, basic blue 41, and degradation were carried out. X-ray diffraction patterns for the carbon matrix and its composite with Zn show characteristics of the amorphous carbon. The infrared in the mid region of the composite prepared with ZnO and Zn exhibit vibrational bands related to bonds zinc oxide. The surface pH of the material is the main factor responsible for the adsorption of the azo-dye, but the contribution of mesopores favored the diffusion of molecules from the bulk of solution to the pore framework. Esters-like functional groups on the surface of carbons hinder the adsorption of the azo-dye. When Zn is embedded within amorphous carbon the photocatalytic activity of the composites showed up to 2.4 higher than neat ZnO. The enhancement in the photocatalytic activity and stability of C/ZnO/Zn and C/Zn composites is discussed in terms of a protector effect by the carbon layers inserted in composites. Carbon layers are responsible to inhibit the lixiviation of ZnO particles along irradiation.

Extraction of seed oil initially consisted in physicochemical study of the seed, in order to meet their nutritional content by performing various analyzes as moisture, ash, fat, phosphorus, proteins and carbohydrates. Then we proceeded with oil extraction equipment using solid-liquid extraction, Soxhlet using hexane as a solvent using the factorial design of the type 23. After, the crude oil was characterized and refined by the methodology of COVENIN norms, where the oil presented potential properties to elaborate soap in the cosmetic industry. Finally, a lipid profile was obtained by a gas chromatographic, the results showed highly unsaturated fatty acid contents (linoleic and oleic) that gives it the potential to be applied as a capable oil with excellent properties and quality to human consume.

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The capacity of different soils to capture silver nanoparticles (AgNPs) by measuring changes of an AgNP intrinsic property such as the plasmon for the first time, was studied. In-tube solid-phase microextraction (IT-SPME) coupled on-line to capillary liquid chromatography (CapLC) with diode array detection (DAD) was employed for measuring the interactions between soil and in-contact AgNP dispersions. Its achieved LOD 9 pM assures quantitative retention measurements and selectivity for soil lixiviation was suitable. Electronic microscopy was employed for corroborating the entrapped Ag into the soils. Capture % of AgNPs was calculated in compost (>99%), mountain (>99%), orchard (15 ± 1%) and urban (48 ± 1%) soils. Also, the relation between some soil characteristics: solid organic matter (SOM), composition, pH, redox potential (Eh), electrical conductivity (EC) and size, and the retention of these metallic nanoparticles was studied. The results have also been estimated after sieving and the capture % of AgNPs was similar in the resulting fractions. AgNP adsorption on a given soil is mainly affected by its organic matter content for studied soils with higher SOM amounts (23–62%). However, for the soils with lower SOM amounts (4.6–8.3%) the role of HAs could prevent AgNP deposition onto soils. The proposed methodology can be utilized for quickly assessing the potential of a given soil considering its properties for capturing these nanoparticles, which can come at handy for their administration, characterization or remediation. [ABSTRACT FROM AUTHOR]

The objective of the present work was to determine the mobility of flumioxazin in Argisol, as a function of two pluviometric indices, as well as possible influences of the chemical and physical properties, on the action of the herbicide. 32 PVC tubes were used (10 cm in diameter by 50 cm in height). These containers were completely filled with the Argisol collected in the arable layer of an area where there was no herbicide application. Once the flumioxazin (50 g i.a. in 200 L/ha) was applied, the treatments were applied. Then, rainfall of 10 mm per day was simulated to reach the desired levels of rainfall (40 and 80 mm), so that the tubes were dismantled and 5 sorghum seeds (Sorghum bicolor) were seeded each depth (2.5; 5; 10; 15 and 30 cm) in the profile of the tubes. These were maintained for 15 days under field conditions to carry out the initial evaluation. Height, dry matter, and phytointoxication were evaluated to analyze possible changes that could be characterized as herbicide effects. Under experimental conditions, flumioxazin was sparingly mobile, remaining in the superficial layer (2.5 cm). [ABSTRACT FROM AUTHOR]

