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This study evaluated the coagulation/flocculation process using chitosan as a natural coagulant to concentrate suspensions of the cyanobacterium Synechococcus subsalsus and enable biogas production from concentrated biomass. The chitosan performance was tested and compared with the inorganic ferric chloride (FeCl3) coagulant. Using the liquid fraction of the coagulation/flocculation process in subsequent biomass cultivations proved viable, with similar growths in culture media with up to 80% of the liquid fraction. At pH 6 and 400 mg/L FeCl3, the biomass concentrated almost seven times, increasing the total suspended solids (TSS) of the suspension from 0.4–0.6 g/L to 2.6–4.0 g/L. With 80 mg/L chitosan and pH 7, the TSS concentration attained values in the range of 7.0–9.7 g/L, an increase of more than 30 times, clearly showing that chitosan has a much higher capacity for biomass concentration at a lower concentration. A ratio of 0.3 g chitosan/g dry mass of the biomass was established to reach the maximum densification. The production of methane from chitosan-densified biomass proved to be feasible. Chitosan-densified biomass showed a two-phase cumulative methane production when digested, with slower methane production and 23% lower methane yield after 30 days of digestion (207 NmL CH4/g CODi) compared to the biomass from cultivation (non-densified, 270 NmL CH4/g CODi). However, optimizing the digestion conditions of the densified biomass should increase the methane yield and reduce process time. [ABSTRACT FROM AUTHOR]

The electrical conductivity of traditional medical fibers was enhanced through in-situ polymerization of dopamine, resulting in the fabrication of a PET@PDA flocking fabric using electrostatic flocking technology. The response surface methodology was employed to optimize the parameters of the flocking process, and regression models were established to analyze the relationship between flocking process parameters and flocking density, specific surface area. An evaluation was conducted on the appearance, mechanical properties, cell compatibility, and blood compatibility of PET@PDA flocked fabric. The results demonstrate that PET@PDA10-2 flocking fabric exhibits high vertical orientation, significant porosity, excellent compression recovery performance (98.10% recovery rate under 50% strain), as well as favorable cytocompatibility and blood compatibility with remarkable coagulant promoting ability. Therefore, the electrostatically flocked PET@PDA fabric holds promising potential for applications in anticoagulant materials. [ABSTRACT FROM AUTHOR]

A novel composite coagulant, magnetic polymerized ferric magnesium chloride (MPFMC), was prepared based on traditional inorganic coagulants of polymeric ferric chloride (PFC). It was used to remove polystyrene (PS), a major component of microplastics that is easily suspended in water. The distribution of Fe species under different preparation conditions was investigated, and the physical and chemical properties of MPFMC were characterized using FTIR, XRD, SEM, and VSM. The effects of dosage, pH and temperature on the removal of PS by MPFMC and the floc structures were also investigated. PS removal was maximized when n(Fe) : n(Mg) = 4 : 1, n(OH)/n(Fe + Mg) = 0.4 and MFe3O4 : MFe = 2 : 1. The content of Fe(b), the most critical component of the iron salt coagulant, increased compared with that of PFC after the introduction of appropriate amounts of magnesium salt and Fe3O4. In addition, MPFMC has a wide adaptability to pH and temperature. When the dosage of MPFMC was 0.12 mmol L−1 (pH of 4.5–9.5, temperature of 19–34 °C, rapid stirring at 300 rpm for 2 min, slow stirring at 100 rpm for 10 min, and external magnetic field settling for 10 min), the coagulation performance was excellent, and the removal of PS was greater than 85%. The fractal dimension peak value of the flocs formed reached 1.87, and the floc structure was dense. In conclusion, the modification of introducing magnetic particles and magnesium salt into PFC has proven to be an effective strategy for improving the removal efficiency of microplastics by iron salt coagulants. [ABSTRACT FROM AUTHOR]

Using the high-speed motion acquisition system, we studied the settling process of the coal flocs under different addition interval time. The gray value and zeta potential of supernatant generally increased as the interval time increased, proving the effect of interval time on coal slime sedimentation. Furthermore, the interval time 25 s presented the smallest floc amount. The floc size and zeta potential were measured via the inverted fluorescence microscope and the micro electrophoresis, respectively. The interval time 25 s presented the fastest settling velocity. The floc amount in supernatant roughly decreased as the zeta potential increased. The settling velocity decreased with the settling time. The results can provide valuable insight into the development of technology for coal slime sedimentation. [ABSTRACT FROM AUTHOR]

