Offshore oil spills are a critical form of marine pollution, requiring researchers to mitigate their impacts. In this sense, this paper contributes to a better understanding of oil behavior after spillage and the improvement of contingency measures. Using Bacia de Campos as the study area, which accounts for approximately 32% of daily oil and gas production in Brazil, information regarding the properties of light, medium, and heavy oils, seawater, wind and wave weather conditions, and oil spill characteristics was used to perform simulations to identify the percentage of oil remaining after the offshore spill and the effectiveness of the chemical dispersant in dispersing this oil. The results show that after the weathering simulation, on average, 55% of the spilled oil remains at sea in dispersed and remaining form and that the use of chemical dispersant under the conditions defined in this study did not result in significant oil removal.

Although environment protection efforts worldwide, the chemistry and biological contamination of waters represents an important challenge to be overcome, especially regarding its contamination by domestic wastewater effluents. In this context, this research presented an analysis by using an innovative wastewater treatment system for domestic effluents based on the electro-oxycoagulation approach implanted in wastewater treatment station located at Palma Sola, Santa Catarina, Brazil. We evaluated samples from domestic effluent (before and after treatment), fountain water, and river water collected from the municipality water system, as well as investigated the residual compound yielded by wastewater treatment. In these samples, we performed physicochemical analysis, investigation of viable helminth eggs, and toxicity and microbiological measurements before and after the treatment. Further, the levels of contaminant metals by X-ray fluorescence-based technique were analyzed. Results show an improvement in the quality of treated water, as demonstrated by microbiological, physicochemical, toxicity, and metal analysis of effluent after treatment. After treatment, river water and fountain water levels of metals in accordance with the maximum limits allowed by Brazilian regulatory agencies. Analysis of residual compound indicated that the workers that handle the residue were not contaminated with the identified metals. Thus, the electro-oxycoagulation-based method demonstrated high efficiency for the treatment of domestic effluents and further prevents contamination of the rivers by the released effluent without treatment.

In our research, thiolated reduced graphene oxide aerogels (TrGOAs) was successfully prepared by using graphene oxide (GO) as precursor and sodium hydrosulfide (NaSH) as reductant via a one-pot one-step hydrothermal route under normal pressure and a subsequent freeze-drying, used as a novel carbon-based adsorptive material for adsorbing Cu(II) ions from deionized water. These aerogels show excellent adsorption ability towards Cu(II) ions, which have a huge adsorption amount around 421.21 mg·g⁻¹. We studied the mechanism of the adsorption process of TrGOA-5, and the results found that the pseudo-second-order kinetic model and the Freundlich isotherm model were able to describe this process well. We also explored the interference of pH values in copper ion solutions during this adsorption process, suggesting that increasing pH is good for obtaining a higher adsorption capacity. In addition, solid-liquid separation can be readily realized by filtration and centrifugation after the end of the adsorption experiment. Overall, this research offers a relatively simple and cut-price strategy to obtain thiolated reduced graphene oxide aerogels, and these novel graphene-based adsorbents have a superior adsorption ability and recyclability in segregating copper ions from polluted water.

Olive oil industry generates a considerable amount of olive mill wastewater (OMW) each year, which increases the difficulties for successful processing and disposing. A possible and potential alternative is controlled application of OMW into the land. In these two fields’ experiments, we investigated a sustainable controlled land application of OMW to enhance soil properties and improve barley production under rainfed conditions. OMW was spread at five application rates (20, 40, 60, 80, and 120 m³ ha⁻¹) in addition to the control at two sites, Rabba and Ghweer. The physicochemical characterizations of OMW were determined throughout the season. Physicochemical properties of soil were measured after 2 weeks of OMW spreading after planting and after barley harvest. Leaf nutrient content as well as other growth performance has been measured. The results of this study showed no harmful effect of OMW application for all application rates on growth parameters of barley as well as soil properties at both locations. Under all application rates, OMW has increased soil organic matter and nutrient contents, which could reduce the use of chemical fertilizer. There was a significant increase in barley growth in OMW treatments for dry weight (DM) (14 and 22%), biological yield (BYLD) (49 and 34%), grain yield (GYLD) (41 and 47%), and straw yield (SYLD) (55 and 31%) at Rabba and Ghweer sites, respectively. The results exhibited the benefit of controlled application of OMW. However, long-term effect of OMW application needs more study, and local legislative is necessary.