Organochlorine pesticides present in sewage sludge can contaminate soil and water when they are used as either fertilizer or agricultural soil conditioner. In this study, the technique solid-liquid extraction with low temperature purification was optimized and validated for determination of ten organochlorine pesticides in sewage sludge and soil samples. Liquid-liquid extraction with low temperature purification was also validated for the same compounds in water. Analyses were performed by gas chromatography-mass spectrometry operating in the selective ion monitoring mode. After optimization, the methods showed recoveries between 70% and 115% with relative standard deviation lower than 13% for all target analytes in the three matrices. The linearity was demonstrated in the range of 20 to 70 µg L-1, 0.5 to 60 µg L-1, and 3 to 13 µg L-1, for sludge, soil, and acetonitrile, respectively. The limit of quantification ranged between 2 and 40 µg kg-1, 1 and 6 µg kg-1, and 0.5 µg L-1 for sludge, soil, and water, respectively. The methods were used in the study of pesticide lixiviation carried out in a poly vinyl chlorine column filled with soil, which had its surface layer mixed with sludge. The results showed that pesticides are not leached into soil, part of them is adsorbed by the sewage sludge (4-40%), and most pesticides are lost by volatilization. [ABSTRACT FROM AUTHOR]

This report aims to disclose interactions between semi-direct recycling concepts, corrosion analysis of hard metals and possible leaching mechanisms. Accordingly, an examination reveals chemical kinetic dependencies via leaching a cutting insert in formic acid inclusive an oxidant. Currently, contradictions and issues in literature slow down the progress of semi-direct technologies in comparison to direct and indirect recycling concepts. Additionally, corrosion investigations show helpful explanations for leaching mechanisms of cobalt from cemented carbides, which so far are not connected to reclamation reviews. In order to obtain reliable data from experiments, the statistical software Modde 11 assists to apply a design of experiments and to perform a multiple regression analysis. Nevertheless, the experimental setup decides the result of the rate law investigation. The sample geometry and leaching conditions in the reactor affect the outcome in the form of a kinetic model equation. Finally, an empirical kinetic law with its dependencies inside the experimental boundaries presents potential ways to favorably influence cobalt leaching out of cemented carbides. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Corn (Zea mays L.) is the second most cultivated cereal in the world and is used as raw material for different kind of industries. To date no reports about obtaining giberellic acid (GA3 ) from corn have been found. In the present study two methods for extracting solid samples were evaluated: lixiviation and dynamic sonication-assisted solvent extraction (DSASE), for obtaining giberellic acid from corn germinated seeds. In lixiviation, the physical method (agitation and sonication), solvent, and time were the parameters analyzed; while in DSASE the variables were: solvent, flow, and time. The most efficient technique was DSASE employing acetonitrile-formic acid 5% (80:20, v:v) as solvent at a flow o f 0,4 mL/ min for 25,0 min, obtaining a concentration o f 30,012 mg/kg giberellic acid. Identification and quantification were performed by high performance liquid chromatography (HPLC) with diode array detector (DAD). These results showed that dynamic sonication-assisted solvent extraction (DSASE) is a novel and powerful alternative technique for obtaining giberellic acid, because o f its high efficiency; low solvent consumption and simplicity in obtaining the extract. [ABSTRACT FROM AUTHOR]

Two different precursors of zinc oxide were prepared via the ammoniacal ammonium carbonate leaching of the black mass obtained during the recycling of alkaline batteries. For a concentration of 0.1 mol/L of ammonium in the leaching solution, zinc basic carbonate, was obtained, while for higher ammonium concentrations (0.5 and 1 mol/L), zinc ammonium carbonate was the final product. These precursors were characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA/DTG) and Scanning electron microscopy (SEM), and calcined to obtain ZnO. Raman spectroscopy, X-ray diffraction and Transmission electron microscopy (TEM) analysis of the resulting zinc oxide samples indicated a wurtzite hexagonal lattice with a parameter values ranging from 3.23 Å to 3.30 Å, and c parameter values from 5.18 Å to 5.21 Å (values close to typical). The room temperature photoluminescence spectra of the zinc oxide samples showed two main bands: a high energy UV-blue band centred at either 412 or 382 nm (depending on the NH 3 concentration of the leaching solution used), and a green band centred at 527 nm. These emission bands are comparable to those reported for pure zinc oxide. [ABSTRACT FROM AUTHOR]

