Environmental Abatement Research Articles

Singlet oxygen dominant-activation by hollow structural cobalt-based MOF/peroxymonosulfate system for micropollutant removal

Despite the keen interest in potentially using the metal-organic framework (MOF) in advanced oxidation processes (AOPs), their application for environmental abatement and the corresponding degradation mechanisms have remained largely elusive. This study explores the use of cobalt-based MOF (CoMOF) for peroxymonosulfate (PMS) activation to remove tetracycline (TC) from water resources. Under optimal conditions, the given catalytic system could achieve a TC removal of 83.3%. Radical quenching tests and EPR analysis revealed that SO4•–, HO•, •O2−, and 1O2 could participate in the catalytic degradation, but the discernible removal mechanism was mainly ascribed to the nonradical pathway induced by 1O2. At only 5 mg/L of CoMOF, the performance of the catalytic system was superior to that of PMS alone for different types of micropollutants. The CoMOF/PMS system could also reliably deal with typical anions in water, such as Cl−, SO42−, HCO3−, and PO43−. The MOF catalyst could last for four cycles with a minor decrease in reactivity of ∼30%. However, the removal performance decreased markedly when aromatic natural organic matter (NOM) were present in the water bodies, and the effectiveness was lower in alkaline or acidic environments. Our work offers insights into the catalytic degradation of CoMOF/PMS applied in contaminated water remediation and serves as a baseline for fabricating an efficient MOF with enhanced catalytic performance and stability.

A review on sustainable utilization of red mud based photocatalytic material for environmental pollution abetment

The inventory of the solid waste produced from Aluminium industries (Bauxite Residue) otherwise called red mud stands at an estimated amount of 4 billion tons globally owing to its current generation. So, to reduce the impact on environment, its safe disposal is posing a great threat to eco-friendly atmosphere and its utilization is must for environmental sustainability. High alkalinity nature and airborne dust emissions may posse threat to flora and fauna, but the mineral composition of red mud and red mud derived products found to be a promising material for the utilization in the field of environmental pollution remediation. The high content of largely inert components such as hematite that can be extracted and gives credibility to the idea that red mud can be used as a potential candidate in the field of photo catalysis. This review explores novel methods for treating red mud and extracting minerals, not only provide value to waste but also demonstrated reduced red mud can be used as effective catalyst in environmental abatement. Modification of red mud, extraction of valuable iron oxides creates a novel opportunity for efficient removal of toxic metals, dyes, inorganic and organic pollutants in the cost-effective method and maintains sustainability.

The Impact of Environmental Regulations on Enterprise Pollution Emission from the Perspective of “Overseeing the Government”

This study aims to analyze the impact of “overseeing the government” on corporate pollution control and emission reduction behavior and the choice of corporate emission reduction paths. The central government in China persistently reinforces its environmental oversight of local governments. The effectiveness of environmental protection is closely tied to the performance of local officials and the implementation of the “one vote veto” system in the realm of environmental conservation. In this study, we use the evolutionary game model theory and the DID model to test the impact of “overseeing the government” on the environmental behavior of enterprises. Specifically, this study establishes an evolutionary game model between local government and enterprises, exploring how the local government and the enterprise make decisions. The theoretical findings are validated using pollution data from industrial enterprises in China. The study reveals that enterprises are influenced by local governments primarily when the costs of environmental abatement are relatively low, and the costs of noncompliance are high. Strengthening government oversight leads to a reduction in the intensity and overall emissions of both water and air pollutants. Enterprises respond by increasing their utilization of clean energy sources, reducing their reliance on fossil fuels, and enhancing their pollution control infrastructure to mitigate emissions. Notably, there is no evidence suggesting that enterprises curtail production levels to reduce emissions. Therefore, it is crucial to develop a rational understanding of the relationship between environmental protection and economic performance. In addition, tailored policies should be formulated to enable precise pollution control measures and facilitate the pursuit of high-quality development.