The cobalt ferrite loaded on multi-walled carbon nanotubes (MWCNTs-CoFe₂O₄) was synthesized and used as a novel catalyst for the degradation of mefenamic acid (MFA) in the presence of peroxymonosulfate (PMS). The results showed that MWCNTs-CoFe₂O₄ has higher catalytic performance in the activation of PMS and degradation of MFA compared with MWCNTs, Co²⁺, Fe²⁺, and CoFe₂O₄. The highest kinetic constant rate (0.0198 min⁻¹) and MFA degradation (97.63%) were obtained at pH = 7, PMS = 4 mM, catalyst = 500 mg/L, MFA = 10 mg/L, and time = 150 min. MFA degradation accelerated with increasing PMS and catalyst dosage but decreased by initial pH. The influence of different anions and water matrix on the catalytic system was investigated, and the results explained a decrease in the MFA rate in the presence of the interfering substances. Scavenging experiments showed that both sulfate radical anion (SO₄•⁻) and hydroxyl radical (•OH) were effective on MFA degradation, but SO₄•⁻ had a greater effect on the degradation of MFA. In addition, the stability and recyclability of MWCNTs-CoFe₂O₄ were evaluated in the consecutive reaction cycle; the MFA degradation rate reached 89.75% after 4 cycles of reaction. The MFA degradation products were identified by gas chromatography-mass spectrometry (GC-MS) and their degradation pathway was suggested. Finally, a comparison was conducted among the methods used for PMS activation, and the results showed that the cobalt ferrite-based catalyst has high degradation efficiency. However, ultrasound, heat, and ultraviolet (UV) processes can be used to improve the degradation rate of the MWCNTs-CoFe₂O₄/PMS system at different reaction times.

Rapid growth of vehicles in Medan, Indonesia, is one of the causes in the increasing of air pollution, in which approximately 85% is contributed merely by vehicles. On the other hand, the use of lead-based fuel in motor vehicle increases the air contamination in Medan. This study aimed to obtain an accumulation of lead (Pb) in the thallus of lichens in mahogany trees in four different locations in Medan, Sumatera Utara, Indonesia, in which the lichens act as a bioindicator of air contamination as well as measuring the lichen’s lead correlation and traffic densities. Purposive sampling location was determined based on the traffic density level with different air pollutions; the location which was far from traffic circulation was used as the control. The analysis of Pb was conducted using atomic absorption spectrophotometry (AAS). The data were analyzed descriptively to discover and compare Pb accumulation between each location with different traffic density levels. The result showed that there were 11 species of 7 genera and 7 families with two types of the thallus (foliose and crustose) in mahogany trees. The traffic density level influenced the diversity of lichens as the traffic density was quite significant with the number of lichen types. The levels of Pb and traffic density correlated very significantly at the level of α = 0.01 for Parmelia saxatilis, Lepraria incana, and Pertusaria amara type, while Opegrapha atra had a significant correlation. The accumulation of Pb in the thallus of Pertusaria amara ranged from 5.23 to 15.07 μg/g, whereas medium in Lepraria incana ranged from 1.19 to 4.88 μg/g. Thus, Pertusaria amara which had greater Pb level than Lepraria incana had the potential as a resistant bioindicator. The correlation analysis of Pb levels and traffic density showed that Pertusaria amara had a significantly high correlation compared with Parmelia plumbea, Parmelia glabratula, and Graphis scripta. Furthermore, Lecanora conizaeoides was a tolerant bioindicator of air pollution whereas Parmelia saxatilis had the potential to be a tolerant bioindicator.

Biological methods offer eco-friendly and cost-effective alternatives for the synthesis of silver nanoparticles (AgNPs). The present study highlights a green process where AgNPs were synthesized and optimized by using silver nitrate (AgNO₃) and the aqueous extract of Piper betle (Pbet) leaf as the reducing and capping agent. The stable and optimized process for the synthesis of Pbet-AgNPs was exposure of reaction mixture into the sunlight for 40 min, pH 9.0, and 2 mM AgNO₃ using 1:4 diluted Pbet leaf aqueous extract. The optimized Pbet-AgNPs were characterized by UV–visible spectroscopy, high-resolution field emission scanning electron microscopy (FE-SEM), X-ray diffractometry (XRD), and Fourier-transform infrared spectroscopy (FTIR). The prepared Pbet-AgNPs were spherical in shape with size in the range of 6–14 nm. These nanoparticles were stable for 6 months in aqueous solution at room temperature under dark conditions. The biogenic synthesized Pbet-AgNPs are found to have significant antifungal activity against plant pathogenic fungi, Alternaria brassicae and Fusarium solani. Synthesized Pbet-AgNPs potentially reduced the fungal growth in a dose-dependent manner. Microscopic observation of treated mycelium showed that Pbet-AgNPs could disrupt the mycelium cell wall and induce cellular permeability. Protein leakage assay supports these findings. Overall, this study revealed the efficacy of green synthesized AgNPs to control the plant fungal pathogens. Pbet leaves are a rich source of phenolic biomolecule(s). It was hypothesized that these biomolecule(s) mediated metal reduction reactions. In this context, the present work investigates the phytobiomolecule(s) of the aqueous extract of Pbet leaves using high-resolution liquid chromatography–mass spectroscopy (HR-LCMS) method. The analysis revealed that eugenol, chavicol, and hydroxychavicol were present in the Pbet aqueous extract.