Copyright of Revista Facultad de Ciencias Basicas is the property of Revista Facultad de Ciencias Basicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Plastics contain various types and amounts of additives that can leach into the water column when entering aquatic ecosystems. Some leached plastic additives are hazardous to marine biota at environmentally relevant concentrations. Disparate methodological approaches have been adopted for toxicity testing of plastic leachates, making comparison difficult. Here we propose a protocol to standardize the methodology to obtain leachates from microplastics (MPs) for aquatic toxicity testing. Literature reviewing and toxicity tests using marine model organisms and different types of MPs were conducted to define the main methodological aspects of the protocol. Acute exposure to leachates from the studied plastics caused negative effects on the early life stages of sea urchins and marine bacteria. We provide recommendations of key factors influencing lixiviation of MPs , such as particle size (<250 μm), solid-to-liquid ratio (1-10 g/L), mixing conditions (1-60 rpm), and lixiviation time (72 h). The proposed methodology was successful to determine the toxicity of leachates from different micronized plastics on marine biota. Our recommendations balance sensitivity, feasibility and environmental relevance, and their use would help ensure comparability amongst studies for a better assessment of the toxicity of plastic leachates on aquatic biota., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Four different alkaline earth metal oxides i.e. MgO, CaO, SrO and BaO were used as heterogeneous catalysts for biodiesel production from palm oil. Effects of critical process variables i.e. reaction time, methanol to oil ratio and temperature were investigated. The results were then fitted to a historical design to study the Analysis of Variance (ANOVA), to characterize interactions between variables and to simulate the process. MgO did not show good catalytic activity while CaO produced undesired products at longer reaction time. BaO showed the best biodiesel result with a yield of up to 95 %, followed by SrO with a yield of 91 %. A methanol to oil ratio of 9:1 and 60 ºC were found to be the optimum conditions. The experimental data were satisfactorily predicted at 99 % confidence level under various conditions with R2 values higher than 0.92. Characterizations of the catalysts before and after the transesterification process were also performed using a surface analyzer, scanning electron microscopy, Hammett indicator and Atomic Absorption Spectrophotometeric (AAS) methods. The catalytic activity was in the order of BaO > SrO > CaO. However, due to lixiviation of BaO in the product, SrO was found to be the most potential catalyst.

Título en ingles: Biooxidation of arsenopyrite concentrates by Acidithiobacillus ferrooxidans in shake flasks Resumen Se evaluó el proceso de biooxidación de concentrados de arsenopirita por A. ferrooxidans ATCC 23270, previa adaptación de los microorganismos al mineral y dos tamaños de partícula, pasante malla Tyler 200 (~75μm) y 325 (~45μm). También, se determinó el grado de concentración del mineral mediante DRX y MOLPP/LR, bajo norma ASTM D 2799 de 2009. Los microorganismos fueron adaptados mediante disminución gradual, en etapas sucesivas, de sulfato ferroso y posterior aumento en el contenido de arsenopirita. Finalmente, se llevó a cabo el proceso de biooxidación del mineral sin adición de Fe2+. Después de treinta días de proceso, la disolución de arsénico para la malla Tyler 200 fue de 7550 mgL-1 (18,7%) y para la malla Tyler 325 fue de 2850 mgL-1 (7,1%). Por otra parte, la curva de crecimiento bacteriano mostró que entre los días 6 y 21 de proceso la población bacteriana promedio fue de 1,70x108 cel.mL‐1 y de 8,00x107 cel.mL‐1 para las mallas Tyler 200 y 325, respectivamente. Por lo tanto, el tamaño de partícula jugó un papel fundamental en la cinética de adaptación de los microorganismos, sugiriendo que a menor tamaño del sustrato empleado mayor dificultad se le presenta al microorganismo para oxidar el mineral. Palabras clave: arsénico; lixiviación; quimiolitótrofos; ATP. Abstract Arsenopyrite biooxidation process was evaluated with A. ferrooxidans ATCC 23270. The microorganisms were previously adapted to mineral and two different Tyler mesh sizes, 200 (~75μm) and 325 (~45μm). Also, the mineral concentration was made by DRX and MOLPP/LR under ASTM D 2799. The microorganisms were adapted through gradual decreasing of ferrous sulphate in successive state and subsequent arsenopyrite concentration increase. Finally, biooxidation process was carried out without Fe2+. After thirty days of process, Arsenic bioleaching was 7550 mgL-1(18,7%) and 2850 mgL-1 (7,1%) for the 200 and 325 Tyler meshes, respectively. On the other hand, bacterial growth curve showed, between 6 and 21 days of process that the average bacterial population was 1,70x108 cel.mL‐1 y de 8,00x107 cel.mL‐1for 200 and 325 Tyler mesh respectively. For this reason, the particle size played an important role in the adaption kinetics of microorganism. The results showed that the microorganism oxide the larger particle size of the mineral easier. Keywords: arsenic; lixiviation; chemolithoautotrophic; ATP.