The quartz sand-enhanced coagulation (QSEC) is an improved coagulation method for treating water, which uses quartz sand as a heavy medium to accelerate the sedimentation rate of flocs and reduce the sedimentation time. The factors that influence the QSEC effect and can be controlled manually include the quartz sand dosage, coagulant dosage, sewage pH, stirring time, settling time, etc., and their reasonable setting is critical to the result of water treatment. This paper aimed to study the optimal conditions of QSEC; first, single-factor tests were conducted to explore the optimal range of influencing factors, followed by response surface methodology (RSM) tests to accurately determine the optimum values of significant factors. The results show that the addition of quartz sand did not improve the water quality of the coagulation treatment, it took only 140 s for the floc to sink to the bottom, and the sediment volume only accounted for 12.2% of the total sewage. The quartz sand dosage, the coagulant dosage, and sewage pH all had a significant impact on the coagulation effect, and resulted in inflection points. A QSEC-guiding model was derived through RSM tests, and subsequent model optimization and experimental validation revealed the optimal conditions for treating domestic sewage as follows: the polyaluminum chloride (PAC) dosage, cationic polyacrylamide (CPAM) dosage, the sewage pH, quartz sand dosage, stirring time, and settling time were 0.97 g/L, 2.25 mg/L, 7.22, 2 g/L, 5 min, and 30 min, respectively, and the turbidity of the treated sewage was reduced to 1.15 NTU. [ABSTRACT FROM AUTHOR]

Petroleum pollution is an urgent and serious problem that has a negative impact on environmental safety and the state of the environment. Petroleum products that enter water resources cause a number of negative consequences, including water and soil pollution, reduced quality of natural ecosystems, as well as threats to biodiversity and human health. The purpose of this study is to assess the effectiveness of methods for treating surface wastewater of a machinebuilding enterprise from poll ution by petroleum products. In the course of the work, the results of cleaning the surface wastewater of the machine-building enterprise from pollution by petroleum products, samples of which were taken from the rainwater intake well at different depths - 30, 60 and 80 cm. A purification scheme has been developed and optimized, which includes the introduction of Al2(SO4)3 coagulant and A-19 flocculant into wastewater. Purification efficiency is achieved at about 95% at optimal reagent doses of 60-80 mg/L coagulant and 2-2.5 mg/L flocculant. The advantage of the conducted studies is the possibility of using the obtained data and methods for the analysis of wastewater with a similar composition of contaminants. It has been experimentally established that the simultaneous administration of reagents or the use of only one of them has lower efficiency and leads to insufficient purification of water from petroleum products. Neutralization of ion resistance contributes to the formation of coagulation structures, and to increase them it is recommended to use a flocculant to form and increase the size of aggregates. The results of the studies confirmed the prospect of using flotation to further separate the emerging petroleum flocculi, which allows to reduce the amount of reagents used and improve the efficiency of water treatment. The obtained data are important for practical application in the field of wastewater treatment from petroleum products at machine-building enterprises, contributing to the improvement of the quality of water resources and compliance with environmental safety requirements. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, persulphate and nanoscale zero-valent iron were activated by ultraviolet irradiation (PS/nZVI/UV), followed by formation of dynamic flocs with AlCl3–TiCl4 coagulant directly injected into a gravity-driven membrane (GDM) tank. Membrane fouling caused by typical organic matter fractions including humic acid (HA), HA together with bovine serum albumin (HA-BSA), HA combined with polysaccharide (HA-SA) and the HA-BSA-SA mixture at pH of 6.0, 7.5 and 9.0 were evaluated by specific flux and fouling resistance distribution. The results showed that GDM pre-layered with AlCl3–TiCl4 flocs exhibited the maximum specific flux, followed by AlCl3 and TiCl4. Pre-oxidation with 0.5 mM PS and 0.1 g nZVI under UV radiation for 20 min was beneficial to degrade HA and SA fraction with molecular weight >100 kDa and <30 kDa, and BSA fraction with <30 kDa. The presence of BSA attributed mostly to irreversible fouling, SA together with BAS could exacerbate irreversible fouling, while HA caused the least fouling. The irreversible resistance of a PS/nZVI/UV-GDM system was 62.79%, 27.27%, 58.03% and 49.68% lower than that of control GDM in the treatment of HA, HA-BSA, HA-SA and HA-BSA-SA, respectively. The PS/nZVI/UV-GDM system could achieve the highest foulants removal efficiency at pH of 6.0. Morphological observations confirmed the differences in biofouling layers in different water types. Over 30-day operation, the bacterial genera on the biofouling layer could affect the organic removals, while the type of organic matter that was present influenced the relative abundance of bacterial genera. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia y Educación (2707-3378) is the property of Duanys Miguel Pena Lopez and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The main purpose of this paper was to reveal the effect of aluminum (Al)-based coagulants on enhanced coagulation for the removal of algae and the synergistic optimization mechanism among different Al species. The formation, breakage, and regrowth processes of algal coagulation flocs formed by a series of monomeric Al-based coagulants (Al2(SO4)3, Al13, and Al30), Al13/Al30 composite coagulant and poly(diallyldimethylammonium chloride)/Al13 (PDADMAC/Al13) composite coagulant were studied. Results indicated that Al13 mainly employed a charge neutralization mechanism, which was conducive to the destabilization of algae and the regeneration of flocs, while Al30 mainly employed a sweep flocculation mechanism, which was conducive to the formation of algae and the strength of flocs. Meanwhile, the charge neutralization was the main mechanism during the algae coagulation process because it could effectively remove the soluble microbial products (SMP) component in the extracellular organic matter (EOM). Therefore, Al13 could achieve a higher coagulation performance than other monomeric Al-based coagulants. The Al13/Al30 composite coagulant could make up for the deficiency of the sweep flocculation mechanism in Al13 and charge neutralization mechanism in Al30, and achieve the best synergistic optimization performance at Al13:Al30-7:3. Additionally, PDADMAC, as a polymer, could further enhance the charge neutralization ability of Al13 at low dosages and the sweep flocculation ability of Al13 at high dosages, respectively. However, an excessive dosage would lead to charge reversal and thus reduce the coagulation effect. Therefore, controlling the dosage was key when using Al-composite coagulants. The findings of our research could offer a certain theoretical foundation for the development of inorganic polymer flocculants. [ABSTRACT FROM AUTHOR]

