Suitable Treatment Technology Research Articles

Comprehensive evaluation method based on objective and subjective factors: A case of printed circuit board resin waste treatment technologies in China

Given the significant diversity in printed circuit board (PCB) resin waste compositions, selecting the most suitable treatment technology is urgent. This study proposes a comprehensive evaluation index system integrating resource and energy use, environmental impact, and cost-benefit analysis. The method enhances the accuracy of subjective weight determination and matrix calculation while reducing the impact of subjective bias. Three treatment technologies are examined: incineration, composite manufacturing, and pyrolysis. Pyrolysis consumes fewer resources and less energy, with minimal environmental impact, scoring above 0.2156 for resource and energy use and above 0.2588 for environmental impact. Composite manufacturing yields superior economic benefits, the score is above 0.3219. Incineration's comprehensive evaluation results are notably lower across various copper content levels. Manufacturing composites is optimal below 16 % copper content, while pyrolysis is preferred above. The case study fully demonstrates the method's reliability and advantages, contributing to recommended technological choices for waste management.

Study on the Effect of Thermal Assisted Combined Plant-Based Biomass Conditioning on Dehydrated Sludge Bio-Drying

In recent years, the production of municipal sludge has gradually increased, and finding suitable sludge treatment and disposal technologies is an urgent problem that needs to be solved. Bio-drying of sludge is a relatively efficient and convenient drying method, but currently, there are still problems with unstable drying effects and high moisture content of dried products, which limits the subsequent utilization of bio-drying products. This article uses a thermal assisted bio-drying device that simulates carbonization waste heat reflux, and uses corncob, straw, sawdust, and rice husk as conditioners to carry out bio-drying of dehydrated sludge. The influence of the types and ratios of conditioner under thermal assistance on the bio-drying of dehydrated sludge is explored. The results showed that the moisture removal efficiency of the corncob and straw groups was better, and their material moisture content could be reduced to below 10% within 24 h. The lower calorific value of straw-sludge drying products was the highest, at 11,608.8 kJ/kg. The best conditioner under the conditions of this experiment was straw, and the drying effect was best when the mass ratio of dehydrated sludge to straw was 4:1. The research results contribute to promoting the development of sludge bio-drying technology.

Integrated treatment of stormwater using multistage filtration (MSF) for domestic application (reuse)

Stormwater harvesting is a promising solution for global freshwater depletion, particularly in tropical regions with abundant rainfall. However, it is not widely used due to the lack of suitable treatment technologies for domestic applications. Multi-stage filtration (MSF) is an effective integrated treatment technology that provides a cost-effective alternative for stormwater treatment. This study investigated MSF's capacity for treating stormwater at different stages. The MSF designed and built comprised the down-flow roughing filter (DRF) and slow sand filter (SSF). The results achieved by the MSF for the treated effluents were: pH (7.1–8.1), temperature (27.6–29.4°C), electrical conductivity (EC) (100–190 µS/cm) and total dissolved solids (TDS) (70–130 mg/L). Turbidity removal efficiency of the MSF was in the range of 36–99% (5.825–164.05 NTU) and the overall average removal efficiency of the MSF was 74%, 90% and 86% for total coliforms (TC) (360–11 800 CFU/100 mL), faecal coliforms (FC) (0–1 300 CFU/100 mL) and Enterococcus spp. (120– 1 400 CFU/100 mL), respectively. The study identified stormwater reuse potentials based on international guidelines and benchmarks. For the treated effluent, pH, temperature, EC and TDS were all within the permissible limits for toilet, laundry, bathing, recreational and agricultural water reuse, while turbidity suited agricultural (non-food crop) and restricted urban reuse. 46% of the effluent was suitable for recreational purposes as this satisfied the 50 NTU standard. 62.5% of the effluent satisfied the FC standard for toilets and urinals and agricultural reuse (non-food crop) purposes, while 87.5 % of the effluent satisfied urban reuse purposes (restricted access). 66.67% of the effluent satisfied the Enterococcus spp. standard for agricultural reuse (non-food crop). All treated effluents satisfied the TC bathing standard. This study shows that after minimal disinfection, stormwater effluents offer potential reuse in household applications, thereby reducing potable water demand.