O objetivo deste trabalho foi avaliar possíveis efeitos da aplicação de taxas de água residuária de suinocultura (ARS), quanto às concentrações de cobre e zinco, tanto no solo quanto na água percolada de lisímetros de drenagem, durante o ciclo da cultura da soja. O experimento foi conduzido em ambiente protegido, onde havia 24 lisímetros de drenagem. Semeou-se soja cultivar CD 202, e foram aplicadas ARS nas seguintes dosagens: 0; 100; 200 e 300 m³ ha-1 no ciclo, combinadas com duas adubações na semeadura (com e sem adição da adubação recomendada na semeadura), em três repetições por tratamento. Foram feitas seis coletas do material percolado durante o ciclo da cultura e realizadas determinações de cobre e zinco. No solo, foram feitas três coletas em cada parcela experimental, para a determinação do pH, da matéria orgânica, da capacidade de troca catiônica, do cobre e do zinco. O delineamento foi em blocos casualizados, num esquema fatorial de 4 x 2. Observou-se que o cobre no solo não apresentou diferenças significativas com a aplicação de ARS e adubação, enquanto as concentrações de zinco no solo foram influenciadas pelas taxas aplicadas de ARS. As transferências de cobre e de zinco por percolação foram pouco expressivas.The objective of this paper is to evaluate the possible effects of applying different rates of swine wastewater (ARS), when it comes to the concentration of copper and zinc and in the percolated water of drainage lysimeters on the soil cultivated with soybeans. The experiment was conducted in a protected environment containing 24 drainage lysimeters. Cultivar CD 202 was sowed and swine wastewater was applied in the following dosages: 0, 100, 200, and 300 m³ ha-1 during the cycle, combined with two fertilizing at sewing (with and without added fertilizing recommended at sewing), in three repetitions per treatment. It was accomplished six collections of percolated material during the crop cycle and it was determinate both copper and zinc. In soil, three collections were accomplished in each experimental plot to determine the pH, organic matter, cationic exchange capacity, copper and zinc. The experiment delimitation was carried out in random blocks in a 4 x 2 factorial scheme. It was observed that copper did not present differences in the application of ARS and fertilizer, while the concentration of zinc on the soil was influenced by rates of ARS Copper and zinc transfer per lixiviation was not meaningful.

Adaptation of agricultural practices according to requirements of the Nitrates Directive and validation through nitrates leaching follow up thanks to lysimeters. Since six years nitric nitrogen lixiviation is followed in six fields located in a silty area in Hesbaye (Belgium), mainly dedicated to vegetable crops. Open-field lysimeters are used, with the aim not to impede agricultural operations. These lysimeters allow the quantitative follow-up of the nitrate lixiviation below the root zone. The aims of the project are the setting up of better agricultural practices with regard to water quality on the one hand, and the adjustement of fertilization advice and the assessment of the impacts on yields, nitrogen remainder, and nitrate concentration in the water collected at the bottom of the lysimeter on the other hand. To reach these aims, experimental designs were set up in the parcels equiped with a lysimeter. These designs allow to test the impact of different levels of nitrogen fertilizers. An environmental indicator (APL in French) follow-up allows to make each year a report on the risk of nitrogen lixiviation related to the different objects tested on the subparcels. Finally, individual yields on the different subparcels are quantified to take the economic impact of the agricultural practices modification into account. During this test, the impact of a fertilization level reduction was just observed on the yields during double vegetable growing, only on the second crop. The other tests showed that a reduction of nitrogen fertilization level (in comparison with fertilization advice), and even, in some cases, no fertilization had no impact on yield and crop quality. A reflexion about soil sampling date for nitrogen fertilization advice was also lead.