Airline efficiency and environmental impacts – Data envelopment analysis

Airline efficiency has been a research interest for decades. While early airline efficiency research focused primarily on revenue generation and profitability, growing airline social responsibility is driving greater investment into understanding and improving the environmental impact on airline efficiency. This study developed a two-phase, two-stage model using a data envelopment analysis (DEA) approach to simultaneously evaluate airline operations for available seat mile (ASM) generation, revenue passenger mile (RPM) generation, carbon dioxide emissions abatement, and revenue generation on a sample of thirteen airlines. Efficiency evaluation was performed for the years between 2013 and 2015, between U.S. and non-U.S. carriers, and between full-service carriers (FSCs) and low-cost carriers (LCCs). Results indicated more accurate measurement of airlines’ overall efficiency using the proposed DEA model, which included operational and cost factors as input variables and environmental impact as both the input and output variables in the model. Service and environmental factors were found to be significant in determining airline efficiency, with environmental abatement affecting the overall efficiency of airline performance both inside and outside the U.S. when emission reduction effort was properly accounted for. The findings provided theoretical and managerial implications in the assessment of airline efficiency with a special emphasis on incorporating environmental impact in the overall evaluation.

Quantitative evidence from VOCs source apportionment reveals O3 control strategies in northern and southern China

Ground-level ozone (O3) pollution has received widespread attention because its rising trend and adverse ecological impacts. However, the extremely strong photochemical reactions of its precursor volatile organic compounds (VOCs) increase the difficulty of reducing VOCs emissions to alleviate O3. Here, we carried out a one-year comprehensive observation in two representative cities, Tianjin (TJ, Northern China) and Guangzhou (GZ, Southern China). By revealing the concentration characteristics of three different types of VOCs, i.e., initial VOCs without photochemical reaction (In-VOCs), consumed VOCs (C-VOCs), and measured VOCs after the reaction (M-VOCs), we elucidated the important role of C-VOCs in the formation of O3. Although the overall trends were similar in both cities, the average concentration level of VOCs in GZ was 8.2 ppbv higher than that in TJ, and the photochemical loss of VOCs was greater by 2.2 ppbv. In addition, various drivers affecting O3 generation from C-VOCs were specifically explored, and it was found that most alkenes of TJ were key substances for rapid O3 formation compared to aromatics of GZ. Meanwhile, favorable meteorological conditions such as high temperature (T > 31 °C in TJ, and T > 33 °C in GZ), low relative humidity (56% in TJ and 45% in GZ), and stable atmospheric environment (proper pressure and gentle wind speed) also contribute to the generation of O3. More importantly, we combined chemical kinetics and receptor model to quantify the three-type VOCs source contributions and assess the potential impact of C-VOCs sources on O3 production, thus proposing environmental abatement technologies corresponding to the three types of VOCs. The differences in the comparison results of the three-type VOCs highlight the need to reduce O3 pollution from C-VOCs sources, which provides insights for future clean air policies development.

Emerging biotechnological strategies for food waste management: A green leap towards achieving high-value products and environmental abatement

Food wastes have gained increasing attention by the public, national, and international organizations due to substantial social, environmental, and economic apprehensions, climate variation, and the depletion of fossil reserves. Although food wastes represent serious ecological problems; however, they possess significant candidature for biotransformation processes into a spectrum of commodity compounds due to their rich composition of carbohydrates, lipids, and proteins. There are a few things to consider regarding waste disposal infrastructure, which is undoubtedly an ecological concern. Although waste disposal infrastructure improvements in developed countries do not receive much attention as rapid healthcare facilities. Waste disposal is a priority in developed countries for a number of reasons. However, addressing these issues solely by the applications in developing countries will not be sufficient. Due to cultural, economic, and resource gaps between developed and the developing countries, several unique challenges must be solved to improve the waste management system in developing countries. It is essential to evaluate the current tendencies and technological improvement in the modification of food supply chain because the biomass transformation processes define the significance of the substrate as well as the functional expenses. Although the generation of industrially important compounds via waste valorization shows an excellent opportunity, a comprehensive appraisal of the automation supported by improving processing economics is necessary before industrial execution.

The role of public-private partnership investment and eco-innovation in environmental abatement in USA: evidence from quantile ARDL approach.

