Water, Air, & Soil Pollution最新文献

Water sources is contaminated with different types of impurities. Several technologies and materials are used for purification of contaminated water. Most of the reported technologies costly and produce secondary contaminants. Nowa day, researchers are used hydrogels for water purification. Hydrogels are applied drug delivery, catalysis, tissue engineering, sensing and removal of environmental pollutants, applications, and energy storage. Hydrogels have specific functional groups as –COOH, -SO₃H, -OH, CONH₂, -NH₂, -SH and other groups which are responsible for applications. Hydrogels were removes impurities from water through physio-adsorption, chemo-adsorption, sorption and secondary forces. The aim of this review is to explore the preparation method, conceptualization of hydrogels and their uses in water purification. It describes details of toxicants in water, different types of hydrogels and their synthesis methods. These hydrogels were used for water purification and evaluated for removal capacity with respect to toxicants in water. Nowadays hydrogels are modified based on their applications to create specific functionality on hydrogel. Specific hydrogel will be emerging tool for specific applications.

This study investigates the adverse effects of cadmium (Cd) on rice plant growth and the mitigating potential of graphitic carbon nitride (g-CN), supported by detailed material characterization. Cd exposure significantly inhibited plant growth, reducing root length by 54% and shoot length by 33%. However, the introduction of g-CN improved overall plant health, reducing Cd toxicity by 35% at an optimal dosage of 150 mg/L. The g-CN's effectiveness is attributed to its structural and chemical properties, as revealed by comprehensive characterization. Field Emission Scanning Electron Microscopy (FESEM) analysis showed thin, flake-like structures, while X-ray diffraction (XRD) studies confirmed its highly crystalline nature, with peaks corresponding to the (100) and (002) planes of crystalline g-CN. Fourier transform infrared (FTIR) analysis identified functional groups such as the tri-s-triazine unit and C-N/C = N stretching vibrations, confirming the formation of g-CN. Brunauer–Emmett–Teller (BET) analysis demonstrated the mesoporous nature of the material, with a specific surface area of 66 m²/g, indicating its high reactivity and potential for interaction with plant systems. These properties likely contribute to g-CN's ability to enhance root architecture, increase nutrient absorption, and promote fresh biomass production. Additionally, g-CN helped maintain a balanced carbon-to-nitrogen ratio by supporting improved photosynthesis and nitrogen uptake. These findings underscore the potential of g-CN as a nanomaterial for mitigating heavy metal stress in crops, offering a promising approach to enhancing crop resilience in contaminated environments.

Nowadays, the use of antibiotics is widespread which is causing great pressure on the ecological environment. Incorporation of nitrogen source in biochar can improve its adsorption performance, which is widely used as an adsorbent due to its high efficiency and low-cost. In this study, municipal sludge and red mud were used as raw materials, urea as nitrogen source and KOH and ammonium oxalate as activators to prepare N-doped sludge-based magnetic biochar (NBC) by co-pyrolysis for adsorption of norfloxacin (NOR) in wastewater. The experiment was conducted using 50 mL of NOR wastewater with a concentration of 100 mg/L. The optimal adsorption conditions were identified as 1.6 g/L dosage, pH 5, and temperature 25 °C. The actual adsorption capacity of NBC reached a maximum of 160.25 mg/g. The maximum adsorption capacity of NBC was 388.82 mg/g, which was measured by Langmuir isothermal modelling. The adsorption kinetics are consistent with a pseudo-second order model, while the adsorption isotherms are consistent with the Langmuir and Freundlich models. The characterization demonstrates that NBC is a rough and porous material, with a specific surface area of 192.8397 m2/g and a surface functional group composition including -OH/NH, C = C, C = N, C-O. The main mechanisms of this research include pore filling, π-π interactions, H-bonding and electrostatic interactions. The introduction of a nitrogen source to sludge-based magnetic biochar (BC) has improved its performance in various aspects of adsorption. This paper demonstrates the excellence of NBC by comparing the adsorption performance of NOR with that of BC, which has great potential for future practical applications.