Cassia fistula (C. fistula) seed-derived coagulants have demonstrated substantial potential for treating dye-based wastewater. Such coagulants exhibit notable coagulating-flocculating activity and are environmentally friendly. However, recovering these natural coagulants from aqueous media poses challenges. In this study, we introduce a novel plant-derived magnetic coagulant that is a combination of C. fistula seed gum with magnetic spinel ferrite. This research includes a pilot-scale study to simulate full-scale textile wastewater treatment using this composite. Material characterisations revealed that spherical CoFe2O4 particles could be effectively coated with the active coagulant, C. fistula gum. The saturation magnetisation of the composite, measured at 54.11 emu/g, facilitates its convenient separation from aqueous solutions using an external magnetic field. Bench-scale studies showed that initial pH and coagulant dosage substantially affect the removal efficiency of colour and chemical oxygen demand (COD). In the pilot-scale study, the C. fistula-CoFe2O4 composite demonstrated promising coagulant properties. It achieved a colour removal percentage of 94.0 % with a volume of 30 L and a coagulant dosage of 12.3 g L-1 . Using this coagulation-flocculation process as a primary treatment step, possibly followed by biological or membrane methods, can help meet Vietnamese environmental standards. [ABSTRACT FROM AUTHOR]

To create raw materials with additional value, a range of raw materials from waste products from the mineral sector can be recycled. At the tertiary step of wastewater treatment, iron solid waste can be converted into inorganic coagulants. Steel waste can be converted into ferric chloride (FC) and poly ferric chloride (PFC), which are crucial for tertiary treatment of sewage water. The variables influencing the amount of FC and PFC were produced as (Fe2O3) were assessed, including pH, contact time, hydrochloric acid concentration %, and HCl flow rate. The generated FC and PFC were characterized using FTIR, XRD, XRF, and SEM as a new material that was later employed to treat wastewater. The highest removal percentage of turbidity, TSS, TOC, and TKN from tertiary treatment of sewage water with FC were, 92.7 %, 97.2 %, 88.2 %, and, 94.4 %, respectively. The highest removal percentage of turbidity, TSS, TOC, and TKN for tertiary treatment of sewage water were, 97.7 %, 98.4 %, 90.5 %, and, 96.8 %, respectively using PFC. In conclusion, FC and PFC made from steel waste should be used more widely in the tertiary treatment of sewage water, surface water, agricultural wastewater treatment since it is an affordable, high-quality coagulant and protection of environment. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs), as a new type of carbon material with complete molecular structure, have great application potential in the field of nanocomposites. In this study, carbon nanotubes were first surface modified to give them good hydrophilicity. Subsequently, the nanocomposite coagulant (PASS-T) with different modified CNTs (m-CNTs) contents was prepared by alkaline titration method. The CNT, m-CNT, PASS and PASS-T were characterized by FTIR, XRD and XRF. Then the coagulant was applied to oily sewage, and the coagulation results showed that the PASS-T (0.1%) had the best oil reduction rate (92%) and turbidity reduction rate (97%). Appropriate addition of m-CNT can increase the local concentration of coagulant at the molecular level, making the flocs of oily sewage larger. It can be found by SEM that PASS-T produces large and knotted flocs in oily sewage. Finally, the residual turbidity and oil removal rate of the different coagulants were statistically analyzed. [ABSTRACT FROM AUTHOR]

