Next Sustainability最新文献

Water pollution, aggravated by the release of industrial dyes into the water bodies, is a significant environmental issue. This study presents the synthesis and characterization of a MXene-based composite, MXene/CoFe₂O₄/g-C₃N₄, tailored for enhanced photocatalytic dye degradation. The resulting composite is systematically analyzed through various physico-chemical and optical characterization techniques to explore the morphological features and photocatalytic efficacy. The results unveils a multilayered structure for MXene/CoFe₂O₄/g-C₃N₄, characterized by a suitable bandgap, enhanced light harvesting efficiency, as well as proficient charge carrier separation, and low recombination rate. It forms a Z-scheme/Schottky heterojunction exhibiting higher efficiency for degradation of rhodamine B (93.1 % in 180 min) under visible light. Active species like O₂^•− and ^•OH play a vital role in the photodegradation process, and the prepared catalyst exhibits a stable performance up to 5 cycles. This work reveals new possibilities for designing and fabricating heterojunction photocatalysts, showcasing excellent capabilities for efficient and sustainable environmental remediation.

The issue of water contamination resulting from textile dyes has garnered public attention. To address this issue, a new highly stable, greener, nontoxic composite material (ZBH.Sn) consisting of Sn²⁺ doped Zn-Bi mixed metal hydroxide (ZBH) was effectively fabricated. The adsorbent underwent a thorough investigation of its structural and morphological properties utilizing XRD, HR-TEM, FE-SEM, FTIR, XPS, Zeta, and DLS. XRD confirms the crystallinity of mixed phases of both zinc and bismuth hydroxides. The hexagonal sheet-like morphology is evident in SEM, and elemental mappings show that individual elements are evenly distributed on the external surface. The ZBH.Sn adsorbent demonstrates an adsorption efficiency in the removal of Fuschin blue (F.B.) from wastewater systems. With optimized 2.5 mg ZBH.Sn in 20 mL (0.05 mM) of F.B concentration at pH 6, the maximum adsorption capacity was 80.56 % in 180 minutes at 298 K. The detailed thermodynamic information (ΔG= −2.477 KJ/mol) including adsorption maximum capacity q_max (1472.75 mg/g), adsorption equilibrium constant (k₂= 3.7×10⁵ g.mg¹.min¹), and adsorption efficiency (80.56 %) were obtained to evaluate the different reaction performances for F.B by ZBH.Sn. Such observation suggests that these materials could serve as effective adsorbents for removing F.B. from wastewater because of their high adsorption capabilities and low cost.

Bioenergy with Carbon Capture and Storage (BECCS) is a key negative emission technology considered by many integrated assessment models (IAMs) to achieve the 2℃ or 1.5℃ goals in the Paris Agreement. However, the technical feasibility and economic costs of BECCS in these IAMs have been widely debated, which increases the uncertainty in the projection of climate change in the 21st century. Therefore, this paper reviews the latest understanding of BECCS. The key findings reveal the limitations of current models in projecting the capacity and costs of bioenergy with carbon capture and storage (BECCS), mainly due to insufficient consideration of ecological consequences, including availabilities of biomass and difficulties in the transportation of biomass and CO₂. To reduce uncertainties in the capacity and costs of BECCS, it is urgently needed to apply spatially explicit method for estimating the life-cycle emissions and the complete cost items when deploying BECCS, optimize the network of biomass acquisition, power plants retrofitting and transportation of biomass and CO₂, and represent the changes in the availability of biomass (for different types of bioenergy plants) under the impacts of climate change. This paper emphasizes the gap between the potential capacity of BECCS and the demand for BECCS that is needed to achieve the climate goals. Suggestion on policy interventions is provided to accelerate the application of BECCS from the aspects of economic tools, regulatory tools, and information tools. Deployment of BECCS could be accelerated to halt the rapid rise of global annual average temperature and reduce the risk of carbon lock-in from fossil-fuel supply infrastructure. As BECCS could play a key role in achieving ambitious climate targets, it is important to maintain a balance between environmental, social, and economic considerations in the Earth system under a high sustainability of development.

For the purpose of improving mechanical qualities, starch-based film hydrogel can be crosslinked. The choice of crosslinking agent is critical in adjusting hydrogel performance to fit the needs of specific applications. The present investigation examined the impact of two non-toxic crosslinking agents, namely citric acid and oxidized sucrose, on the mechanical and swelling properties of hydrogels. When compared to oxidized sucrose crosslinked hydrogels (OSH), citric acid crosslinked hydrogels (CAH) often offer a larger swelling; however, OSH without plasticizer is not included in this comparison. The OSH has the highest swelling value of 292% at pH 7, whereas the CAH has the highest swelling value of 116% at pH 7. Contrary to OSH film, which can only achieve 2.0 MPa, CAH film has a tensile strength of up to 3.75 MPa. Meanwhile, OSH film can achieve the greatest elongation of 54%.

This article explores the climate mitigation strategies of the 15 industries with the largest carbon dioxide emissions in Sweden. Starting from two carbon budget alternatives, we analyse the mitigation projections of the companies in relation to what can be considered their fair share of the remaining carbon budget for Sweden. We furthermore determine the uncertainties associated with the strategies. The results suggest that if the communicated mitigation plans are implemented as planned, the companies overdraft our main, 1.5-degree, budget option but stay within the alternative 1.7-degree budget. The analysis shows, however, that the timing and efficiency of emission reductions are crucial. Already small delays or lower efficiency in implementation, result in evident overdrafts of also the alternative budget. There are also substantial political and technical risks which can prevent timely mitigations. The article makes a novel contribution by analyzing industries’ mitigation strategies relative to their share of the remaining carbon budget. The article demonstrates the importance of transparent industrial climate mitigation strategies and in particular the need for policymakers to set incentive structures to promote strategy implementation.