The current research investigates the role of public-private partnership investment (PPPI) and ecological innovation (ECO) along with economic growth on the environmental abatement (i.e., carbon dioxide emission, particulate matters 2.5) in the USA. Quantile autoregressive lagged (QARDL) method was employed during the study period of 1990–2015. The study findings confirm that under long-run estimation, GDP and PPPI are causing more environmental abatement in the form of CO2 emission and haze pollution like PM2.5. The factors like ecological innovation and GDP2 are playing their role towards lowering the CO2 emission and PM2.5 under different quantiles. Furthermore, it is observed that under short-run estimation, past values of the carbon emissions and PM2.5 have their significant and positive relationship with their current values. Besides, the findings through Wald test estimation confirm that parameter constancy of the speed of adjustment parameter is rejected at 1% significance level for the CO2 emission and haze pollution like PM2.5 in USA. Besides, present study also provides some policy implications.

Accounting for spatial variability in life cycle cost-effectiveness assessments of environmental impact abatement measures

PurposeThe environmental and economic impacts of livestock production systems are typically assessed using global characterisation factors and data, even though several impact categories call for site-specific assessments. Here, we account for spatial variability by addressing potential interactions between geographic locality and the cost-effectiveness of farm investments that aim to reduce system environmental impact, using Danish pig production as a case-in-point.MethodsAn LCA-based, spatially explicit environmental abatement cost framework was developed to assess the cost-effectiveness of potential environmental abatement strategies. The framework was tested for Danish pig production in a “4 manure management × 4 geographic location” scenario analysis design. In addition to the baseline, the alternative manure management strategies were on-farm anaerobic digestion, slurry acidification and screw press slurry separation, implemented in an integrated pig farming system. The geographic locations differed in their proximity to Natura 2000 areas and in pig farming density. Eight different impact categories were assessed through an LCA using spatially explicit characterisation factors whenever possible, and annualised abatement potential was estimated for each manure management scenario and in each geographic location. We also estimated the financial performance for each scenario, through a discounted cash flow analysis at a whole-farm level.Results and discussionWe observed significant interactions between geographic location and system environmental and economic performance under baseline conditions. Significant location effects were also observed for the cost-effectiveness of all manure management strategies tested. Anaerobic digestion was the only “win–win” strategy that increased farm profits while reducing system environmental impact in two of the geographic cases: when implemented in a region of high pig farming density located near Natura 2000 and when implemented in a region of high pig farming density located far from Natura 2000 areas. Slurry acidification and slurry separation achieved sizeable abatement potential for impacts on ecosystem quality but incurred large additional costs in all geographic case studies considered, particularly when arable land was limited near the pig farm.ConclusionsAccounting for basic spatial characteristics within an environmental abatement cost framework had significant impact on the cost-effectiveness of on-farm investments for mitigation of system environmental impact. To the best of our knowledge, no studies to date have utilised such spatial characteristics within environmental abatement cost modelling of livestock farming systems. The presented framework has the potential to be further expanded using more detailed spatial, economic and geophysical data, which could ultimately improve decision-making regarding cost-effective investments that aim to improve the sustainability of livestock farming operations.

Pollution haven effect in North-South trade: a theoretical analysis under the mixed duopoly Cournot model

ABSTRACT Utilizing the framework of the mixed duopoly Cournot model in North-South trade, this paper provides evidence that Pollution Haven Effect exists under optimal environmental regulations and discusses how it is affected by the production costs and environmental abatement costs in the developed and developing countries. We also find that under optimal environmental regulations, the heterogeneous impacts on the Pollution Haven Effect make developed countries motivated to reduce the environmental abatement costs and make developing countries more incentive to reduce the production costs.