The wastewater treatment process for middle rank coal employed coagulation-flocculation technology with bio coagulants to efficiently reduce the concentration of contaminants. This method utilized Moringa oleifera L. seed powder as the main bio coagulant, in addition to papaya seeds (Carica papaya Linn.) and Ambon banana peel waste (Musa paradisiaca var.) as secondary bio coagulants, which are combined with the main bio coagulant. The aim of this study was to determine the characteristics and effectiveness of bio coagulant compounds obtained from plants and waste materials. The study objective was also to investigate the effectiveness of combining biocoagulants derived from Moringa oleifera L., Carica papaya, and Musa paradisiaca var. in treating coal effluent. Biocoagulant is a natural alternative to chemicals like aluminum sulfate (Alum) that are detrimental to the environment. It is present in the ecosystem and serves as a substitute for these hazardous substances. The results revealed that the optimal dosage for combining bio coagulants was 1 gram per liter, with a composition ratio of 2 parts primary bio coagulant to 1 part auxiliary bio coagulant. The analysis of water pollutants showed a reduction in turbidity and total suspended solid (TSS) by 99.26% and 99.11% respectively. Additionally, there was a decrease in the levels of heavy metals iron (Fe) and manganese (Mn) by 98.71% and 99.88% respectively. [ABSTRACT FROM AUTHOR]

The primary and secondary wastewater treatments from different sewage treatment plants are of great importance not only for removing pollutants but also for using treated water for different purposes. The latter involves using suitable coagulants and their optimal dosages for the treatment. Given this, the present study identified the most suitable coagulant for tertiary treatment and its optimal dosage to achieve the maximum total suspended solids (TSS) and biological oxygen demand (BOD) removal. We used six coagulants (alum, ferric chloride, polyaluminium chloride (PAC), Zetag4120, Mecafloc-25 and Rothfloc-27) and found that Zetag-4120 is the cost-efficient coagulant at varying coagulant dosage. We arrived at this conclusion based on several experiments using varying coagulant dosages. Furthermore, the regression prediction models for BOD and TSS removal for coagulant Zetag-4120 have been generated using statistical models and validated by calculating R² value, F-test and Lack-of-fit test using ANOVA. Optimization analysis suggests the optimal dosage, initial wastewater pH and settling time to be 1.86 mg/l, 6.73 and 89.12 min respectively. Furthermore, BOD and TSS removal efficiency values are 50.0% and 92.4% respectively. The treated wastewater has BOD and TSS equal to 12.27 and 5.66 mg/l respectively, conforming to the standard for re-usability of treated water for unrestricted irrigation. [ABSTRACT FROM AUTHOR]

Carbon fiber paper (CFP) is one of the most widely used gas diffusion layer materials for proton exchange membrane fuel cells (PEMFC) due to its excellent properties such as high conductivity, high strength, high air permeability and corrosion resistance. In this study, CFP was prepared using the phenolic resin (PF) in-pulp addition method. The effect of PF content on the properties of hot-pressed paper (HPP) and CFP was investigated. The results showed that when the dosage of polyethylene oxide (PEO) was 1.5 wt%, the flocculation effect of PEO on PF was basically complete, and the water filterability and retention of carbon fiber pulp were relatively optimal. After HPP was carbonized into CFP, the hydrophobicity, average pore size, porosity, and air permeability increased, while the resistivity and tensile strength decreased. With the increase of PF content, the tensile strength of CFP gradually increased, while the average pore size, porosity, air permeability and resistivity decreased. When the PF content was 250 wt%, the average pore size of CFP was 36.5 μm, the water contact angle was 127°, the porosity was 69.7%, the air permeability was 7.81 × 103 mL mm/(cm2·h·mmHg), the resistivity was 21.1 mΩ cm, and the tensile strength was 15.7 MPa. In addition, the CFP prepared using PF in-pulp addition method had a relativity uniform pore size distribution and high air permeability. Therefore, this work shows that the CFP prepared using this technique exhibits excellent comprehensive performance, and enables the manufacturing of CFP to be more efficient, low-cost, and environmentally friendly. [Display omitted] • Carbon fiber paper was prepared efficiently using the phenolic resin in-pulp addition method. • Polyethylene oxide exhibits strong adsorption ability on phenolic resin in carbon fiber pulp. • The melting temperature of phenolic resin is a critical point in the preparation process of carbon fiber paper. • Carbon fiber paper possesses a relatively uniform pore size distribution and high air permeability. [ABSTRACT FROM AUTHOR]