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Soil aggregation plays a critical role in the maintenance of soil nutrient storage and supply. After five years of crop biomass management, field samples from a sandy loam mountain hilly soil were examined for aggregate distribution, physical subfractions within aggregates, and organic nitrogen (N) fractions, such as nonhydrolyzable N (NHN), hydrolysable ammonium N (HAN), amino-sugar N (ASN), amino-acid N (AAN), and hydrolysable unidentified N (HUN). The total N pool and theoretically mineralizable N were used to calculate the soil N storage and supply capacity, respectively. The total N, mineralizable N, and coefficient of mineralisation rate were all considerably raised by crop biomass incorporation. Analysis of covariance structures showed that the organic N fractions had an impact on the supply and storage of N in the soil, with HUN and AAN contributing the most to the potentially mineralizable N and; also HUN and AAN making up the largest portion of the total soil N pool. In comparison to bulk soils that had not had biomass removed, the amounts of organic N components HAN, ASN, AAN, HUN, and NHN were higher by 98.2%, 87.2%, 71.47%, 38.91%, and 43.27%, respectively. Compared to microaggregates, biomass incorporation enhanced soil macroaggregates by 9.37% and had higher organic N percentages and accumulation efficiency. The mineralizable N was significantly correlated with all fractions of N. The inorganic nitrogen and total nitrogen (TN) were higher in 100% biomass inclusion-T₅ (60.01 and 841.58) and lowest in total removal of biomass-T₁ (24.92 and 479.74). The > 2 mm aggregate size significantly contributed more in organic N fractions rather than 2–0.25 mm or less.

Freshwater resources are limited on the earth, and we have highly contaminated it with various pollutants. Reuse and recycle of wastewater is the need of the hour in the present Anthropocene. Removal of heavy metals from the wastewater is one of the prerequisites for further reuse of the water. Evidence shows that heavy metal contamination can disrupt ecosystem functioning and human health. Several researchers have reported the bio-sorption process using waste material as alternative adsorbents to remove heavy metal from aqueous medium. Despite the advantages of the bio-sorption process, there are still several research need to be included like evaluation of bisorbent against industrial wastewater and its economic assessmment for its commercialization. This review synthesizes the contemporary information on heavy metal (Cd, Pb, Ni, Cr, As, Hg) removal from various biomaterials (plant-based, algae-based, animal/bacteria/fungi/protozoa) from the literature published between 2007 and 2020.

Fruit and vegetables waste are a promising feedstock for production of ethanol have garnering significant attention due to its potential and environmentally sound energy source including reducing waste sent to landfills, providing a source of renewable energy, and reducing reliance on fossil fuels. In this study, fruit wastes from orange, pomegranate, and papaya, as well as vegetable wastes from potatoes, tomatoes, and carrots, were selected as feedstocks for ethanol production. Orange, pomegranate, and papaya wastes exhibited the highest concentrations of fermentable sugars, followed by tomato and carrot wastes. The fermentation of these feedstock using appropriate microorganisms resulted in the production of ethanol with yields ranging from 25 to 50%. The analysis of ethanol performance results showed that orange, pomegranate, papaya, and potato samples were within allowable range whereas tomato and carrot samples were above the allowable range. Moreover, the purified ethanol used in the experiment was clear and colourless. This paper conclude that fruit and vegetable waste represent a promising feedstock for ethanol production showing the highest potential for ethanol production. However, further research is required to optimize fermentation processes and address challenges of using these feedstock and processing for scalable ethanol production.

The western coastal area of Alexandria City, Egypt, faces significant environmental challenges due to heavy metal (HM) contamination in beach sediments, driven by intensive urbanization, tourism, commercial harbors, and industrial activities. Therefore, this study focuses on geochemically assessing HM levels in sediment samples from 28 sites and employed various descriptive and multivariate statistical approaches, pollution indices, and sediment quality guidelines (SQGs) to identify pollution hotspots, define contamination grades, and assess the quality of beach sediments. The average concentrations of Cd, Co, Cr, Cu, Pb, and Zn were 25.7, 30, 2.2, 7.5, 2.9, and 8.0 times, respectively, compared to the geochemical background (carbonate sedimentary rocks). et al.-Hanuvil Beach, relatively elevated contents of these metals were recorded. In addition, samples showed Zn levels higher than the corresponding probable effect concentration (PEC) and effect range medium (ERM) values, suggesting adverse impacts on biota. The principal component (PC) analysis revealed the anthropogenic origin of Cd, Co, and Pb in PC1, the mixed origin of Cr, Cu, Mn, and Zn in PC2, and the natural source of Fe in PC3. According to the applied single pollution indices, HM contamination grades were ranked in ascending order of Mn < Fe < Cr < Cd < Cu < Pb < Zn < Co. In conclusion, the HMs (Cu, Zn, Cd, Co, Pb, and Cr) in the study area are anthropogenic, attributed mainly to untreated discharge of municipal and industrial wastewater and solid wastes, atmospheric deposition of air pollutants, and tourism activities.