The Threat of Offshoring on the Environmental Regulation

This paper aims to analyze how the threat of offshoring can lead policymakers to adopt more lenient emissions tax policies. This study focuses on analyzing the relationship between the stringency of environmental policies and firms’ strategic offshoring decisions when a government is concerned about the negative effects of increased offshoring such as domestic job losses. The analysis is based on an archetypal proximity concentration framework that has been enhanced by considering environmental regulations and abatement technology. The results imply that the threat of offshoring is more likely to impact emissions tax rates when firms experience higher productivity, or when offshoring leads to a significant level of domestic unemployment. That is, in these cases, the threat of offshoring is more likely to make the government lower emissions tax rates more than the optimal tax rate. Although the direct impact of offshoring on environmental policies is studied in many related works, the indirect impact of offshoring-that is, the threat of offshoring- on environmental policies has been seldom studied.

The Environmental Kuznets Curve with Recycling: A Partially Linear Semiparametric Approach

This paper is the first to study a comparatively new Environmental Kuznets Curve which traces empirically the relationship between environmental abatement and real GDP. Our model is a partial linear semi parametric model that allows for two way fixed effects to eliminate the bias arising from two sources. We use data for recycling and real GDP, for fifty states of the United States for the years between 1988 and 2017. We find evidence that this relationship is characterized by an increasing curve which confirms the existence of a J curve, a finding that agrees with the predictions from recent theoretical models.

Cost-effectiveness of environmental impact abatement measures in a European pig production system

Many emerging technologies and alternative farm management practices have the potential to improve the sustainability of pig production systems. The implementation of such practices is not always economically viable. The goal of this study was to assess the cost-effectiveness of such environmental mitigation strategies in pig systems, using an Environmental Abatement Cost analysis. We considered four pig housing (improved insulation, increased ventilation efficiency, frequent slurry removal, increased slurry dilution) and three manure management related abatement strategies (anaerobic digestion, slurry acidification, slurry separation), implemented as stand-alone and as a set of “pig housing–pig housing” and “pig housing–manure management” combinations. We calculated their annual equivalent value through a discounted cash flow analysis and then their annualised abatement potential through a cradle-to-farm gate life cycle assessment. The baseline system against which the analysis was conducted was a typical Danish pig production system, over a 25-year time horizon. The environmental impact categories considered were Non-Renewable Resource Use (NRRU), Non-Renewable Energy Use (NREU), Global Warming Potential (GWP), Acidification Potential (AP) and Eutrophication Potential (EP). Pig housing–anaerobic digestion combinations were the most cost-effective options for GWP, NRRU and NREU. Their abatement costs ranged from −€0.237 to €0.70 per tonne CO2 eq., −€0.146 to €0.36 per g Sb eq. and -€1.75−04 to €3.11−04 per GJ abated respectively. Anaerobic digestion was the most cost-effective stand-alone investment for GWP (−€0.206 per tonne CO2 eq.), NRRU (−€0.0493 per g Sb eq.) and NREU (−€1.00−04 per GJ), and slurry acidification for AP (€303 per tonne SO2− eq.) and EP (€1190 per tonne PO43− eq.) mitigation. Overall, measures for mitigation of GWP, NRRU and NREU required higher investments than for AP and EP, but also generated profit. The framework developed in this study can potentially aid decision making in the choice of environmentally and economically sustainable pig system modifications.

CuO/Zn-CeO2 Nanocomposite as an Efficient Catalyst for Enhanced Diesel Soot Oxidation

Development of non-noble metal catalysts with improved structural, surface, and redox properties for catalytic soot oxidation has gained an enormous interest. Among practical alternatives, ceria-supported transition metal oxides have been proved to be the satisfactory catalysts for soot oxidation due to their outstanding redox properties and oxygen transfer capability promoted by the strong interaction between metal oxide and ceria interfaces. Following the above considerations, in the present work, CuO/Zn-CeO2 nanocomposite was prepared by a wet impregnation method and investigated for catalytic soot oxidation. To probe the significance of nanocomposites, pure counterparts, namely, CuO/CeO2, CuO/ZnO, and Zn-CeO2, were also synthesized. Various characterization techniques, namely, TEM-HRTEM, N2O chemisorption, XRD, ICP-OES, BET, Raman, XPS, and H2-TPR, were employed to investigate the structural, surface, and redox properties. Pure CuO/ZnO and CuO/CeO2 catalysts showed a soot oxidation activity with a T50 of 613 and 526 °C, respectively, under the practical conditions of NO concentration of 500 ppm and 20% O2. Interestingly, the CuO/Zn-CeO2 nanocomposite exhibited a remarkable higher soot oxidation activity with a T50 of 460 °C. The enhancement in the soot oxidation activity has been attributed to a strong interaction between the highly dispersed CuO and Zn-CeO2 support, which resulted in the desired textural properties and abundant surface defects (Ce3+ species as well as oxygen vacancies). In addition, the long-term stability test verifies an excellent reusability of the CuO/Zn-CeO2 nanocomposite towards soot oxidation without appreciable loss in the activity. The present study demonstrates the significance of ceria-based nanocomposite catalysts for environmental pollutant abatement.

