In this study, regeneration of spent granular activated carbon (GAC) with reactive dye by hydroxyl and sulfate radical-based advanced oxidation processes (microwave (MW) +persulfate (PS)), (Fe(II)+ PS), and (O₃ + H₂O₂) were evaluated. The adsorption of the dye to the GAC surface was characterized by chemisorption and Langmuir isotherm. Regeneration processes have been optimized by the response surface methodology to determine the operating conditions that will provide the highest adsorptive capacity. The optimum conditions of (MW + PS), (Fe (II) + PS), and (O₃ + H₂O₂) processes were process PS anion of 45.52 g/L, pH of 11.4, MW power of 126 W, and duration of 14.56 min; Fe (II) of 3.58 g/L, PS anion of 73.5 g/L, duration of 59.8 min, and pH of 10.9; and H₂O₂ of 2.8 mole/L, flow rate of 8.14 mg ozone/L, duration of 32.8 min, and pH of 5.3, respectively. For (MW + PS), (Fe (II) + PS), and (O₃ + H₂O₂) processes, the adsorptive capacity under optimum conditions was found as 4.36, 8.89, and 8.12 mg dye/g GAC, respectively. For (Fe (II) + PS) and (O₃ + H₂O₂) processes, these values are approximately equal to the adsorptive capacity of raw GAC (8.01 mg dye/g GAC). The predicted values of the adsorption capacities by the obtained models were in good agreement with the actual experimental results. Preference Ranking Organization Method for Enrichment Evaluation approach was used in the preference of the appropriate regeneration process. The adsorptive capacity of regenerated GAC, operating cost of the regeneration process, change in the adsorptive capacity during the regeneration cycle, and carbon mass loss criteria were taken into account. The order of preference of regeneration processes was determined as (Fe (II) + PS)> (MW + PS)> (O₃ + H₂O₂) considering all criteria.

The problems of data leakage and unreliable information transfer in the management process make sustainability management an inevitable need for future development. Globally, there is increasing attention paid to blockchain technology and particularly its application in addressing sustainable management issues, both from academia and industry. Aiming to deepen the understanding of how blockchain technology could deal with sustainable management issues across different disciplines, this paper investigates the latest research on the application of blockchain technology in sustainable management published from 2017 to 2021. It is found that there is a drastic surge of publications in the recent 2 years. The analysis focuses on authors’ origins, the collaboration network of the keywords, countries, and research topics covered. The application of blockchain technology in five key sectors of sustainable management, encompassing energy management, construction management, supply chain management, environmental management, and e-government management, is selected for further analysis detail. Also, a general framework for applying blockchain technology is proposed for broadening its use and dealing with sustainable management issues. The findings show that the identified 108 publications are distributed in 75 different journals, and scholars from China, the UK, and the USA have been working closely in BT-based sustainable management research. Blockchain technology is just emerging in sustainable management, and there is a great potential for applying blockchain technology to improve sustainable management performance and, more importantly, to provide solutions to quite a few long-lasting problems in these sectors. Opportunities for future research are also presented and discussed.

Environmental pollution affects the quality of the natural environment where major and trace elements have been commonly found to accumulate in biotic and abiotic matrices. The purposes of this research were (1) to assess the accumulation and distribution of 24 major and trace elements in water, sediments, and muscle and gills of ten native fishes from two natural areas with different degree of protection in the Atlantic Rainforest, (2) to discuss potential origin of the elements related to the land use, and (3) to assess the human health risk for water and muscle fish consumption in general and fisher populations. Major and trace elements were determined by inductively coupled plasma mass spectrometry. Concentrations of Ag, Cu, and Se in water and Cr, Cu, Hg, Mn, Ni, and Zn in sediment were higher than the international guidelines for the aquatic biota protection. Muscle Cr, Cu, Ni, Pb, Hg, and Zn from several species (both studied areas) were above guidelines for human consumption. The bioaccumulation factor (< 6936) was higher in gills than in muscle, and indicated that Andromakhe saguazu, Andromakhe paris, Gymnogeophagus lipokarenos, and Steindachnerina biornata were macroconcentrators of Zn, and Australoheros ykeregua, G. lipokarenos, and Hemiancistrus fuliginosus were macroconcentrators of Se and Sr. The hazard index and target hazard quotient indicated that there is no risk from chronic consumption of water or fish. The results show the need to reduce the entry of pollutants into streams, paying special attention to reducing runoff in deforested areas.