MnO₂/CoMoO₄/ NF (Nickel foam) was obtained by loading MnO₂ onto the surface of CoMoO₄/NF using electrodeposition. The results of degradation experiments showed that the degradation efficiency of levofloxacin (LVF) (15 ppm, pH = 6.12) over MnO₂/CoMoO₄//NF reached 80.4% in 30 min when the PMS concentration was 0.08 mM. When the pH was lower or higher than the pH value of the original solution, the performance of the material significantly decreased due to the repulsive effect between the catalyst and SO₅²⁻. Cobalt and manganese ions exhibited a synergistic effect on the activation of PMS. The HCO₃⁻ ions showed the most significant inhibitory effect on the degradation of LVF. The free radical trapping experiments indicated that ·OH, and O₂^·− were the main active species in the degradation process of levofloxacin. The cyclic stability experiments proved the MnO₂/CoMoO₄/NF catalysts were efficient, stable and easy to recover.

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Compost-based organic amendments are an alternative to improve the soil's physical and chemical properties, particularly in soils with poor fertility. These amendments can be derived from natural sources like sewage sludge and food waste, enhancing the soils' structure, water retention, and essential nutrients. This study assessed the effects of adding two composts to sandy soil: sewage sludge (SS) and sewage sludge mixed with food waste (SS + FW). Two controls were used, unamended sandy soil (Ctrl-Soil) and sandy soil mixed with a commercial mineral fertilizer (Ctrl-CF). The soil and the organic amendments were characterized, and all treatments were monitored during a three-week incubation period. Afterward, Rosette Bok Choy plants (Brassica rapa var. rosularis) were cultivated for three weeks. Organic matter (OM) and water content (WC) were proportionally higher as compost rates increased for SS and SS + FW. Significant differences were observed in the 20% and 30% rates compared to the control groups. All rates of SS + FW remarkably increased cation exchange capacity (CEC) compared to the controls, while for SS it was somewhat higher. On the contrary, SS electrical conductivity (EC) was significantly higher in SS 20% and 30% rates. The results showed that SS compost decreased the soil pH and SS + FW increased it with an alkaline tendency. Both composting amendments in their 10% rates improved seed germination over the unamended soil; however, seeds did not germinate in the 20 and 30% treatments, which could imply that these rates are not suitable for the cultivation of Rosette Bok Choy. The best-growing outcomes on roots and shoots were observed in the unamended soil followed by 10% SS + FW. The study findings indicate that organic amendments such as SS + FW are more appropriate for the tested soil and crop compared to the control with mineral fertilizer, which yielded the lowest growth results. The improved growth with organic amendments can be attributed to their ability to increase soil organic matter, whereas mineral fertilizers often contribute to soil degradation over time.

With economic development and technical innovation, many factories near city and adjacent suburbs are abandoned. The abandoned chemical materials, contaminated soil, and groundwater could threaten people’s health. The noncarcinogenic and carcinogenic risks of thirteen elements in soil and groundwater around an abandoned pesticide factory in southwest China were investigated. The results show as following, (1) the hazard indexes of heavy metals in soil were 0.409 for adults and 1.315 for children, the exposed children were suffering the adverse health effects. The carcinogenic risk of soil for both adults and children were acceptable. (2) in groundwater, both noncarcinogenic and carcinogenic risk for children and adults were unacceptable. The carcinogenic risk of Ni and As in groundwater were 3.42 × 10^–3 and 1.21 × 10^–4, which were greater than the marginal value posing health effects (1 × 10^–4). (3) For both soil and groundwater, the element of Mn was the major contributor to noncarcinogenic risk, with 84.1% for children and 61.3% for adults. Via oral ingestion, health risk index was 1.38 for adults and 1.11 for children. Health risk index value through respiratory and dermal contact for children were respectively 1.26 and 0.82, and that for adults were respectively 0.49 and 0.28. Oral ingestion and respiratory were the major pathways to threaten people’s health.

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