Oil pollution caused by heavy shipping traffic in the Baltic Sea could be removed by the help of highly porous aerogels made from the waste. These could be produced from environmentally friendly cellulose, e.g., from paper waste, but would have to be hydrophobized for oil sorption. Such a cellulose aerogel was investigated in this research work. Six types of aerogel with 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 wt% cellulose with porosities in the range of 96–98% stabilized by unsaturated polyester as cross-linker have been produced. Aerogel’s sorption capacity as well as its regeneration for sorption of crude oil, marine diesel oil, and biodiesel sorption from water surface and mechanical strength has been estimated. It was found out that crude oil sorption capacity reach 29.67 ± 0.39 g g⁻¹, biodiesel—29.07 ± 0.26 g g⁻¹, while marine diesel oil—26.26 ± 0.39 g g⁻¹. The aerogel with 0.5 wt% cellulose shows the best sorption properties after 10 cycles of the sorption.

A heterotrophic nitrification-aerobic denitrification (HN-AD) mixed culture was established as a simulated aquatic ecosystem to investigate the simultaneous removal of aniline and ammonium, as well as the succession of bacterial community. Aniline and ammonium were found to be simultaneously transformed, with maximum removal efficiencies of 99.98% and 89.87%, respectively. The presence of aniline at lower concentrations (0 to 100 mg/L) slightly inhibited ammonium oxidation, whereas further increasing the aniline concentration (from 100 to 500 mg/L) yielded an apparent enhancement effect, increasing the ammonium-N removal rate from 0.33 to 1.26 mg/L/day. In contrast, ammonium-N concentrations of 100 mg/L were able to facilitate aniline removal. Ammonium was the preferred nitrogen source for aniline removal when compared with nitrification metabolites such as nitrate or nitrite. The analysis of microbial community succession using high-throughput sequencing revealed that the microbial diversity generally decreased throughout the aniline and ammonium removal process. Proteobacteria is observed to increase at the climax stage, and the average relative abundances of Pseudomonas, Massilia, and Bacillus were highest at the climax stage and were positively related to the removal rate of aniline and ammonium-N. Surprisingly, the abundance of these microbes at the end stage was almost equal to that observed at the initial stage. This study demonstrated that polluted aquatic ecosystems hold potential for simultaneous removal of pollutants (hazardous organic carbon and ammonium), and have excellent self-rehabilitation abilities.

Chloramination of drinking water and wastewater can generate carcinogenic nitrosamines, among which, nitrosodipropylamine (NDPA) with large molecular weight and weak polarity has been commonly found. However, knowledge on the formation of NDPA remains highly limited. Laboratory tests were conducted to quantify NDPA formation during chloramination of nitrogenous precursors, including dipropylamine and methyldipropylamine, and pesticides such as trifluralin, oryzalin, and vernolat. Results showed that all precursors exhibited > 10.0% NDPA yields after 24 h. Oryzalin and trifluralin accomplished the highest (13.63%) and lowest (11.31%) yield, respectively. Maximal yields of all precursors were observed at pH 9.0 and temperature 288 K. Maximums of NDPA yield from oryzalin (18.27%) and vernolat (19.54%) were formed at Cl:N of 0.7:1.0, but maximal yields of dipropylamine (18.44%), methyldipropylamine (22.98%), and trifluralin (33.06%) were achieved at Cl:N of 1.2:1.0. Maximal NDPA yields of dipropylamine (37.14%), methyldipropylamine (32.84%), and vernolat (49.02%) were observed at [NH₂Cl]₀:[precursor]₀ = 500, but highest yields of trifluralin (30.24%) and oryzalin (25.53%) were accomplished at [NH₂Cl]₀:[precursor]₀ = 50. Bromide and organic contents in tap and raw water reduced NDPA due to competition for NH₂Cl. Chloramination of water impacted by amines and pesticides should be careful of NDPA formation.