Wastewater treatment in semi-arid industries: A focus on technologies and potential for reuse

The aim of this article is to identify, based on a literature review, the most suitable water treatment technologies for the production of reuse water to be used by industries that are often present in the Brazilian semi-arid region. For this research, we selected studies on water treatment with low implementation costs and advanced development for implementation. This study identified water treatment technologies for the production of reuse water in the leather and footwear, textile, metallic and non-metallic mineral extraction and food and beverage industries. The search was carried out in the scientific databases Scopus and Web of Science, with no restrictions on the year of publication. Based on the selected articles, a summary was made of the most suitable water treatment systems for each industrial sector, providing an overview of the treatments recommended for water-scarce regions. Water reuse can be implemented in various industrial activities, including the use of boilers, cooling towers, toilet flushing, local irrigation and reintroduction into the process as a by-product. There are various methods of water treatment, although it is necessary to assess which is most suitable for each type of industry. Aspects such as the amount of effluent generated, the necessary properties of the water to be reused and the cost of the project must be carefully evaluated if the benefits are to be achieved.

Entropy for q-rung linear diophantine fuzzy hypersoft set with its application in MADM

A notable advancement in fuzzy set theory is the q-rung linear diophantine fuzzy set. The soft set theory was expanded into the hypersoft set theory. By combining both the q-rung linear diophantine fuzzy set and hypersoft set, this study describes the notion of q-rung linear diophantine fuzzy hypersoft set that can handle multi sub-attributed q-rung linear diophantine fuzzy situations in the real world. Furthermore, some of its algebraic operations such as union, intersection and complement are described in this study. In addtion, the entropy measure of the q-rung linear diophantine fuzzy hypersoft set is established as it is helpful in determining the degree of fuzziness of q-rung linear diophantine fuzzy hypersoft sets. A multi-attribute decision making algorithm based on suggested entropy is presented in this study along with a numerical example of selecting a suitable wastewater treatment technology to demonstrate the effectiveness of the proposed algorithm in real-life situations. A comparative study was undertaken that describes the validity, robustness and superiority of the proposed algorithm and notions by discussing the advantages and drawbacks of existing theories and algorithms. Overall, this study describes a novel fuzzy extension that prevails over the existing ones and contributes to the real world with a valid real-life multi-attribute decision making algorithm that can cover many real-world problems that are unable to be addressed by the existing methodology.

Novel technology for industrial VOCs exhaust treatment under dual-carbon target based on multivariate statistical analysis

Abstract Against the background of the dual-carbon target, the treatment of volatile organic compounds (VOCs) emissions in the industrial sector, especially in the chemical industry, has become an urgent environmental issue. To provide scientific and objective guidance for technology selection, this study constructs a comprehensive evaluation model based on the combination of entropy weighting method and hierarchical analysis method for the complete progress of VOCs treatment technologies, taking into account the four main factors of environment, economy, management and technology and the thirteen secondary factors under them. The model provides in-depth quantitative analysis and evaluation of ten common VOCs end-of-pipe treatment technologies. The evaluation results show that thermal combustion, catalytic combustion, adsorption-concentration-combustion, and photocatalysis exhibit high comprehensive efficacy in VOCs emission treatment, with relative weight values of 0.1273, 0.1252, 0.1214, and 0.1184, respectively. These findings provide essential references and guidance for chemical companies in selecting suitable VOCs treatment technologies, which help to realize the win-win situation of environmental protection and economic development. This study fills the gap in evaluating VOCs emission management technologies and provides a practical decision-making tool for relevant decision makers.

