Changes in crude oil production and distribution have increased the incidence of oil spills throughout the world. Oil spills often cause destructive effects on aquatic and land ecosystems. The oil spill cleanup and recovery techniques are challenging and usually involve complex mechanical, chemical, and biological methods. Usually, mechanical removal of free oil is utilized as an effective strategy for cleanup in aquatic and terrestrial environments; however, they are expensive and need specialist personnel and equipment. The other commonly used method is the application of chemical materials such as dispersants, cleaners, demulsifiers, biosurfactants, and soil oxidizers. Nevertheless, these reagents can have potential harmful environmental impacts, which may limit their application. As an alternative, bioremediation can offer reduced environment risk; however, the limitations of microbial activity in the soil can make this option unsuitable. One area of bioremediation is phytoremediation, which offers potential for restoring large areas of contaminated ground. Plants are able to remove pollutants through processes such as biodegradation, phytovolatilization, accumulation, and metabolic transformation. This review presents the fate of crude oil spills in aquatic and land ecosystems and their environmental effects. Furthermore, the paper focuses on crude oil phytoremediation and its applications in polluted ecosystems.

Mg, Zn, Mn, and Al oxide powders have been synthesized through chemical combustion and calcination methods to compare their CO₂ capture performances. The characteristic properties of the adsorbents were evaluated by X-ray diffraction analysis, scanning electron microscopy, and N₂ physisorption measurements. The porous γ-Al₂O₃ prepared through combustion with a BET-specific surface area of 192.1 m²/g, achieving a maximum gas adsorption capacity of 1.71 mmol/g at 60 °C and 1.5 MPa. The MgO adsorbent performed poorly during CO₂ capture, while that Zn and Mn oxides showed no CO₂ adsorption. The results showed theoretical contribution to the field of separation science.

The novel titanium oxide/active carbon fiber (TiO₂/ACF) electrode was prepared, and electrosorptive properties for As(V) in aqueous solution were investigated. The structure of TiO₂/ACF was characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Furthermore, the As(V) electrosorptive properties of TiO₂/ACF electrodes with calcination temperature, ionic species, and loaded amount of TiO₂ were measured, and the electrosorption isotherm and kinetics were investigated at the applied voltage of 1.5 V. The optimal load quality of TiO₂ was 0.80 g per ACF electrode (length × width × height = 2 cm × 1 cm × 0.4 cm, 0.30 g), and optimum calcination temperature was 450 °C. The maximum electrosorption capacity of TiO₂/ACF was 8.09 mg/g, about 200 % higher than that of ACF. Moreover, the electrode performance was stable than other materials such as pure ACF, manganese oxide/ACF, and iron oxides/ACF. It can process 100 ppb As(V) of water to 6 ppb (reach the drinking water standards of WHO), demonstrating that our novel electrode is with potential practical application.

A novel cerium-loaded cellulose nanocomposite bead (CCNB) is synthesized and tested for fluoride adsorption. The optimization of the process under the cooperative influence of different experimental variables was made employing response surface methodology (RSM). It is found from fractional factorial design (FFD) that among the different experimental variables, only adsorbent dose, temperature, and pH are significant. At the optimum condition (adsorbent dose 1 g L⁻¹, temperature 313 K, pH 3.0), a maximum fluoride adsorption of 94 % was observed for an initial fluoride concentration of 2.5 mg L⁻¹. A quadratic polynomial model equation based on central composite design (CCD) was built to predict the extent of adsorption. The result of the analysis of variance (ANOVA) shows high coefficients of determination (correlation coefficient; R² = 0.9772, adjusted R² = 0.9545, and adequate precision = 18.1045) and low probability value (Prob > F, 0.001) which signifies the validity of the model. The equilibrium adsorption data conformed to the Tempkin isotherm, having higher R²and lower SE value, among the Langmuir, Freundlich, and Tempkin equations at different temperatures. The adsorption data was found to fit well the second-order rate equation with film diffusion governing the overall rate. The activation energy value was calculated to be 16.74 kJ mol⁻¹. Fluoride can be eluted from fluoride-loaded CCNB using alkali. CCNB can be reused at least for five successive operations.

In this study, BiVO₄ powder is prepared and used as a visible-light catalyst for the photocatalytic degradation of alachlor. The as-prepared BiVO₄ photocatalyst is characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV–vis diffuse reflectance spectra (DRS), and BET surface area analysis. Alachlor could be successfully degraded in the presence of both H₂O₂ and BiVO₄ catalyst under visible-light irradiation. With optimal operating parameters, its degradation efficiency could reach 97 % in 6 h. Factors such as solution pH, catalyst dosage, and the presence of anions are found to influence the degradation rate. To scrutinize the mechanistic details of the alachlor photodegradation, the intermediates of the process are separated, identified, and characterized by solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS). Results suggest that possible transformation pathways may include oxidation of the arylethyl group, cleavage of the N-methoxymethyl group, and N-chloroacetyl moiety.

P(Acrylamide) (p(AAm)) cryogel with superporous structure was synthesized by employing a cryopolymerization technique under freezing conditions. The prepared cryogels were modified by amidoximation to generate new functional groups as amid-p(AAm) cryogel, that binds metal ions, and the metal nanoparticles of those ions were prepared via in situ reduction method. The prepared amid-p(AAm)-M cryogel composites (M: Cu, Ni, and Co) were used as superporous reactor for the catalytic reduction of toxic phenol compounds 2- and 4-nitrophenol (2- and 4-NP) and some dyes methylene blue (MB) and Eosin Y (EY). P(AAm) cryogels and their metal composites were characterized by using FT-IR analysis, SEM images, and AAS measurements. The impact of porosity, the types and amount of metal catalyst, temperature of reaction medium, and so on were investigated for toxic 2-NP reduction by amid-p(AAm)-M cryogel composites. Very high total turnover frequencies (TOF) and low activation energy (Ea) values of 2.46 (mole 2-NP) (mole Cu. min)⁻¹and 20.2 kJmol⁻¹were obtained for catalytic reduction of 2-NP compound catalyzed by amid-p(AAm)-Cu cryogel composites. Consequently, superporous p(AAm) cryogel is the perfect support material for metal nanoparticle preparation and use in catalytic reduction reactions.