In the search for alternatives to bioremediation of soils, this research aimed to analyze the effects of lime, cement, and asphalt as stabilizers on clayey gravel and sand soil contaminated with gasoline in the laboratory. Concentrations of 10–20% of lime, cement, and asphalt were added to the soil. A standard sample was chosen to compare the results obtained in the modified Proctor compaction, California bearing ratio (CBR), direct shear, and consolidation tests. It was found that the presence of more than 10% liquid low–density hydrocarbon affects plasticity, void ratio, friction angle, moisture content, dry density, and cohesion. According to the tests carried out, soils contaminated with concentrations lower than 10% of gasoline are recommended to construct the subgrade and sub-base layers in pavements. Finally, it was found that cement is the stabilizer that presented overall higher enhancements of the mechanical properties of the clayey gravel and sand soil among the three stabilizers. However, the results also show that depending on the soil use and specific parameter requirements, other stabilizers can be used.

In this work, earthworm effect on the efficiency of biobeds for glyphosate degradation was studied. Three biomixtures with and without the addition of earthworms (Eisenia fetida species) were evaluated. The initial concentration of glyphosate was 1000 mg/kg biomixture. Glyphosate and biological parameters were measured as a function of time. Earthworm survival, biomass, and reproduction were evaluated as well. All biomixtures that contain earthworms reached 90% of glyphosate degradation at 90 days in comparison with the biomixtures without earthworms that reached 80% approximately at the same time. Also, within the biomixtures that contained earthworms, glyphosate degradation rate was significantly higher in the one made up with soil and wheat stubble (Ws-E) showing excellent capacity for aminomethylphosphonic acid (AMPA) degradation, the main metabolite of glyphosate degradation. In addition, a study performed after the vermiremediation process showed that E. fetida can tolerate high glyphosate concentration without modifications in its life traits. It can be concluded that the use of E. fetida within the biobeds is an excellent combination to improve glyphosate and AMPA removal.

The naproxen adsorption capacity enhancement of activated carbon prepared from the Indian gooseberry seed-shells by manufacturing a composite blended with the surface-modified graphite powder and silver nanoparticles was studied in the present context. The composite of the nano-sized materials was prepared in dimethylformamide solution and characterized by employing XRD, Raman, EDS and FT-IR spectroscopy, FETEM, and FESEM microscopy. The pseudo-first-order, pseudo-second-order, and Elovich models were applied to test the removal kinetics. Preliminary results were also fitted to the Langmuir, Freundlich, Temkin, and Dubinine-Radushkevich (D-R) adsorption isotherm models to determine the specific parameters of each model. The effects of the initial pH of the solution, naproxen concentration, and contact time on the process were optimized. The maximum adsorption capacity was obtained as 154.98 mg g⁻¹ (61.99%) with an increment of 25.31% by the addition of surface-modified graphite powder and silver nanoparticles at the optimized experimental conditions.

In recent years, the problem of rising salinity levels in the Shatt al-Arab river in southern Iraq has been repeated, which has directly affected the living and health situation and the agricultural activity of these areas. Six sampling stations were selected along Shatt al-Arab to estimate the concentration of total dissolved solids (TDS) in the river; these stations included the following: Qurna, Labani, City Centre, Kateban, Corniche, and Sihan. In addition, three Landsat-8 satellite images which were taken at the same time as collected samples also used for detecting the salinity in the river. After processing of atmospheric correction and inserted remote sensing indices, the reflectance of water extracted from satellite images was used to express the spectral characteristics of different TDS concentrations. Correlation and regression were used to obtain accurate models for detecting the salinity depending on the spectral reflectance of Landsat 8 operational land image OLI. The results presented Pearson correlation (r) value of 0.70, 0.97, and 0.71, and correlation coefficient (R²) of 0.56, 0.94, and 0.85 between field data with spectral data of salinity index 2 (SI-2) derived from the green and blue bands of Landsat obtained in 2015, 2017, and 2018 respectively. In conclusion, remote sensing and GIS technologies coupled with spectral modeling are useful tools for providing a solution of future water resources planning and management, and also offer great undertaking as a means to improve knowledge of water quality and support water decision making.