Carbon revenues from the REDD+ projects are important to reduce deforestation and increase carbon sinks in developing countries. Such revenues are not possible without assessing the baseline emissions, the forest reference emission level (FREL), and the effectiveness of the REDD+ activities. This study aimed to assess the carbon emission reductions from reducing deforestation, carbon removals from enhancing forest carbon stocks, and carbon revenues in the Vavuniya district, Sri Lanka by assessing baseline emissions and FREL (2001 – 2020) in dry monsoon forest using the Google Earth Engine and the phenology-based threshold classification. The Vavuniya district is one of the war-affected dry zone districts showing a significant loss in forest cover. This study considered the carbon pools aboveground, belowground biomass, and litter to calculate forest carbon stocks since a significant change can be observed in these pools due to forest loss. The estimation shows that the annual depletion of carbon stocks was 45,083.6 MgC between 2001 and 2020, which accounts for the total carbon emissions of 165,306.6 MgCO₂. FREL established for the period of the Paris Agreement was at 155,187.9 MgCO₂ yr⁻¹. Around 94,331.0 MgCO₂ of annual carbon emissions could be reduced if REDD+ actions are implemented between 2020 and 2030. While annual carbon removals from the open forest could be 7731.5 MgCO₂. Based on the carbon price selected at the voluntary carbon market and the European Union emission trading system, total emission reductions and removals can be equivalent to carbon revenues ranging from approximately USD 7.3 million to USD 87.5 million. These revenues are important for the Sri Lankan government to promote conservation efforts for the remaining forests to better conserve biodiversity. The estimation suggests high carbon revenues, which can attract successful implementation of the projects through appropriate policy interventions and sectoral collaboration, which can then contribute to long-term economic development and climate change mitigation.

Transformer oil is the insulating oil that is utilized in power transformers for insulation and cooling during the operation of transformers. After a long run, the properties of the transformer oil such as breakdown voltage, and dielectric dissipation factor decrease to 32 kV, 0.41% while water content increases by 31 ppm resulting in waste oil. The disposal of waste transformer oil (WTO) is a big issue since it is contaminated with many virulent pollutants such as PCBs, PAHs, harmful gases, etc. which have adverse effects on the environment and living beings. Many scientists in this area studied to reduce its environmental impact and disposal problem by using different methods of recycling and re-use of WTO or re-refined into new transformer oil and also utilized in blended form with diesel fuel as an alternative fuel in diesel engines resulting in less smoke and hydrocarbon emission, increased BTE and NOx emission. In this review, we provide information about waste transformer oil, its toxic effects on the environment, the various techniques to recycle WTO, and its application in alternate fuels.

Lithium mining from brines raise environmental issues due to huge volumes of both saline and freshwater being constantly pumped in desertic environments. Data indicating the slow depletion of both underground water levels and lagoon surfaces in the regions where large lithium brine mining exploitations are located have recently being disclosed. Amongst different direct lithium extraction methodologies, DLE, for more sustainable lithium recovery, a few proposals aim at the recovery of freshwater from the high salinity brines. About 900 kg of freshwater could potentially be recovered per cubic meter of processed native brine. The water evaporation and freshwater production capabilities of a simple and an active solar still are compared in this work. These are two simple and relatively low-cost technologies that could be adapted to existing solar evaporation ponds. The two systems were thermodynamically modelled. Equations were derived which were fed with real meteorological data from the Olaroz salt lake location and brine properties derived from the Pitzer model for the said brine. Analysis of the heat fluxes show that the behavior of both systems is relatively similar with large heat losses that are responsible for neither of the systems reaching the evaporation rate of the evaporation ponds.

Waste plastics pose significant environmental risks due to their non-biodegradable nature and accumulation in the environment. The pandemic has exacerbated this issue by increasing the production of plastic medical waste such as surgical masks. This study developed Ni/Al-MOF-derived catalysts for pyrolysis, an effective plastic waste utilization technology. By optimizing conditions, the study successfully converted waste surgical masks, made primarily of polypropylene, into gasoline or diesel range chemicals. The oil yield from polypropylene waste reached 72.8 % using Ni/Al-MOF-derived catalysts with 5 % Ni loading at 450°C, while surgical masks yielded 58.9 % oil under the same conditions. Catalyst characterization revealed a high surface area and evenly distributed Ni particles in MOF-derived Al₂O₃, maximizing catalytic performance. This catalyst provides a promising solution for converting waste surgical masks into liquid fuels, reducing the environmental impact of plastic products, and promoting plastic waste recycling.

Herein we have made a comprehensive analysis for the conversion of CO₂ to fuel (CH₄) on two dimensional MXenes (M=Mo, Hf) of the type M₂C. Evaluation of parameters like Mulliken charge, adsorption energy, bond angle and bond distance demonstrated that activation is more pronounced with Hf₂C compared to Mo₂C due to transfer of higher electron density to CO₂ in the former than in the latter case. CO₂ adsorbed M₂C realizes large shift of valance and conduction band vis-a-vis free M₂C, leading to substantial charge transfer from MXenes. The enhanced activation of CO₂ over Hf₂C has been confirmed from the increased splitting of π and π* energy level of CO₂ for Hf₂C compared to Mo₂C. The dense electron localization contour maps further explained the ease of electron transfer to CO₂ involving Hf₂C. Analysis of Gibbs free energy for successive steps for the conversion of CO₂ to CH₄ revealed that fuel conversion is more feasible with Hf₂C over Mo₂C.