Protection of water resources implies the responsible consumption, and the return of this resource with the best physicochemical conditions. In organizations, water is consumed both directly in their facilities and indirectly in the products or services acquired for their operation, requiring a water accounting based on the life cycle perspective. This study aims to assess the comprehensive water footprint of the main campus of the Technological University of Pereira (Colombia), based on the ISO 14046:2014 standard, and analyze the influence of wastewater treatment. Impacts on water scarcity were evaluated using the AWARE method, while the impacts on human health and ecosystems were evaluated using the ReCiPe method. Specific modeling of the wastewater treatment plants on campus was conducted. A total of 102,670 m³.y⁻¹ of water scarcity was accounted for. Water consumption per person was 17.8 m³ of which 86.2% corresponded to indirect activities. Similarly, indirect activities were responsible for more than 98% of the impacts on human health and ecosystems, where more than 95% were due to infrastructure construction and 2% due to electricity consumption. Although the wastewater treatment on campus reduced the impact on ecosystems by 14%, if a tertiary treatment was added, these impacts would have a 40% of additional reduction. Efforts in recycling programs were also quantified in 712 m³ of avoided water scarcity for secondary users. The findings suggest focusing actions on sustainable construction and purchases to improve water management in organizations.

Famine exposure or air pollution is linked to type 2 diabetes mellitus (T2DM). However, their combined effects on T2DM remain largely unknown. A total of 11,640 individuals were obtained from the Henan Rural Cohort Study. According to their birthdate, participants were divided into three famine exposure subgroups: fetal exposed, childhood exposed, and unexposed groups. The air pollutants (particles with aerodynamics diameters ≤ 1.0 µm (PM₁), ≤ 2.5 µm, and ≤ 10 µm, and nitrogen dioxide) concentrations of each individual were estimated by a spatiotemporal model. Participants were divided into low or high air pollution exposure groups taking the 1st quartile value of air pollutants as the cut-off point. Logistic regression model was used to analyze independent and joint associations between air pollution exposure, famine exposure, and T2DM. Positive associations of air pollution and famine exposure with T2DM were found. Participants who experienced fetal or childhood famine and also were exposed to high concentrations of any kind of the air pollutants had a much higher risk for T2DM than those with no famine and low air pollutants exposure (taking PM₁.₀ for example, the odds ratio [OR]: 1.76, 95% confidence interval [CI]: 1.25, 2.47 for fetal famine, and OR: 1.64, 95%CI: 1.13, 2.40 for childhood famine). After stratified analysis, similar results were observed in women. The results indicated that both famine exposure in early life and air pollution exposure in adulthood are related to increased risk for prevalent T2DM, and they have combined effects on T2DM.

The principal problem in dense cities is air pollution and the damage to the environment caused by air pollution. Roadside landscape plants are exposed to air pollutants, especially in small urban centers caused by congested traffic, heating, and industrial enterprises. According to the type of landscape plants, being a good biomonitor varies according to their absorbing capacity of air pollutants. Chromium (Cr), cadmium (Cd), and zinc (Zn) are the leading pollutants originating from emissions. They are selected and negatively affect several landscape plants in high concentrations. This study aimed to determine their concentration changes according to organ and washing status by commonly used 14 landscape species in parks. The heavy metal holding capacity of 14 species used was compared; chromium, cadmium, and zinc concentrations changed significantly depending on the factors evaluated to adsorb them. The ranking of the accumulation levels was determined as Zn > Cr > Cd and was detected at higher levels in unwashed organs than in the others. Chamaecyparis lawsoniana (A. Murr.) Parl. was shown better biomonitoring features on heavy metal accumulation among all species. Its unwashed leaves’ deposited Cd, Cr, and Zn were 154 ppb, 6400 ppb, and 39,940 ppb, respectively.

Carbonized wood is a biofuel from cellulose pyrolysis with frequent smoke and life-threatening carcinogenic emissions. Carbon monoxide (CO), particulate matter (PM₂.₅), metalloids and trace elements from charcoals from six commonly used tropical timbers for carbonization in Donkorkrom (Ghana) were assessed. During combustion, Anogeissus leiocarpa charcoal emitted the least CO (4.28 ± 1.08 ppm) and PM₂.₅ (3.83 ± 1.57 μg/m³), while particulate matter was greatest for Erythrophleum ivorense (28.05 ± 3.08 ppm) and Azadirachta indica (27.67 ± 4.17 μg/m³) charcoals. Erythrophleum ivorense charcoal produced much lead (16.90 ± 0.33 ppm), arsenic (1.97 ± 0.10 ppm) and mercury (0.58 ± 0.003 ppm) but the least chromium (0.11 ± 0.01 ppm) and zinc (2.85 ± 0.05 ppm). Nickel was greatest for A. indica charcoal (0.71 ± 0.01 ppm) and least for Vitellaria paradoxa (0.07 ± 0.004 ppm). Trace elements ranged from 342.01 ± 2.54 ppm (A. indica) to 978.47 ± 1.80 ppm (V. paradoxa) for potassium and 1.74 ± 0.02% (V. paradoxa) to 2.24 ± 0.10% (A. indica) for sulphur. Besides A. leiocarpa charcoal, which ranked safest during combustion, the high PM₂.₅ and CO emissions make the other biofuels hazardous indoors. Kitchens need air filters to absorb these emissions together with the use of improved cook stoves. These carcinogenic metalloids would necessitate that their ashes be properly discarded without human contact. Yet, the charcoals would be much suitable as soil amendment bio-char for plant growth quality improvement.