In this work, an innovative dual cross‐linking strategy for carboxylated nitrile butadiene rubber (XNBR) latex using epoxy‐modified calcium silicate particles is presented. In their role as dual cross‐linker, the particles are able to form covalent bonds (nucleophilic ring opening of epoxy moieties) as well as ionic cross‐links (calcium ions of the inorganic core) across the carboxylic acid groups of the rubber. To characterize the curing efficiency, thin elastomer films are prepared by using a conventional coagulant dipping process and their cross‐link densities, curing kinetics, and tensile properties are investigated as a function of the concentration of the cross‐linker and curing time. The results show that latex films containing 5 phr of epoxy‐functional particles give the highest tensile strength, which is further improved by pre‐vulcanizing the liquid latex compound at 60°C for 30 min. The latex formulations are stable over 3 days and the pre‐cured films exhibit a high resistance against gamma sterilization and subsequent accelerated aging. Moreover, sterile films do not cause any skin irritation or skin sensitization reactions, showing the high potential of epoxy‐functional particles in the production of accelerator‐free hypoallergenic gloves. [ABSTRACT FROM AUTHOR]

This study aims to improve COD, NH3‐N, and turbidity removal from Bingöl's leachate using a single‐reactor integrated electrocoagulation (EC)–coal‐based powdered activated carbon (CBPAC) process under various experimental conditions. In the EC‐CBPAC process, three stainless‐steel cathodes and three aluminum electrodes were connected to the negative and positive terminals of the power supply, respectively. The initial concentrations in the leachate were 1044 mg O2/L for COD, 204 mg/L for NH3‐N, and 57 NTU (or 71.25‐mg (NH2)2H2SO4/L) for turbidity, respectively. After a 40‐min EC‐CBPAC process, with a CBPAC dosage of 5 g/L and pH of 5 for COD and turbidity, and 9.5 for NH3‐N, the optimum removal efficiencies for COD, NH3‐N, and turbidity were achieved at 92%, 40%, and 91%, respectively. When the EC process was applied without CBPAC under the same experimental conditions, the removal efficiencies of COD, NH3‐N, and turbidity were 87%, 28%, and 54%, respectively. Before and after the EC‐CBPAC process, the Brunauer–Emmett–Teller (BET) surface area, pore volume, and mean pore diameter of the CBPAC were found to be (888 m2/g, 0.498 cm3/g, and 22.28 Å) and (173 m2/g, 0.18 cm3/g, and 42.8 Å), respectively. The optimum pseudo‐first‐order (PFO) rate constants for COD, turbidity, and NH3‐N were determined to be 3.15 × 10−2, 4.77 × 10−2, and 8.8 × 10−3 min−1, respectively. With the current density increasing from 15 to 25 mA/cm2, energy consumption, unit energy consumption, and total cost increased from 68.7 to 122.4 kWh/m3, 6.948 to 15.226 kWh/kg COD, and 0.85 to 1.838 $/kg COD, respectively. Practitioner points: EC‐CBPAC process has greater COD, NH3‐N, and turbidity removal efficiency than EC process.COD and turbidity achieved their optimum disposal efficiencies at 92% and 91%, respectively, at pH 5The most efficient disposal efficiency for NH3‐N was observed to be 40% at pH 9.5.EC‐CBPAC process increased removal efficiencies for COD, NH3‐N, and turbidity by 20%, 19%, and 38%, respectively, compared with EC alone.The turbidity, NH3‐N, and COD disposal fitted PSO model due to high correlation values (R2 0.94–0.99). [ABSTRACT FROM AUTHOR]