Wastewater Treatment Technologies Selection Using Analytical Hierarchy Process and VIKOR Methods: A Case Study

Due to the ever-increasing water scarcity problem across the globe, the treatment of wastewater is an important public health and socio-economic issue. Treating wastewater through proper technology is vital to protect the ecosystem from unsafe and contaminated matter available in wastewater. Identification of suitable wastewater treatment technologies is a complex Multi-Criteria Decision Making (MCDM) problem since it includes many conflicting assessment criteria. The objective of the paper is to construct an integrated model using the Analytical Hierarchy Process (AHP) and VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) for evaluating wastewater treatment technologies (WWTTs). AHP is applied to calculate criteria weights, and the VIKOR method is applied to prioritize and select the best WWTTs. The proposed model is applied to selecting the best WWTT among four alternatives and seven criteria. It is found that the proposed model yields better results when compared with other MCDM solutions.

Bioelectrochemical system for enhancing anaerobic digestion of pharmaceutical-containing domestic wastewater

The unprecedented recent expansion in usage of paracetamol (AAP) has increased the need for suitable wastewater treatment technology. Furthermore, direct interspecies electron transfer promotion (DIET) offers simple and efficient approach for enhancing anaerobic digestion (AD). In this work, using AAP-containing domestic wastewater as feed, control AD reactor (RC) was operated, besides three DIET-promoted AD reactors (REV, RMC and REVMC, referring to electrical voltage “EV”-applied, nFe3O4-multiwall carbon nanotube (MCNT)-supplemented, and “EV applied + MCNT supplemented” reactor, respectively). Maximal treatable organic loading rates by RC, REV, RMC and REVMC were 3.9, 3.9, 7.8 and 15.6 g COD/L/d, corresponding to AAP loading rate of 26, 78, 156 and 312 μg/L/d, respectively. Methane production rate generated by RC, REV, RMC and REVMC reached 0.80 ± 0.01, 0.86 ± 0.04, 1.40 ± 0.07, and 3.01 ± 0.17 L/L/d, respectively. AAP expectedly followed hydroquinone degradation pathway, causing AD failure by acetate accumulation. However, this performance deterioration could be mitigated by DIET-promoted microbes with higher methanogenic activity and advanced electric conductivity. Economic evaluation revealed the favourability of MCNT addition over EV application, since payback periods for RC, REV, RMC and REVMC were 6.2, 7.7, 4.2 and 5.0 yr, respectively.

Treatment of antimicrobial azole compounds via photolysis, electrochemical and photoelectrochemical oxidation: Degradation kinetics and transformation products

The degradation kinetics and transformation products of pharmaceutical azole drugs from Watch List 2020/1161 (fluconazole, FCZ; miconazole, MCZ; clotrimazole, CTZ; and sulfamethoxazole, SMX) are examined individually and as a mixture in Milli-Q water and simulated wastewater (SWW) upon treatment with three different advanced oxidation processes: (i) photolysis (UV), (ii) electrochemical (eAOP), and (iii) photoelectrochemical (eAOP/UV). For individual pollutant degradation, UV was found to be significantly more effective for SMX and CTZ compared to MCZ and FCZ. Whereas when treating the azole drugs mixture, eAOP/UV was determined to be the most effective treatment method. The degradation efficiency was higher in Milli-Q than in SWW because the treatment efficiency depended on the matrix compositions. The degradation products formed under different processes were identified, and the routes of transformation were proposed. The results of this study can assist in the selection of the most suitable treatment technology depending upon the pollutant or matrix.

Performance and mechanism of La-Fe metal-organic framework as a highly efficient adsorbent for fluoride removal from mine water