The functionalized graphene oxide-ZnO (fGO/ZnO) nanoflower composites have been studied as a photocatalyst material for flow photodegradation of humic acid (HA) in real samples. The fGO/ZnO nanoflower was prepared via hydrothermal methods. The chemical and physical properties of the synthesized photocatalyst have been carried out by several techniques, including X-ray diffraction (XRD), scanning electron microscope-energy-dispersive spectrometer (SEM-EDS), Fourier transform infrared (FTIR), and UV-Vis spectrophotometer. The photocatalytic study of degradation of HA by flow system is reported. The optimum condition for degradation was found at pH 4.0, a flow rate of 1 mL min⁻¹, and a light intensity of 400 mW cm⁻². The degradation efficiency of HA also was influenced by several anion or cation concentration ratios on the system. This method was applied for the degradation of HA in extracted natural HA from the soil, and the efficiency achieved at 98.5%. Therefore, this research provides a low-cost, fast, and reusability method for HA degradation in the environment.

There is an increasing demand for the development of inexpensive and effective approaches for the oil–water separation due to the global concern in oil industries. The present study was conducted to fabricate graphitic carbon nitride/thermoplastic polyurethane (g-C₃N₄/TPU)-coated stainless steel meshes via the dip-coating method to investigate the capability of g-C₃N₄ nanosheets (CN-NS) in oil–water separation. CN-NS was synthesized using the polycondensation process followed by exfoliation with Hummer’s method. We studied the effect of TPU and CN-NS concentration on wettability behavior to obtain an optimized coating solution. CN-NS-coated mesh showed superoleophilic/hydrophobic behavior at CN-NS:TPU ratio of 50:50, and it efficiently passed oil from the emulsified water-in-oil mixture (with 50 wt.% oil) with the efficiency of 99%. The wettability behavior of superhydrophilic/underwater superoleophobic was also obtained at CN-NS:TPU ratio of 80:20, and it was able to separate water from the emulsified water-in-oil mixture with the efficiency of 79% under gravity. Both filters were able to separate free water and oil mixtures with flux and efficiency of 6114 L.m⁻².h⁻¹ and ~ 99.99%, respectively. The mechanism of wettability behavior of the coating is mainly related to the functional groups on the edge of g-C₃N₄-NS, thus increasing the hydrophilic properties of the surface. In addition, the micro-nano hierarchical structure of the surface coating improves its roughness due to the presence of CN-NS, which is effectively embedded into the hydrophilic TPU. More importantly, commercially available TPU chemical and simple fabrication of g-C₃N₄ from an inexpensive precursor make the method reported herein as a significant alternative for large-scale application.

A hypothesis was proposed that the activated sludge was converted into hydrochar full of phenolic hydroxyl and then was made into coagulant by graft copolymerization. The results show that under the addition of HCl, the content of phenolic hydroxyl on the surface of hydrochar (SBC) under hydrothermal conditions increased sharply, up to 1.586 mmol/g, showing that HCl dosage of 0.10 g/g dᵣy ₛₗᵤdgₑ and holding time of 4 h was recommended. Under graft copolymerization with the addition of DMC, the coagulant was synthesized. Based on the analysis by FTIR, XPS, zeta potential, etc., the possible synthesis route of coagulant from SBC was that phenolic hydroxyl on SBC was activated by the initiator and then the polymerization between SBC and DMC was triggered. The optimal grafting conditions are gotten. It was named as SBCHCₗ₀.₁₀ g, ₄ ₕ-g-DMC₀.₇. The removal by SBCHCₗ₀.₁₀ g, ₄ ₕ-g-DMC₀.₇ on COD and turbidity in domestic wastewater is up to 69% and 93%, respectively. The component of COD indicated that almost all particulate COD and most of colloidal COD are removed. On the contrary, the removal on dissolved COD can be neglected. Most of NH₃-N and P is kept in the wastewater. This is in favor of subsequent reuse and biological treatment.