The main objective of this work is to analyze the possible use of banana peel waste as a natural coagulant and also to improve its coagulation effectiveness using an eco-friendly modification methodology the removal of synthetic water turbidity and river water purification. In this case, the modified banana peel powder hasan average particle size and diameters are 571 and 360 nm respectively. While the normal banana peel powder's size of particles and diameter were 978 and 602 nm, respectively. The effectiveness of the coagulation was examined at various pH values, dosages, sedimentation periods, and NaCl concentrations. With up to 90% turbidity removal, the ideal dose for modified banana peel was discovered to be 0.4 g/L. At small concentrations of less over 0.4 g/L, NaCl somewhat improved the coagulation performance; however, the activity decreased at higher concentrations, even when using the modified powder. In river water, banana peel powder act significantly hence reduced the color of the water, the total amount of dissolved and suspended solids, as well as the chemical and biochemical oxygen demand. However, for non-modified and modified powders, the turbidity reduction was only 75 and 83%, respectively. To look into and validate the coagulation mechanism, SEM and FT-IR analysis were done. Banana peel powder modified in this environmentally friendly way has a lot of potential as a cheap and accessible bio-coagulant and can likely help to decrease wastages. [ABSTRACT FROM AUTHOR]

Water is an essential element for human survival, yet many individuals still lack access to treated water to meet their basic needs. To mitigate this situation, alternative water treatment technologies that are accessible and easy to handle are being explored. Among these, the use of Moringa oleifera seeds as a natural coagulant and the application of a helically coiled tube as a flocculation unit have been studied. In this context, this study aimed to evaluate the turbidity removal efficiency using two different coagulants (Moringa oleifera and aluminum sulfate) in an alternative water clarification system. The system consists of a helically coiled tube flocculator (HCTF) coupled with a conventional decantation unit. It was observed that the coagulant solution from shelled seeds required a lower dosage to achieve efficiencies above 90% compared to the coagulant solution from seeds with shells. The optimal dosage was 30 mL/L of the coagulant solution from shelled seeds. This dosage resulted in high turbidity-removal efficiencies, ranging from 92% to 100%. The processing method of the seeds that yielded the highest efficiency in turbidity removal was the mortar and pestle, as opposed to a blender. The optimal configuration of the alternative water clarification system comprised using the lower HCTF in a horizontal orientation. The use of the alternative water clarification system, along with the natural coagulant, proves to be a promising alternative clean technology for water clarification in locations without access to conventional treatment, being efficient in turbidity removal. [ABSTRACT FROM AUTHOR]

Phosphorus pollution poses a significant challenge in addressing water contamination. The coagulant is one of the effective methods to remove phosphorus from wastewater. Abundant Al and Fe oxides in sludge residue make it have great potential to synthesize water treatment coagulants. However, the utilization of sludge residue for preparation of coagulant was seldom investigated. In this study, we fabricated a novel coagulant, polyaluminum ferric chloride (SM-PAC), using sludge residue as a raw material through acid leaching and polymerization processes. Characterization results confirm that the parameters of SM-PAC meet the specifications outlined in the national standard (GB/T 22627–2022). We investigated the effects of pH, dosage, initial phosphorus concentration, and contact time on the removal efficiency of SM-PAC. As anticipated, the prepared SM-PAC exhibited a significant efficacy in removing phosphorus, meeting the discharge standards set for municipal sewage. Furthermore, the adsorption kinetics analysis suggests that the predominant mode of phosphorus adsorption on SM-PAC is chemical adsorption. Furthermore, the SM-PAC was employed in the actual wastewater treatment plant and exhibited excellent efficiency in phosphorus removal. The utilization of SM-PAC can not only effectively address the issue of sludge disposal but also achieve the goal of "treating waste with waste." It is expected that the proposed method of reusing sludge residue as a resource can provide a sustainable way to synthesize a coagulant for phosphorus removal. [ABSTRACT FROM AUTHOR]

In this study, two by-products resulting from the processing of cherry (stems and pits) were used as natural coagulants to promote the valorization of these wastes and treat olive mill wastewater (OMW). The efficacy of the plant-based coagulants (PBCs) in the coagulation–flocculation–decantation process (CFD) was evaluated through the removal of turbidity, total suspended solids (TSS), total polyphenols (TPh), and dissolved organic carbon (DOC). The CFD process was demonstrated to be effective in turbidity and TSS reduction in OMW. Using cherry stems (CSs), these reductions were 65.2% of turbidity and 58.0% of TSS, while cherry pits (CPs) achieved higher reductions, 78.6% of turbidity and 68.2% of TSS. To improve the effectiveness of OMW treatment, mainly regarding the removal of TPh and DOC, the CFD process was complemented with the adsorption process (using bentonite clay). The adsorption capacity of bentonite was higher in acidic conditions (pH 3.0) and, with a dosage of 3.0 g L−1, reached 17.3 mg of DOC and 13.8 mg of TPh per gram of bentonite. Several adsorption isothermal models were assessed, and the Langmuir (r2 = 0.985), SIPS (r2 = 0.992), and Jovanovic models (r2 = 0.994) provided the best fittings. According to the optimal operational conditions defined throughout the present work, the combination of CFD and adsorption removals were as follows: (1) 98.0 and 91.3% of turbidity, (2) 80.8 and 81.2% of TSS, (3) 98.1 and 97.6% of TPh and (4) 57.9 and 62.2% of DOC, for CSs and CPs, correspondingly. Overall, the results suggest that cherry by-products can be used as low-cost natural coagulants and, when combined with another natural, abundant, and cheap material, such as bentonite clay, can be a sustainable alternative for treating OMW. [ABSTRACT FROM AUTHOR]