La acidez de los suelos es uno de los principales factores que limitan la producción de los suelos sulfatados ácidos tropicales, siendo lenta la corrección con cal agrícola y lavado. El trabajo buscó evaluar el efecto de encalamiento y lavado sobre las características químicas: pH, conductividad eléctrica y contenidos de sulfatos, calcio y magnesio en los lixiviados de un suelo sulfatado ácido (isohipertermico typic sulfaquepts), en San Carlos, Córdoba, Colombia. Fueron instalados lisímetros de 15cm de diámetro x 80cm de altura, rellenados con suelo muestreado en los horizontes superficiales (0-20 y 20 - 40cm), corregidas con dosis de cal de 0, 2, 4, 6, 8 y 10t/ha y lavado con 15L de agua, equivalentes a tres volúmenes de poros. Se utilizó un diseño completamente al azar con cuatro repeticiones, en casa de vegetación de la Universidad de Córdoba. Las variables evaluadas fueron pH, conductividad eléctrica (CE), sulfatos, calcio y magnesio en los lixiviados. El encalamiento aumentó poco el pH; de igual forma, se encontró reducción en la CE y los tratamientos de cal y lavado no incrementaron la lixiviación de sulfatos, calcio y magnesio. Fueron obtenidas ecuaciones de regresión que permitieron estimar, aproximadamente, 10t/ha de cal, para elevar el pH a 5 y reducir la CE a 2dS/m.Soil acidity is on of the main factors which limit production of tropical acid sulfate soils, being the correction with liming and washing slow. The aim of this research was to evaluate the effect of liming and washing on the chemical characteristics, pH, electric conductivity, sulfates, calcium and magnesium content of lixiviates in an acid sulfate soil (franc isohipertermico typic sulfaquepts) from San Carlos, Córdoba, Colombia. Lysimeters, 15cm of diameter x 80cm of height were installed, and filled with soil collected from the surface horizon, 0 -20 and 20 - 40cm, limed with 0, 2, 4, 6, 8 and 10t/ha, and washed with 15L of water, equivalent to three pore volumens. The research was carried out with a randomized block design with four replications, in a hothouse of the University of Córdoba, Colombia. The evaluated variables were pH, electrical conductivity (EC), sulfates, calcium and magnesium contents in the leaching. A small increase in pH due to liming was detected, as well as a reduction in EC; however, liming and washing did not increase the lixivation of sulfates, calcium and magnesium. Regressions models were obtained, which permitted to, approximately, estimate 10t/ha lime to increase pH to 5 and to reduce EC to 2dS/m.