The spider webs of Malthonica ferruginea (Panzer, 1804) from the Agelenidae family were used for the evaluation of heavy metal contamination, and major and trace elements presence in the air of Wrocław, Poland. The concentrations of 16 elements were determined (Mg, Al, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, W, Pt, and Pb). Samples of webs were collected from six different locations with low, moderate, and high pollution level (urban of low and high traffic, residential, and postindustrial sites) after 60 days of exposure. Samples collected from high traffic sites and postindustrial site were found to have high contents of elements than residential sites and one of low traffic urban site. The principle component analysis (PCA) and correlation analysis provide important information about the potential sources of the elements in spider webs. Two contamination sources were identified: road traffic emissions and industrial. This was a first-time ever attempt to use webs for biomonitoring of small-scale distribution of airborne major and trace elements in the city of Wrocław.

In indirect olfactometry analysis, to avoid condensation or adsorption processes during or storage of the sample, containers made of suitable materials should be used. Also, reaction between the chemicals during transport from the source of the odour to the research laboratory is an important process which can influence on examinations’ results. Study included determination of the odour and compound concentrations of six gas mixtures. Gas samples were collected by silicone hoses into Tedlar® bags and tested by Nasal Ranger, SM-100 olfactometers and Photovac Voyager gas chromatograph. Time of keeping gas in bags was 78 h, and concentration of compounds was measured every hour, eight times per day. For benzene, acetone, 1,1-dichloroethylene, c-1,2-dichloroethylene, t-1,2-dichloroethylene, methyl ethyl ketone and vinyl chloride, 100 % decrease of concentration has been noticed within 78 h of holding in the bag. Average rate of loss of most compounds concentration was from 0.01 to 2.50 % for the first 30 h and from 0.35 to 18.50 % during the last 48 h of examination. Decreasing of odour concentration measured by Nasal Ranger (NR) in all series was between 0.00 and 4.98 % till 30 h, between 1.91 and 100 % in the last 48 h of test and between 1.61 and 100 % in 78 h. In case of odour concentration measured by SM, those values were, respectively, 1.26–4.93 %, 1.39–4.93 % and 2.40–3.18 %. Values of average rate of intensity decreasing were, respectively, 0.77–1.75 %, 2.36–4.67 % and 1.18–2.07 %. Statistically significant correlation coefficients for compound concentrations and intensity, odour concentration obtained by SM-100 as well as NR were, respectively, 0.55–0.97, 0.47–0.99 and 0.37–0.98.

The soil remediation field is still in development in Brazil. Currently, it is not known how many contaminated sites exist across the country; however, due to the country’s large size and its extensive urbanization and industrialization, it can be postulated that the number of contaminated sites must be very high. To remediate these sites, new sustainable technologies should be identified and evaluated. A technology that was born in the 1990s in the USA, and has been fairly investigated, is the use of nanoparticles (NPs) to degrade contaminants in soils and groundwater. This study aims to present a bibliographic review of nanotechnology application to remediation of soils and groundwater, as well as assess the potential of conducting research in this field in Brazil. This paper first presents an overview of the number of contaminated areas identified in the USA and Europe. The basic concepts of nanomaterials followed by classification, synthesis, and characterization of nanomaterials are explained. The main types of contaminants for which the technique was already applied as well as the chemical reactions between them and NPs are presented. The issues related to delivery and migration of NPs in the porous media is discussed. Concerns regarding the toxicity of nanomaterials are discussed. The in situ applications of nanomaterials for contaminated site remediation are presented. It is concluded that the issues involving remediation of soils and groundwater are site specific and it is not possible to directly transfer knowledge gained from sedimentary soils of temperate climates for residual soils found in tropical and subtropical climate regions. The research on nanotechnology for site remediation in Brazil has just begun, and more efforts are required from the technical and academic professionals to develop nanotechnology as practical technology for the remediation of contaminated sites.

Relative displacement of bromide (Br⁻) and coliphage P22 was analyzed in surface water and vadose zone solution from a 3-ha surface flow constructed wetland. In the vadose zone, water samples at 0.3-, 0.76-, 1.5-, and 3-m depth were collected to quantify Br⁻ and P22 simultaneously added into the wetland influent for a transport study. When P22 was detected, Br⁻ arrived earlier to the monitoring depths than the phage suggesting that preferential flow facilitated P22 displacement in the vadose zone. Concentrations for both tracers indicated that bacteriophage removal through the vadose zone profile was exceeding 99.21 % of the peak concentration observed in surface water samples. For transport parameter estimation, the temporal moment method (MOM) was used to calculate convective velocity (v) and longitudinal dispersion coefficient (D) from the outlet Br⁻ breakthrough curve. The transport parameters were estimated to be 55.7 m day⁻¹ and 1652 m² day⁻¹ for v and D, respectively. For P22 simulation, a first-order removal coefficient of 0.3 day⁻¹ (R ² = 0.943) was assessed. The observed results suggest that this method can be applied for solute transport simulation in constructed wetlands.