Water fluoride pollution has caused non-negligible harm to the environment and humans, and thus it is crucial to find a suitable treatment technology. In this study, La-Fe@PTA adsorbent was synthesized for the defluoridation of mine water. The results showed that the optimum conditions for defluoridation by La-Fe@PTA were pH close to 7.0, the initial F− concentration of 10 mg/L, the dosage of 0.5 g/L and the adsorption time of 240 min. Compared with SO42‒, Cl‒, NO3‒, Ca2+ and Mg2+, CO32‒ and HCO3‒ presented severer inhibition on fluoride uptake by La-Fe@PTA. The adsorption process fits well with the pseudo-second-order kinetic model and Freundlich model, and the maximum adsorption capacity of Langmuir model was 95 mg/g. Fixed-bed adsorption results indicated that fluoride in practical fluorinated mine water could be effectively removed from 3.6 mg/L to less than 1.5 mg/L within 130 bed volume (BV) by using 1.5 g La-Fe@PTA. Furthermore, the adsorbent still had good adsorption capacity after regeneration, which confirms the great application potential of La-Fe@PTA as a fluoride ion adsorbent. The mechanism analysis showed that La-Fe@PTA adsorption of fluorine ions is a physicochemical reaction driven by electrostatic attraction and ion exchange.

Optimum chain desalination process design for treatment of high TDS brine: A case assessment for future treatment of extracted brine from Shenhua CO2storage site

AbstractCarbon dioxide‐enhanced water recovery (CO2‐EWR) is a promising strategy for managing reservoir pressure build‐up and mitigating the risk of fault activation resulting from CO2injection in deep saline aquifers. CO2‐EWR can also be employed for supplying the required water for different applications after a treatment stage for the produced saline water. In this study, a brief review on CO2‐EWR technology and its necessities are first carried out. After that, the feasibilities, advantages, and challenges of various available treatment technologies that can potentially be used to treat high total dissolved solids (TDS) brine are comprehensively assessed. Based on comprehensive evaluation on technologies, a chain desalination process, consisting of pretreatment, main treatment, and post treatment, is proposed as a strategic path for the treatment of high TDS brine extracted from the Shenhua CCS site. It is concluded that coagulation‐flocculation and gravity filtration are needed as primary stages to remove suspended particles, while membrane distillation (MD) is selected as a suitable main treatment technology for high TDS Shenhua brine. Then, MD treatment is comprehensively discussed for a small‐scale treatment of extracted Shenhua brine assuming that the pretreated brine is free of suspended solids. After presenting the heat and mass transfer equations for direct contact membrane distillation (DCMD), a mathematical thermodynamic model is programmed in EES (Engineering Equation Solver) software to briefly analyze the performance parameters of DCMD. The results indicate that the designed DCMD, in the absence of auxiliary systems and considering the inherent temperature of extracted brine from different formations, has the capability of producing 15.1 kg m−2hr of freshwater from the extracted brine of the Shihezi formation layer. In the case of employing the auxiliary system of flat‐plate collector (FPC) combined with heat exchanger (HX) to heat up the extracted Shenhua brine to the desired temperature of 80°C, the amounts of produced flux are enhanced by 133%, 72%, and 45% for the brine extracted from Liujiagou, Shiqianfeng, and Shihezi formations, respectively. Using the yearly solar radiation model in TRNSYS software, the maximum solar radiation on the tilted surface at the location of Shenhua project in Inner Mongolia Autonomous Region of China reaches 3800 kJ m−2hr at 1 PM on April 1. Considering maximum solar radiation on the tilted surface, it is proved that a small‐surface FPC can supply the required energy to heat up the extracted brine from its inherent temperature to the desired temperature of 80°C. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.

Seasonal Characterization and Possible Solutions for Municipal Solid Waste Management in the City of Patna, Bihar, India

The present study aims to characterize the municipal solid waste (MSW) generated in the municipality of Patna, the second-largest city in Eastern India. MSW is heterogeneous and the composition varies with seasons and within the different parts of the city. MSW samples were characterized for the three different seasons Winter (November), Summer (May), and Monsoon (August) to select feasible waste treatment methods. The physical characterization indicates that the major fractions of the MSW were biodegradable (48.83%) and inert (18.26%), which shows variations in different seasons of about ~5%. On a seasonal basis, the chemical characterization of MSW revealed that the moisture content varies between 43.21% to 51.78%, and volatile matter between 20.18% to 29.45%. ash content between 20.20% to 26.23% and fixed carbon between 4.11% to 5.91%. The C/N was found to be between 15.81 to 28.84 and the calorific value lies between 1212 to 2627 kcal.kg-1 during different seasons. The characterization of MSW highlights the virtue of waste segregation at the source and developing an efficient MSW system, including the potential for recycling, composting, anaerobic digestion, and production of refuse-derived fuels (RDFs). The outcomes of the present study will be helpful for Patna Municipal Corporation (PMC) in the planning for implementing suitable waste treatment technologies for integrated solid waste management systems (ISWM).

