Environmental Technology & Innovation最新文献

This review article intends to report the advances in the production and application of biochar from macroalgae and microalgae and its utilization in anaerobic digestion (AD), aiming to achieve zero waste and promote a circular economy. Biochar, a carbon-rich material derived through pyrolysis or gasification, offers environmental and agricultural benefits due to its stability and porosity. By incorporating biochar into AD systems, improved process efficiency, enhanced microbial activity, and nutrient retention can be achieved. An integrated approach on its production and application can minimize biomass disposal impacts, generate renewable energy, and improve the soil and nutrient management. The use of macroalgae and microalgae for biochar production aligns with the sustainability principles, as these resources have high growth rates and there is no direct competition with the arable land. Thus, the focus of this article is to highlight the advances in algal biochar production with emphasis to the factors influencing biochar properties, structure, characterization, mechanism of biochar action, and the impact of biochar addition on AD. It also evaluates the economic and environmental benefits, featuring the role of this approach in achieving a zero-waste paradigm and supporting circular economy development.

Fomesafen is mainly used in soybean and peanut fields to control annual and perennial broad-leaved weeds with strong selectivity and good weed control effects. However, fomesafen has strong persistence and a slow degradation rate in soil. This greatly affects grain yield and the adjustment of agricultural planting structure. In this study, the fomesafen degradation gene cyp57A1 from Fusarium verticillioides, which can be stably expressed in E. coli BL21(DE3), was cloned and transformed into the engineered bacterium P. The degradation rate of fomesafen was explored via high-performance liquid chromatography technology. High-performance liquid chromatography tandem mass spectrometry (HPLC-MS) was used to separate and identify the degradation products of fomesafen in different conditions, and microbial degradation pathways of fomesafen were proposed. Response surface methodology was used to optimize the conditions of the engineered bacteria, and the optimal degradation conditions for the strains were a temperature of 37 °C, a pH of 6.0, and 5 % inoculation. The engineered bacteria successfully degraded 5–500 mg/L fomesafen, and the degradation rate was 82.65 % when the concentration of fomesafen was 100 mg/L. The degradation products were isolated and identified by HPLC-MS, and a total of 8 degradation products were obtained. It was inferred that benzene ring dechlorination, S-N bond cleavage, phenoxy group cleavage, C-N bond cleavage, nitro reduction, amino acetylation, defluorination and other pathways were involved. The excavation of engineered bacteria is highly valuable for resolving the residual fomesafen in the environment.

Innovative fertilizer technology is an effective solution to enhance food security while achieving environmental sustainability. However, current fertilizer technologies aiming to consider the interaction of fertilizer-crop-environment are still insufficient. Here, we designed an innovation fertilizer technology of simple, safe, and biodegradable coating with differentiated release, and then proven the effectiveness to address abovementioned challenges. Our study provides a reference for promoting the innovation, transformation and upgrade of fertilizer industry.

The remediation of arsenic (As) and antimony (Sb) contaminated water is now a global research priority. The concept of "treating waste with waste" by modifying and recycling acid mine drainage sludge (AMDs) for treating As and Sb-contaminated wastewater is widely supported by scholars worldwide. In this study, a novel composite material (MnOx@AMDs) was synthesized via co-precipitating Mn oxides with AMDs. Characterization and adsorption results indicated that, after optimal Mn oxide loading (Mn²⁺: MnO₄^- = 0.075: 0.05 (mol)), MnOx@AMDs-1 exhibited a significant increase in specific surface area and surface positive potential, as well as the formation of abundant mesoporous structures and functional hydroxyl groups. The adsorption of As(V) and Sb(V) onto MnOx@AMDs-1 was best described by the Pseudo-second-order (R² = 0.96 and 0.95) kinetics and Langmuir (R² = 0.99 and 0.96) models, indicating a monolayer homogeneous chemisorption process. The maximal theoretical adsorption capacities at 25°C were 49.31 mg g⁻¹ for As(V) and 155.12 mg g⁻¹ for Sb(V). Post-adsorption characterization revealed that the predominant adsorption mechanisms include complexation, electrostatic attraction, and hydrogen bonding. Furthermore, MnOx@AMDs-1 sustained a removal efficiency exceeding 75 % for As(V) and Sb(V) over five consecutive adsorption-desorption cycles, while the maximum concentration of dissolved Mn (1.87 mg L⁻¹) remained under the 2 mg L⁻¹ threshold set by GB 18918–2002 standards. In conclusion, MnOx@AMDs-1, as a novel adsorbent with high efficiency and environmental friendliness, demonstrates significant potential for application in treating As(V) and Sb(V) contaminated wastewater.