The uptake of organic pollutants by agricultural plants and their accumulation in edible parts cause serious health problems to animals and humans. In this study, we used carbon-rich materials, such as biochar (BC), hydrochar (HC), and green compost (GC), to reduce the absorption and accumulation of three pesticides, imidacloprid (IMI), boscalid (BOS), and metribuzin (MET) and two endocrine disruptors, 4-tert-octylphenol (OP) and bisphenol A (BPA), in rocket salad plants (Eruca vesicaria L.). After an experimental period of 35 days, compared to unamended soil, the addition of BC, HC, and GC significantly reduced chemical phytotoxicity, increasing the elongation of the aerial plant parts by 26, 25, and 39%, respectively, whereas GC increased the fresh biomass by 21%. The assessment of residual chemicals in both soil and plant tissues indicated that any amendment was very effective in enhancing the retention of all compounds in soil, thus reducing their uptake by plants. Averagely for the five compounds, the reduction of plant absorption followed the trend BC > HC > GC. In particular, the presence of BC decreased the chemical residues in the plants from a minimum of 71% (IMI) to a maximum of 91% (OP). The overall results obtained encourage the incorporation in soil of C-rich materials, especially BC, to protect leafy food plants from the absorption and toxicity of organic pollutants of a wide range of hydrophobicity, with relevant benefits for consumers.

The accumulation of ammonia and nitrite in natural water and aquaculture systems would suppresses the immune system of aquatic animal and reduces the fish growth. Nitrifying bacteria have been widely used to reduce the accumulation of ammonia and nitrite in aquaculture systems, but are still ineffective in many cases. An aquaculture model system consisting of red crucian carp, algae, nitrifying bacteria, and pond water from a natural fish culture was established to explore the limitation of algae and light to nitrifying bacteria content and bacterial nitrification in the presence of a predator. The concentrations of nitrifying bacteria and bacterial nitrification in the group containing algae and light were significantly limited, and addition of nitrifying bacteria in algae groups had little effect. In algae-free groups, the concentrations of ammonia and nitrite were decreased by nitrifying bacteria, and the potential ammonia oxidization rate was also increased. Our findings reveal that the combined effects of algae growth and light exposure are responsible for the observed ineffectiveness of nitrifying bacteria in natural aquaculture environments.

Bisphenol A (BPA) can potentially trigger hormonal imbalances and affect aquatic species when discharged untreated into the ecosystems. This study explored the influencing factors, mechanism, and pathways of BPA degradation process in aqueous solution applying strong ionization discharge (SID) method. The results elaborate that 99.5% degradation rate was achieved in 60 min when 15 mg L⁻¹ BPA solution was treated applying 3.74 kW of input power. Weak alkaline conditions were favorable to BPA removal in SID system. In addition, the inhibition of radical scavengers on the SID process laterally verified the presence of hydroxyl radicals (HO·) in the oxidation process besides ozone (O₃). What is more, the addition of 15 mg L⁻¹ sodium percarbonate (SPC) can improve 6.93% degradation rate of 30 mg L⁻¹ BPA based on the SID system. Furthermore, ultraviolet-visible spectroscopy (UV-vis), high-performance liquid chromatography (HPLC), total organic carbon (TOC), and chemical oxygen demand (COD) analysis were conducted to measure the capacity of SID system for BPA treatment. The molecular analysis via liquid chromatography-mass spectrometer (LC-MS) and gas chromatography-mass spectrometer (GC-MS) showed that a portion of the intermediates in BPA degradation process were characterized by 3,4-dihydroxybenzoic acid, o-xylene, p-xylene, and propane-1,2,3-triol, etc., which were ultimately mineralized into CO₂ and H₂O. Based on the above analysis, the SID oxidation mechanism and pathways were proposed.