Operation-based uncertainties in river waste load allocation and their impacts on controlling discharges

ABSTRACTVariations in quality or quantity of reservoir discharges and of wastewater treatment plants (WWTP) are typical sources of uncertainty in controlling and management of river water quality downstream. This study evaluates and discusses the impacts of these operation-based uncertainties on waste load allocation (WLA) policies, like water quality trading (WQT), by Monte-Carlo simulation. For this purpose, we chose the Sefidrud River in northern Iran and developed an economic-based WLA in this area through a simulation-optimisation approach. The river with 1150 reaches is simulated by coding in MATLAB and linked to a multi-objective particle swarm optimization (MOPSO) algorithm in which the two objectives are minimisation of environmental violations and abatement costs. For uncertainty analysis through Monte-Carlo simulation, river flow and kinetic rates, dissolved oxygen (DO) at headwater, pollution loads of dischargers, and temperature are considered as primary variables. Results show that the success of WLA is mostly reliant on the DO concentration of headwater, occurrence of seasonal floods, and river aeration rate. The implications of the findings are also analysed for WQT. In particular, the above uncertainties are highlighted as possible threats for the success of discharge permit markets because polluters could be penalised or rewarded for uncertainties regardless of their pollution discharges. Consequently, effective WQT under uncertainty is likely to lead to a need for more monitoring to resolve potential disputes from uncertainties.

Technical Note: A PRELIMINARY STUDY TO QUANTIFY THE ENVIRONMENTAL IMPACTS OF CONCRETE AND CORK FLOORING

Cross-laminated timber (CLT) is currently sought as a sustainable and green building material. It does not meet the International Building Code sound insulating requirements, and either a concrete slab or hardwood flooring is needed to meet the acoustic and vibrational performance benchmark. Cork, the bark of the cork oak, is well known for its sound insulating properties and often used for flooring applications in Europe. The cork-based flooring system is a potential solution to the acoustic problem faced by the CLT building industry. The goal of this preliminary study was to quantify the environmental impacts of a concrete and a cork-based flooring system that includes CLT. A life-cycle analysis (LCA) is conducted to focus on a cradle-to-gate comparison of a cork flooring system with a locally sourced concrete flooring system for use in a proposed CLT structure in Portland, OR. The LCA reveals that the global warming potential (GWP) of concrete is 25% higher for the concrete flooring system. For cork flooring, the GWP is mainly driven by inorganic compounds in the flooring assembly. The main source for cork is Portugal, which increases the GWP of the cork flooring system, in contrast to that of concrete flooring, which typically has a regional production and supply system. As environmental abatement costs increase, the profitability of cork flooring can increase to justify the creation of an appropriate system to close the loop.

Gray water and environmental externalities: International patterns of water pollution through a structural decomposition analysis