Wastewater from agricultural activities poses significant environmental risks and requires proper treatment before discharge. Phytoremediation using microalgae offers a compelling solution by removing contaminants and generating valuable biomass. This study aimed to optimize glucose and indole-3-acetic acid (IAA) concentrations to maximize pollutant treatment and microalgal biomass production using Chlorella sp. AARL G049 in hydroponic wastewater from lettuce cultivation without added nitrogen and phosphorus. The results showed that Chlorella sp. effectively converted pollutants in undiluted wastewater into biomass, achieving a maximum yield of 1.32 g/L (0.12 g/L/day) with 10.89 g/L of glucose and 10.15 mg/L of IAA. Pollutant removal efficiencies for chemical oxygen demand, ammonium-nitrogen, nitrate-nitrogen, and phosphate-phosphorus exceeded 92 %. An integrated zero-waste biorefinery process produced three value-added products from the microalgal biomass: functional pigments, biodiesel, and biofertilizer. The extracted pigment demonstrated significant antioxidant activity, with DPPH activity of 0.05 mg GAE/g-extract, ABTS activity of 0.31 mg TE/g-extract, and FRAP activity of 0.28 mg GAE/g-extract, as well as high-efficiency UV protection. The lipids extracted contained biodiesel-quality fatty acids with a cetane number of 54 and a high heating value of 40 KJ/kg. Additionally, the residual biomass, post-extraction, contained essential nutrients with an N-P-K ratio of 4.87–0.03–0.68 and 76 % organic matter, making it suitable for plant growth and soil fertilization. Therefore, integrating wastewater treatment with a microalgal biomass-based zero-waste biorefinery demonstrates significant potential for enhancing profitability and sustainability, promoting the sustainable development of the Food-Energy-Agriculture-Environment Nexus.

Tire and road wear particles (TRWPs) have received much attention due to their substantial emission and potentially adverse environmental impacts. The specific contribution of observed contaminants, as critical additives of tires, from TRWPs has not yet been comprehensively studied in the environment. As one of TRWPs generated hotspots, driving school grounds in China were chosen to identify source contributions of heavy metals (HMs) and N-(1,3-dimethylbutyl)-N′ -phenyl-p-phenylenediamine (6PPD) from TRWPs. Significant correlations (P < 0.05) were found between TRWPs and 6PPD and zinc (Zn). The average measured content of 6PPD in road dust was 0.47 ± 0.18 μg/g (n = 50). The estimated level of 6PPD in road dust (5.68 ± 3.36 μg/g, n = 50) was far higher than the measured level of 6PPD in road dust on driving school grounds, implying that TRWPs contributed to 6PPD in road dust from driving school grounds. Compared to the levels of 6PPD in other road dusts, 6PPD in road dust from driving school grounds was higher, exhibiting more significant exposure risks to children with the higher estimated daily intakes. Furthermore, source apportionment through the lead isotopic analysis and positive matrix factorization model revealed that TRWPs were confirmed to contribute more Zn, cadmium (Cd) and lead (Pb) on driving school grounds, notably accounting for 76 %, 31 % and 29 %, respectively. These three HMs presented relatively moderate to strong pollution and corresponding potential ecological risks. Our findings can help identify specific contributions of tire-related additives released from TRWPs in the environment and their potential risks.

Cadmium (Cd) toxicity is a serious environmental threat to living organisms. Nanoparticles (NPs) and plant growth regulators are able to mitigate Cd toxicity and restore crop growth in heavy metals-contaminated soils. However, the synergistic potential of combining 24-epibrassinosteroid (24-epiBRs) and titanium oxide nanoparticles (TiO₂-NPs) to alleviate Cd toxicity and restore soybean (Glycine max L.) production remains unexplored. Thus, a pot-based experimental trial was conducted to assess the effects of applying TiO₂-NPs (15 mg L⁻¹) and 24-epiBRs (10⁻⁷ M), individually and in combination, on soybean growth in soil cultivated with 30 ppm of Cd. The study revealed that Cd toxicity significantly inhibited soybean root length (11.0 %), root dry biomass (63.5 %), root fresh biomass (84.9 %), shoot length (11.7 %), shoot dry biomass (49.0 %), and shoot fresh biomass (27.3 %), compared to the control. Additionally, the toxicity of Cd enhanced the oxidative stress and lowered the photosynthetic efficiency, gas exchange characteristics, and antioxidant defense system of soybeans. Interestingly, the combined application of TiO₂-NPs and 24-epiBRs ameliorated the Cd toxic effects and improved the agronomic traits, photosynthesis efficiency, and antioxidant activity in soybeans by lowering oxidative stress. Specifically, the dual application of 24-epiBRs and TiO₂-NPs effectively lowered the Cd levels in roots, shoots, and leaves of soybean plants by 62.5, 162.7, and 87.1 %, respectively, relative to the control soybean plants grown under Cd stress. Overall, the combined treatment of TiO₂-NPs and 24-epiBRs synergistically reduced Cd uptake and restored soybean physiology in Cd-contaminated soils. Moving forward, further research should include field trials to assess the effectiveness and economic viability of this novel method.