Con el propósito de evaluar formalmente los potenciales cambios producidos en el carbón mineral debido a su interacción con agua de lago de Maracaibo ADL, así como determinar las características de riesgo ambiental y toxicidad del mismo. Dos muestras de carbón mineral del Pit Miraflores del yacimiento Mina Norte, Cuenca del Guasare, Estado de Zulia, Venezuela, fueron sometidas a procesos de lixiviación con fluido de extracción # 1 conjuntamente se realizó la lixiviación con ADL, durante 4, 6, 18, 48 y 72 horas, finalmente se ejecutaron bioensayos de toxicidad aguda. Las muestras de carbón y los fluidos (ADL y fluido extractor # 1) fueron caracterizados químicamente antes y después de los procesos de lixiviación, lo cual incluyó: azufre total, análisis próximo (CF de carbón fijo, Contenido de Humedad, Materia Volátil MV y Ceniza Cz) en el carbón, sulfatos, aceites y grasas, pH, aluminio intercambiable, cloruro, % saturación con bases, conductividad, relación de absorción de sodio y Ba, Cd, Hg, Se, Ag, Cr, Ni, Zn y Pb. Los resultados indican que los carbones estudiados son térmicamente inmaduros y se clasifican como bituminosos altos en volátiles. Las variables Carbono Fijo (CF), Humedad (Hum), Materia Volátil (MV) y Cenizas (Cz), se mantienen esencialmente constantes a lo largo de todo el proceso de lixiviación de los carbones; y la concentración de azufre total (St) varía a lo largo del proceso de lixiviación. En una de las muestras (alta concentración de cenizas Cz) el azufre es lixiviado mientras que en la muestra de bajo contenido de Cz, la masa de azufre en el carbón aumenta posiblemente por procesos de adsorción de iones provenientes del ADL. Los resultados obtenidos no demuestran evidencia de algún potencial de contaminación a corto o largo plazo por elementos potencialmente tóxicos. Atendiendo a las características observadas en el presente estudio, la condición de riesgo de los carbones bajo estudio es de clase 1 (Decreto 2635). Las muestras estudiadas tienen una toxicidad relativamente baja y la muestra Coal 1 resulta ser relativamente más tóxica que la muestra Coal 2.In order to evaluate formally the potential changes produced in the coal due to its interaction with Maracaibo lake water and determine the characteristics of environmental risk and toxicity of coal from Miraflores pit of Mina Norte coalfield, Guasare Basin, Zulia State, Venezuela. Two coal samples were subjected to mandatory EPA toxicity leaching procedure with extracting solution #1, beside leaching procedure with Maracaibo lake water ADL, during 4, 6, 18, 48 and 72 hours, finally acute toxicity bioassays were done; coals and fluids were chemically characterized before and after leaching processes, those include: total sulphur, proximate analysis (Fixed Carbon CF, Humidity Hum, Volatile Matter MV and Ash Cz) of coal, sulphates, oil and grease, pH, aluminum interchangeable, chloride, base saturation, conductivity, sodium absortion ratio SAR and As, Ba, Cd, Hg, Se, Ag, Cr, Ni, Zn y Pb. The results indicate that the studied coals are thermally immature and they are classified as high volatile bituminous. During the process of leaching, Fixed Carbon (CF), Humidity (Hum), Volatile Matter (MV) and Ash (Cz) parameters stay essentially constant; while total sulfur concentration (St) varies along the leaching process. In one of the samples (high concentration of ash Cz) the sulfur is leached while in the sample of low ash content the mass of sulfur in the coal increases. Results obtained do not show evidence of short and long term pollution potential by bioavailable toxic elements. According to the characteristics observed in the present study, the risk condition of the Guasare coal is class 1. The studied samples have a relatively low toxicity, and the Coal 1 sample seem to be relatively more toxic than the Coal 2 sample.

An accurate and sensitive method for the determination of selected EDCs in soil and compost from wastewater treatment plants is developed and validated. Five parabens, six benzophenone-UV filters and the antibacterials triclosan and triclocarban were selected as target analytes. The parameters for ultrasound-assisted extraction were thoroughly optimized. After extraction, the analytes were detected and quantified using ultra-high performance liquid chromatography tandem mass spectrometry. Ethylparaben (ring– 13 C 6 labelled) and deuterated benzophenone (BP-d 10 ) were used as internal standards. The method was validated using matrix–matched calibration and recovery assays with spiked samples. The limits of detection ranged from 0.03 to 0.40 ng g −1 and the limits of quantification from 0.1 to 1.0 ng g −1 , while precision in terms of relative standard deviation was between 9% and 21%. Recovery rates ranged from 83% to 107%. The validated method was applied for the study of the behavior of the selected compounds in agricultural soils treated and un-treated with compost from WWTP. A lixiviation study was developed in both agricultural soil and treated soil and first order kinetic models of their disappearance at different depths are proposed. The application of organic composts in the soil leads to an increase of the disappearance rate of the studied compounds. The lixiviation study also shows the risk of pollution of groundwater aquifers after disposal or waste of these EDCs in agricultural soils is not high. [ABSTRACT FROM AUTHOR]