The physical and chemical water characteristics show different effects of extreme hydrological events. Such events can cause water supply interruptions in rural areas, such as Vlasotince, south-eastern Serbia. Therefore, this paper examines the values of selected parameters such as ammonia, nitrates, nitrites, turbidity, and chemical oxygen demand calculated from the amount of potassium permanganate, iron, manganese, temperature, pH value, colour, and aluminium at the measuring point of Vlasotince to identify changes in raw water quality parameters during extreme hydrological events. Over five years, fluctuations in water flow in the Vlasina River basin are considered. The interdependence between water flow and raw water quality parameters is assessed using a one-way analysis of variance and a post hoc Tukey Honestly Significant Difference test. Results reveal substantial differences in turbidity, chemical oxygen demand, nitrates, temperature, iron, colour, and manganese. Ammonia, nitrites, pH value, and aluminium exhibit no significant differences based on water flow intensity. Identifying and quantifying risk factors affecting water supply during extreme hydrological events allow for a more appropriate response to given challenges and the organisation of work in rural water supply systems. [ABSTRACT FROM AUTHOR]

Whether the oilfield sewage index can reach the reinjection specification is a crucial issue that is urgently need to be solved in polymer flooding systems. Thus the coagulability and floc morphology development of dual coagulants was systematically studied in different pH oily wastewaters. Acidification improved the deprotonation ability of coagulant. Hydrophobic associative polyaluminum silicate-poly dimethyl diallyl ammonium chloride (PASSC-PD) resolved the problem of excessive acid addition. The dual coagulants prepared not only preserved the high charge density of polyaluminum silicate (PASS) itself but also made it have the hydrophobic association and strong bridging ability. Besides, PASSC-PD was compared with hydrophobic associative polyaluminum silicate (PASS-C), PASS, and poly dimethyl diallyl ammonium chloride (PDMDAAC) pertaining to the polymer flooding oily sewage of Daqing Oilfield. The coagulation result demonstrated that PASSC-PD exhibited more advantageous turbidity and oil removal efficiencies than PASS-C, PASS, and PDMDAAC. The floc morphology result showed that adding dual coagulant made the petal-like floc of oily sewage larger at the pH value of 6. Furthermore relevant results evidenced that the coagulant had more successful fruits of turbidity removal of 96.5% and oil removal of 96.3% under weak acid conditions. These can satisfy the reinjection condition of oily sewage. [ABSTRACT FROM AUTHOR]

Design of new drugs is a challenging process: a candidate molecule should satisfy multiple conditions to act properly and make the least side‐effect—perfect candidates selectively attach to and influence only targets, leaving off‐targets intact. The amount of experimental data about various properties of molecules constantly grows, promoting data‐driven approaches. However, the applicability of typical predictive machine learning techniques can be substantially limited by a lack of experimental data about a particular target. For example, there are many known Thrombin inhibitors (acting as anticoagulants), but a very limited number of known Protein C inhibitors (coagulants). In this study, we present our approach to suggest new inhibitor candidates by building an effective representation of chemical space. For this aim, we developed a deep learning model—autoencoder, trained on a large set of molecules in the SMILES format to map the chemical space. Further, we applied different sampling strategies to generate novel coagulant candidates. Symmetrically, we tested our approach on anticoagulant candidates, where we were able to predict their inhibition towards Thrombin. We also compare our approach with MegaMolBART—another deep learning generative model, but exploiting similar principles of navigation in a chemical space. [ABSTRACT FROM AUTHOR]