Rice cultivation in saline-alkali land fully utilizes marginal land resources to increase yield, but it brings environmental problems like ammonia (NH₃) and greenhouse gas (GHG) emissions. However, the correlation between soil nitrogen (N) and carbon (C) concentrations and gas emissions, along with the microbial mechanisms, remains unclear in actual saline-alkali rice fields. A 147-day saline-alkali rice field experiment was conducted with five different N-fertilizer applications: NF1 (urea), NF2 (C-based slow-release fertilizer), NF3 (organic-inorganic compound fertilizer), NF4 (microbial fertilizer), and NF5 (inorganic compound fertilizer). The NH₃ volatilization rate had significant positive correlations with carbon dioxide emission flux and soil ammonia-N (p < 0.05). Methane emission flux was significantly (p < 0.05) positively correlated with total organic-C in soil, but was negatively correlated with all N forms. The nirS gene abundance was significantly (p < 0.05) higher than nirK gene by more than 285.65 times, and nitrous oxide emission flux was increased with nirS gene abundance. Two-way analysis of variance indicates that N-fertilizer types can significantly (p < 0.01) affect gas emissions. Weighted average NH₃ volatilization rates were 14.46 % – 27.51 % lower in NF1 and NF3 treatments compared to the other N-fertilizer treatments. The global warming potentials were significantly (p < 0.05) lower in NF1 and NF2 treatments by 17.21 % – 35.93 % compared to CK and the other N-fertilizer treatments. Overall, NH₃ volatilization can be effectively reduced by the NF1 and NF3 applications in saline-alkali rice fields, and NF1 and NF2 are suitable fertilizers to apply for the control of GHG emissions.

A variety of technologies have been used to solve the problems of deep chromaticity, high concentration of organic matter and complex composition of printing and dyeing wastewater, but no major breakthrough has been made in general. Photocatalytic technology shows great advantages in wastewater treatment, and the development of strong oxidizing photocatalytic materials has potential application value. In this study, BiOCl/SrFe₁₂O₁₉ magnetic composite photocatalysts with various ratios of components were prepared using a hydrothermal method. The structure of the photocatalyst was characterized by XRD, PL, EIS and XPS. The photocatalytic performance of the composite sample was evaluated by RhB degradation experiment. The results showed that the optimum sample BiSr-10 had a degradation rate of 99.24 % for RhB, indicating excellent photocatalytic performance. The successful combination of SrFe₁₂O₁₉ and BiOCl facilitated to improve the photodegradation efficiency of RhB by composite photocatalytic materials. And the photocatalytic efficiency for RhB remained close to 82.8 % after five cycles of stability experiments. Analysis of the possible photocatalytic mechanism was based on the aforementioned results. In summary, the prepared BiOCl/SrFe₁₂O₁₉ composite photocatalytic material will bring a new breakthrough for wastewater treatment.

In this study, a hollow micron zero-valent iron (H-mZVI) was synthesized, and its transport and retention property in saturated porous media was determined via a series of column experiments. Furthermore, the maximum migration distance (L_max) and sedimentation rate coefficient (K_dep) models of H-mZVI in saturated porous media were established using statistical methods. The results revealed a distinct hollow structure in H-mZVI, with a density of 1.03±0.03 g/cm³, significantly lower than solid micron zero-valent iron (4.57±0.15 g/cm³). FTIR and XRD analyses indicated no formation of new functional groups on H-mZVI's surface, with iron being the main component. The column experiment demonstrated that the L_max of H-mZVI in saturated porous media was 4.15 times that of solid micron zero-valent iron (mZVI) under the same conditions. The prediction model of L_max aligned with the linear model, where L_max correlated positively with particle size, injection velocity, and H-mZVI concentration, but inversely with ionic strength. Medium particle size and injection velocity were the main engineering parameters to control H-mZVI. The prediction model of K_dep accorded with the quadratic model, and an interaction was observed between medium particle size and injection velocity, which jointly affected the deposition rate of H-mZVI. Moreover, the single particle capture coefficient (η₀) was hereby calculated and analyzed using the T-E theory. Interception primarily governed the precipitation of H-mZVI in saturated porous media, with gravity sedimentation contributing minimally to η₀.