Advancements in laundry wastewater treatment for reuse: a review

Laundry related activities produce huge quantity of wastewater that is very rich in lint, dyes, surfactants, and detergents. The large amount of laundry wastewater (LWW) is generated by extensive human activities. LWW needs to be treated in order to tackle the challenging problem of water pollution and to accomplish water sustainability. To achieve this success, LWW can be reused for several purposes such as irrigation, construction activities, vehicle washing etc. However, there are several challenges in the reclamation of LWW like effective handling of the wastewater and meeting the regulatory criteria. Based on the literature review it seems that a single treatment process is not sufficient to treat LWW up to acceptable reuse standards. To that end, different treatment chains have been proposed: i) hybrid processes combining membrane filtration with adsorption; ii) advanced oxidation process using ultraviolet (UV) and hydrogen peroxide (H2O2); iii) coagulation-flocculation combined with sand filtration; iv) combination of ozonation process, adsorption, and ultrafiltration (UF). This review paper discusses the selection of suitable treatment technology depends on several factors: i) a well-designed equipment, ii) cost-effectiveness of treatment method and iii) desired characteristics of the treated water. The review paper also presents solutions for treatment and reclamation of LWW.

In-situ removal of odorous NH3 and H2S by loess modified with biologically stabilized leachate

The loess regions distribute widely in Northwestern China, North America and Eastern Europe. For these regions, landfill is a suitable technology for solid waste treatment. However, as a landfill cover material, loess is not very effective in controlling the emission of malodorous gases. The present study modified loess with biologically stabilized leachate, and investigated the capacities and mechanisms of the modified loess to remove odorous NH3 and H2S. The removal rates of NH3 and H2S at different acclimation time, targeted gas concentrations and temperatures were measured. It was found that the NH3 removal rate of the modified loess was up to 0.08 μmol/(g·hr), which was 1.8 times that of the virgin loess. The H2S removal rate of the modified loess was up to 1.74 μmol/(g·hr), which was 1.25 times that of the virgin loess. The half-meter loess layer modified by biologically stabilized leachate achieved nearly 100% removal of H2S. The improvement of NH3 and H2S removal ability was mainly due to the enrichment of relevant microorganisms. This work proposed a novel method for in-situ control of malodorous pollutants in landfills in the loess regions, and proved that the in-situ removal of NH3 and H2S using the loess modified with biologically stabilized leachate is feasible and cost-effective.

Removal of organic pollutants (pharmaceuticals and pesticides) from sewage sludge by hydrothermal carbonization using response surface methodology (RSM)

AbstractBACKGROUNDConventional wastewater treatment plants (WWTPs) cannot degrade completely emerging pollutants such as pharmaceuticals and pesticides. The release of such contaminants through WWTP effluents or sludge disposal is of high environmental concern. Hydrothermal treatment has been adopted as alternative treatment technology for sludge to recover energy and valuable products. This study demonstrates the removal of inherent concentration levels of organic pollutants from the previous classes under variable reaction conditions, i.e. temperature, reaction time and sludge‐to‐water (%wt) ratio.RESULTSResponse surface methodology (RSM) was applied to model removal efficiency for the sum of detected pharmaceutical compounds and to evaluate the significant operational parameters. The results showed that higher values of temperature and time enhanced the percent degradation efficiency while sludge‐to‐water (%wt) ratio was not a significant factor affecting the removal process. The maximum removal efficiency of pharmaceutical residues reached 89.8% under the following conditions: 220 °C, 360 min reaction time, 7.50%wt sludge‐to‐water ratio. Additionally, hydrothermal treatment removed completely trace levels of detected pesticides, regardless of the applied conditions. RSM was also applied separately to those pharmaceuticals (i.e., amisulpride and amitriptyline) detected most frequently and at higher concentrations in sludge samples. Both compounds have been degraded at >90% using reaction temperatures from 205 to 220 °C and reaction time between 297 and 360 min with 7.5% sludge/H2O ratio.CONCLUSIONHydrothermal treatment is a suitable and promising technology for sewage sludge treatment for the efficient destruction of organic pollutants and the production of renewable hydrochars. © 2022 Society of Chemical Industry (SCI).