Average annual precipitation (AAP) is one of the principal environmental factors that regulates processes in terrestrial ecosystems. The effect of AAP on the availability of edaphic nutrients is poorly understood, especially in tropical zones with high rainfall. In order to evaluate the effects of high AAP on the availability of soil N, P, and K, physicochemical parameters were measured in soils of three tropical rainforests in the Chocó biogeographical region with different AAPs (7,500, 8,000, and 10,000 mm yr-1). Furthermore, a bibliographical review was carried out that including studies for distinct tropical Ultisols and AAP ranging from 1,800 to 10,000 mm yr-1. The evaluated soils presented extreme acidity with high contents of Al, organic matter (OM) and total N, and low quantities of P, Mg, and Ca. The K concentrations were intermediate and the effective cation exchange capacity (ECEC) was low. On the other hand, in the evaluation of the influence of the AAP on the availability of N, P, and K in the soil, contrasting tendencies were observed. On one side, a positive curvilinear relationship was found between the availability of N and the increase in the AAP. On the other side, the available P content significantly decreased with increasing AAP. In conclusion, the excessive AAP resulted in increases in total N and low availability of P, thereby altering the dynamics of the nutrients and the carbon balance of the tropical forest. [ABSTRACT FROM AUTHOR]

O objetivo do experimento foi avaliar a eficiência da adubação nitrogenada na forma de uréia, em pastagem de triticale mais azevém, submetida a pastejo com lotação contínua. Foram usados quatro níveis de nitrogênio em cobertura: 0, 150, 300 e 450 kg N/ha, divididos em cinco aplicações. A massa de forragem disponível foi de 1404, 1437, 1619 e 1599 kg MS/ha, respectivamente. A produção total de forragem foi de 6039, 6914, 7877 e 7662 kg MS/ha e a produção de nitrogênio, de 191,6; 247,7; 303,2 e 307,2 kg/ha, para os níveis 0, 150, 300 e 450 kg N/ha, respectivamente. A eficiência da adubação nitrogenada foi de 5,83; 6,13; e 3,61 kg MS/kg de nitrogênio aplicado e a recuperação de nitrogênio, de 37,39; 37,21 e 25,69%, para os níveis 150, 300 e 450 kg N/ha, respectivamente. Na avaliação da concentração de nitrogênio nas camadas do perfil do solo (0-5, 5-10, 10-20 e 20-40 cm de profundidade), em duas datas (20/07 e 20/09), constatou-se aumento no teor de nitrogênio mineral, da primeira para a segunda avaliação, principalmente nas maiores profundidades e nos maiores níveis de nitrogênio, indicando que houve perdas por lixiviação, diminuindo a recuperação e eficiência no uso deste nutriente.The objective of this experiment was to evaluate the nitrogen fertilization efficiency using urea, on triticale plus Italian ryegrass pasture, submitted to continuous stocking. Four nitrogen levels were used: 0, 150, 300 and 450 kg of N/ha, divided in five applications. The herbage mass was 1404, 1437, 1619 and 1599 kg of DM/ha. The total herbage production was 6039, 6914, 7877 and 7662 kg of DM/ha and the nitrogen production was 191.6, 247.7, 303.2 and 307.2 kg of N/ha for the 0, 150, 300 and 450 kg of N/ha levels, respectively. The nitrogen fertilization efficiency was 5.83, 6.13 and 3.61 kg of DM produced/kg of nitrogen applied and the nitrogen recovery was 37.39, 37.21 and 25.69% for the levels of 150, 300 and 450 kg of N/ha, respectively. The nitrogen concentration in different depth of the soil profile (0-5, 5-10, 10-20 and 20-40 cm of depth) in two dates (07/20 and 09/20) was evaluated. An increase of the mineral nitrogen content, from the first to the second evaluation, mainly for the deepest layers and for the highest nitrogen levels was observed, indicating that lixiviation losses of nitrogen occured, reducing the nitrogen recovery and his efficiency