Despite regulatory measures restricting industrial and agricultural operations from pouring pollutants into lakes, streams, and rivers, around 1.1 trillion m3 of wastewater were still disposed in waterways around the world in 2009 and this amount continues to grow. Several studies have analyzed the determinants of gray water increase at local level, but so far none has explored them in an international context to highlight the role of global value added chains and the dichotomy between developed and developing nations. In order to provide insights on the dynamics of water pollution worldwide, this paper analyzes the main drivers of gray water discharge during the 1995–2009 period and the effort on reducing gray water compared to other environmental externalities. Based on the World Input-Output Database, a structural decomposition analysis (SDA) of gray water generation shows that domestic demand for food is the main driver of gray water changes in all countries, while relocation of industrial activities to developing nations has disproportionally transferred this burden from developed countries' manufacturing industries. We highlight that while national policies should target water pollution from the agri-food sector within each country, water discharges from manufacturing sectors in global value chains need to be regulated from an international perspective. Besides the empirical evidence on water pollution drivers currently lacking in the environmental literature, this paper also introduces a novel hybrid multiplicative-additive SDA that overcomes the issue of distributing large interaction terms in standard additive models and allows simulating mitigation scenarios. It portrays the heterogeneity among sectors of how environmental abatement policies affect water and air pollution.

In site acid template induced facile synthesis of porous graphitic carbon nitride with enhanced visible-light photocatalytic activity

Porous g-C3N4 was prepared through thermal polycondensation of supramolecular aggregates, which were formed from melamine and HNO3, H2SO4, HCl or HI by induced hydrogen bond. Various acids acted as templates to cause the formation of porous structures on the g-C3N4 during the condensation process of melamine. And the prepared pg-C3N4 exhibited notably photocatalytic performance for degrading Rhodamine B and phenol compared with bulk g-C3N4 due to its high surface area and changed band potentials. Obviously, this work supplied a facile method to synthesize porous g-C3N4 material, which was widely used in environmental abatement and energy related fields.

Charge separation in branched TiO2 nanorod array homojunction aroused by quantum effect for enhanced photocatalytic decomposition of gaseous benzene

As known, the electron transfer behavior in photocatalysis is short-distance transportation, which leads the photo-induced electrons and holes to be localized. The temporarily separated electrons and holes will recombine with each other in the localized region. In this paper, we successfully achieved electron transfer in a homojunction of branched rutile TiO2 nanorod @nanoparticle core-shell architecture by quantum confinement effect aroused by the nanoparticle, which is proved by the blue-shifting in UV–vis absorption spectrum of the homojunction. Meanwhile, an absolute charge separation is also achieved by the long-distance electron transfer along the single-crystalline rutile TiO2 nanorod as uninterrupted high-speed electron transfer channel to FTO substrates. Based on the effective charge separation, the photocatalytic decomposition of gaseous benzene by the homojunction is significantly enhanced, yielding 10 times CO2 than that of the nanorod array. This homojunction interfacial charge separation, aroused by quantum effect, through long-distance transfer along the single-crystalline nanorod gives us inspiration to achieve efficient charge separation with defect-less interfaces, which might can be utilized for real-time environmental abatement and energy generation simultaneously.

The EU ETS and corporate environmental abatement

ABSTRACTThis article studies the relationship between firm-level emissions-to-cap ratio (ETC) and environmental abatement, by using a unique and extensive data set of 10 762 installations covered by the European Union Emission Trading Scheme (EU ETS) matched to 5931 firms. We find that a shortage of emissions allowances is related to more abatement in later years while a surplus of emissions allowances results in worse subsequent environmental performance. This finding underscores the importance of reducing the global amount of allowances in the ETS system. Our results also suggest that stakeholder pressure and the creation of transparency concerning corporate environmental performance are likely to support the effectiveness of the system.

Modeling a sustainable Saudi Arabian economy: the real issues

This paper develops a macroeconomic framework for creating a competitive and sustainable Saudi Arabian economy, taking into account the interrelationships among social, environmental, and economic factors. The objective of the research is to build a model that will allow for evaluating the effects of a wide range of emissions abatement policies on economic growth and development. The research methodology is grounded in econometric modeling of the Saudi economy over the period 1980–2010. The estimated parameters of the model were used to project long-term gross domestic product (GDP) growth paths based on three environmental degradation abatement scenarios. The results suggest that the sustainability of economic growth in Saudi Arabia critically depends on aggressive emissions-reduction policies since policy scenarios corresponding to higher pollution cuts yielded higher, sustained long-term GDP. The results also broadly reject the Environmental Kuznets Curve (EKC) hypothesis, implying that a turning point in the relationship between CO2 emissions and per capita GDP is yet to be attained.