Evaluation of water quality index and geochemical characteristics of surfacewater from Tawang India

In this study,the water samples were collected from 31 sites of Tawang, Arunachal Pradesh, India (North-Eastern Himalaya), during the winter season to check the suitability of water for drinking and irrigation purposes.The study scientifically demonstrates the estimation of Water quality index (WQI) andhydrogeochemical characteristics of surface water samples by utilizing multivariate statistical methods. The main water quality parameters considered for this study were TDS, conductivity, salinity, pH, hardness, cations and anions. WQI was calculated in order to find out the deviation in the water quality parameters particularly with respect to BIS permissible limits.The major influencing factors responsible for the variation in these parameters were derived by using Principal component analysis (PCA) and Correlation matrix.To check the suitability of water for drinking purpose, hydrogeochemical facies and rock water interaction was derived by using well established methods such as Piper Plot (determine water type), WQI (Quality monitoring), and saturation index (for mineral dissolution). The results revealed that the silicate weathering was the main ionic source in comparison to carbonate weathering which is due to the higher dissolution capacity of silicate minerals.The results of the scattered plot between (Ca2+ + Mg2+)–(HCO3ˉ + SO42ˉ) versus (Na+ + K+)–Clˉ (meq/L) highlighted thation exchange occurs between Mg2+ and Ca2+ofsurface water with Na+ and K+of rock /soil. This means that calcium ion was getting adsorbed, and sodium ion was getting released. The Ca2+–Mg2+–HCO3ˉ, Na+–HCO3ˉand Na+–Clˉ type of surface water suggested permanent and temporary hardness respectively in the studied region. The dominant cations of this study were Na+ and Ca2+ while the dominant anions were HCO3ˉ and SO42ˉ. In order to check the suitability of water sources for irrigation, parameters like, Magnesium hazard (MH), Total hardness (TH), Permeability Index (PI), Kelly Index (KI), Sodium adsorption rate (SAR), Sodium percentage (Na%), and Residual sodium carbonate (RSC) were determined. The results showed that 93% of the samples had PI score < 75, which indicates the suitability of the water for irrigation. Also the WQI calculation showed an average WQI value of 82.49, amongst which 61% samples were in the range of 0–50 being considered as good for drinking, while 39% were catageorised as unsuitable for drinking showing a value of > 50. Hence the above findings reveal that geogenic activities play a major role in influencing the water quality of Tawang region. Hence suitable water treatment technologies or methods might be used to eliminate thenon desirable elements and minerals present in surface water.

Reduction of Retained Austenite in Tool Steels

Abstract Tools are devices for machining materials which must have different properties depending on their intended application. These properties are determined by the chemical composition and microstructure of the tool steel. The desired steel microstructure can be achieved with suitable heat treatment technology. During this heat treatment, the microstructure of the tool steel may develop various lattice structural transformations which in turn can cause internal stresses, cracks and distortions. One possible reason for these undesirable results may be the retained austenite. These effects are most pronounced in tool steels. In this study, the possibilities for reducing the amount of residual austenite during the heat treatment of tool steel is investigated.

Development and application of a contaminant transport model for groundwater remediation and reservoir protection: a case study from India.