A biosurfactant (BS) is a surface-active metabolite that is secreted by microbial metabolism, and can be used as a substitute for chemically synthesized surfactants. The first and most critical step to the successful application of BSs is to isolate bacterial strains with strong BS-producing capabilities. In this study, a BS-producing Serratia marcescens ZCF25 was isolated from the sludge of an oil tanker. Through polyphasic characterization using Fourier-transform infrared spectroscopy, thin layer chromatography, and gas chromatography-mass spectrometry, the produced BS was classified as a lipopeptide; it can decrease the water surface tension from 72.0 to 29.50 mN m⁻¹ and has a critical micelle concentration of 220 mg/L. The BS showed a high tolerance over a wide range of pH (2–12), temperature (50–100 °C), and salinity (10–100 g/L). Furthermore, the inoculation of S. marcescens ZCF25 with fracturing flowback fluids could significantly (P < 0.05) reduce the chemical oxygen demand, concentration of alkanes, and concentration of polycyclic aromatic hydrocarbons, with removal efficiencies of 48.9%, 65.57%, and 64%, respectively. This is the first study on the application of BS-producing S. marcescens to treat fracturing flowback fluids. S. marcescens ZCF25 is a promising candidate for use in various industrial and bioremediation applications. Graphical abstract

The aim of this study is to examine the relationship between ecological footprint, economic growth, renewable energy consumption, and innovation within the framework of the environmental Kuznets curve (EKC) hypothesis for the top 10 innovative economies, namely, Denmark, Finland, Germany, Israel, Korea, The Netherlands, Sweden, Switzerland, the UK, and the USA, in the period of 1990–2015. For this purpose, the long-term relationship between variables was examined with a panel cointegration test. The results show that the variables in the EKC model move together in the long run. According to the long-run estimation results, the EKC hypothesis is valid for Israel, but not for the other countries. The study also makes the following observations: (i) For Korea, the USA, Finland, and the whole panel, innovation appears to reduce environmental pollution. (ii) Renewable energy consumption reduces environmental pollution for Denmark, Germany, The Netherlands, and the USA. (iii) Globalization has an impact on the reduction of environmental pollution for Germany and Switzerland. As a result, developing policies on the use of more innovative technologies in the countries studied will have a positive impact on environmental pollution. Graphical abstract

To solve the issues of serious wear, blockage, and poisoning of the catalyst in the denitration process of industrial furnaces such as glass furnaces and cement kiln, it was proposed to integrate the high-temperature dual-layer granular bed filter and the selective catalytic reduction (SCR) reactor into a device to realize the denitration of the SCR catalyst in a dust-free state. In the device, the upper part was a dual-layer granular bed filter and the lower part was a V₂O₅-WO₃/TiO₂ honeycomb ceramic catalyst. In the self-built dust removal and denitration integrated test equipment with an inner diameter of 100 mm, the effects of flue gas temperature, flue gas flow rate, nitric oxide (NO) concentration, and catalyst height on the denitration efficiency of the catalyst were investigated by orthogonal testing under dust-free conditions. The results show that the flue gas flow rate had the greatest influence on the denitration efficiency of the catalyst. With an increase in flue gas flow rate, the denitration efficiency first increased and then decreased. When the flue gas flow rate was 0.3 m/s, the denitration efficiency reached a maximum. The denitration test was carried out using flue gas with a dust concentration of 15 g/m³. The results show that the denitration efficiency continued to decrease with the deposition of dust on the catalyst surface (from an initial value of 96.51 to 80.59% at the 140th min), and the pressure drop correspondingly increased from 100 to 630 Pa. Additional integration testing of dust removal and denitration showed that the average dust removal efficiency of the integrated device for dust removal and denitration using a dual-layer granular bed filter could reach 99.84%, and the average denitration efficiency could reach 95.07%.