The upper Kodaganar basin, located in Dindigul district of Tamil Nadu, India, is composed of hard rock terrain. Groundwater is the major source of domestic and irrigation needs and it is being contaminated by tannery wastewater that is discharged into the nearby Sengulam Lake. The main aim of this work was to develop a contaminant transport model using the total dissolved solids (TDS) concentration of groundwater measured in the basin. The model was developed to predict the fate of contaminant in the aquifer. The TDS concentrations in the wells ranged from 249 to 20,120mg/L, wherein extremely high values were observed in some of the severely contaminated wells. Three scenarios were proposed to predict the fate of the contaminant and to mitigate the effect of contaminant on groundwater receptors for the year 2020: scenario I: developed with the existing discharge conditions; scenario II: developed with discharge as per the standards; scenario III: developed with zero discharge. The results of this study showed that scenario III reduced the contaminated area from 12 km2 to 6 km2. The reduction in area for different concentration contours, namely 2000mg/L, 5000mg/L, 10,000mg/L, and 15,000mg/L, was 2 km2, 0.5 km2, 0.2 km2, and 0.1 km2, respectively, and the groundwater remediation was expected to take 2050years. Hence, there is an urgent need for the application of clean and resource efficienttechnologies in process industries, and the implementation of suitable wastewater treatment technologies to prevent ground water pollution in the region.

Artificial wetlands and floating islands: Use of macrophytes

Constructed wetlands, including floating islands, are a suitable technology for wastewater treatment. They are low cost and respectful with the environment, which is why they are significantly beneficial for agricultural irrigation systems. One of the limiting factors in structuring efficient constructed wetlands is the choice of plant species that can tolerate and eliminate contaminants. Macrophytes have an important role, since they allow their filtration, retention and absorption, among other processes. The objective of the work has been to show the diversity of emergent and aquatic species used for the treatment, highlighting species such as Typha latifolia, Typha doingness and Eichhornia crassipes, as species of constant use. In efficiency, they manage to eliminate nutrients and organic matter in excess, as well as toxic elements such as zinc, cadmium, lead, chromium, mercury, among others, in values between 15-95%. Some studies also address emerging pollutants, showing that wetlands successfully mitigate the presence of contamination by these micro-pollutants, eliminating paracetamol, ibuprofen, caffeine and antibiotics, among others, in values of 75-99%. Constructed wetlands are a frequent management practice for the mitigation of pollutants, the management of the biomass generated is an issue little explored and rarely considered. It is important to highlight several works where biomass is used to feed animals, such as fertilizers, to generate building blocks and production of bioenergy through biogas.

The strong promoting effects of thin layer Al2O3 on Fe[sbnd]Cu Fenton-like components: Enhanced electron transfer

The Fe(III)/Fe(II) redox cycle is the main factor limiting the effectiveness of Fe-mediated advanced oxidation processes (AOPs) for the degradation of organic pollutants. In this study, the promoting effects of thin-layer Al2O3 (t-Al2O3) between the frequently used FeCu components and the mesoporous silica support were studied to reduce Fe(III) to promote the activity of the Fenton-like catalyst. After modification by t-Al2O3, the mesoporous silicon-loaded FeCu catalyst removed 97% of Rhodamine B at pH 7, which was superior to the unmodified sample with a removal rate of 62.4% under the same conditions. Morphological characterization and X-ray diffraction patterns indicated that the Fe-Cu/t-Al2O3 active components were highly dispersed. Pyridine infrared spectra suggested that all of the acid sites were Lewis acids, and the t-Al2O3-loaded samples provided moderate/strong Lewis acids. The loading of t-Al2O3 between the FeCu complex and mesoporous silica support facilitated electron transfer during the Fe(III)/Fe(II) redox cycle by enhancing the dispersion of Fe-Cu/t-Al2O3 and the Lewis acidity. The results of this study provide insight into how t-Al2O3 promoted the interactions between the active components and silica support and how it can be used to aid in the selection of suitable wastewater treatment technologies.