The aim of this research was to valorize waste (sludge) from a drinking water treatment plant as a coagulant in the removal of dyes (methylene blue and crystal violet) from water and to prevent environmental issues associated with sludge storage. To accomplish this purpose, the response surface methodology based on a central composite design with five levels was implemented. In order to enhance the efficacy of the coagulation–flocculation process, three key operational variables were considered for optimization: the pH, coagulant dosage (mg/L), and initial dye concentration (mg/L). To achieve this, a quadratic polynomial model was established. According to the mathematical model that has been developed, it is predicted that the highest efficiency for removing dyes is 94.44%. This maximum effectiveness is reached when the pH is adjusted to 12.04, the coagulant dose is set at 87.044 mg/L, and the dye concentration of MB is maintained at 2.955 mg/L. Conversely, the best dye removal of CV was attained at 100% under the following conditions: pH = 12.045, a coagulant dosage of 2.955 mg/L, and a dye concentration of 2.955 mg/L. The R2 (98.44% and 95.80% for MB and CV, respectively) validated both models. In this work, the coagulant was characterized by the surface charge, FTIR, BET, and SEM analysis. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop a photothermal material modified with carbonization and ZnCl2 impregnation and supported by polyvinyl alcohol (PVA) for water purification using the waste coffee grounds. Scanning electron microscopy (SEM) characterization of the prepared material revealed that a significant surface modification was achieved due to the carbonization and ZnCl2 impregnation. X-ray diffraction analysis (XRD) pattern of the samples showed two broad peaks at 18.4° and 22.2°, this is due to the crystal planes of β-crystal phase structure, which indicates the existence of strong hydrogen bonds between the micro-structures and therefore less suspectable to chemical attack. Additionally, thermogravimetric analysis (TGA) result suggests a slight mass reduction between the temperature range of 65–75 °C implying the thermal stability of the prepared material. The produced modified material had a photothermal conversion efficiency of 74% and could produce vapor at a rate of 1.12 kg/m2h under 980 W/m2 irradiation at 1 sun. A significant reduction in Cu2+ ion concentration (83%), turbidity (91%), total dissolved solids (TDS) (61%), microbial load (95.6%), and total hardness (41.2%) were achieved. Therefore, waste coffee grounds can be considered as a future eco-friendly and low-cost candidate for water purification. [ABSTRACT FROM AUTHOR]

Background: Despite a range of available treatments, it is still sometimes challenging to treat patients with severe post-partum hemorrhage (sPPH). Objective: This study evaluated the efficacy and safety of recombinant activated factor VIIa (rFVIIa) in sPPH management. Methods: An open-label, multi-center, randomized controlled trial (RCT; NCT00370877) and four observational studies (OS; OS-1 (NCT04723979), OS-2, OS-3, and OS-4) were analyzed regarding efficacy (need for subsequent invasive procedures, including uterine compression sutures, uterine or iliac artery ligations, arterial embolization, or hysterectomy) and safety (incidence of thromboembolic events (TE) and maternal mortality) of rFVIIa for sPPH. The RCT, and OS-1 and OS-2, included a control group of women who did not receive rFVIIa (with propensity score-matching used in OS-1 and OS-2), whereas OS-3 and OS-4 provided descriptive data for rFVIIa-exposed women only. Results: A total of 446 women exposed to rFVIIa and 1717 non-exposed controls were included. In the RCT, fewer rFVIIa-exposed women (50% [21/42]) had an invasive procedure versus non-exposed women (91% [38/42]; odds ratio: 0.11; 95% confidence interval: 0.03–0.35). In OS-1, more rFVIIa-exposed women (58% [22/38]) had an invasive procedure versus non-exposed women (35% [13.3/38]; odds ratio: 2.46; 95% confidence interval: 1.06–5.99). In OS-2, 17% (3/18) of rFVIIa-exposed women and 32% (5.6/17.8) of non-exposed women had an invasive procedure (odds ratio: 0.33; 95% confidence interval: 0.03–1.75). Across all included women, TEs occurred in 1.5% (0.2% arterial and 1.2% venous) of rFVIIa-exposed women and 1.6% (0.2% arterial and 1.4% venous) of non-exposed women with available data. Conclusions: The positive treatment effect of rFVIIa on the RCT was not confirmed in the OS. However, the safety analysis did not show any increased incidence of TEs with rFVIIa treatment. [ABSTRACT FROM AUTHOR]

Soft cheeses are coagulated milk products obtained through acidification or applying a combination of acids and heat. In this research, in order to improve technological characteristics, the effects of different coagulants (salt and acids) and process parameters (temperature and homogenization pressure) on the organoleptic, textural, and functional characteristics of soft (unripened) cheese were investigated. The results revealed significant differences between cheeses coagulated with acid and mineral salt regarding protein recovery, fat content, and moisture content (p <.05). Acidic coagulants (74%–94%) resulted in higher cheese yield compared to mineral salt (66%–88%). Texture analysis indicated that the cheese produced with acetic acid had a firmer texture, while samples treated with citric acid exhibited better cohesiveness. Cheeses produced with minerals displayed more acceptable organoleptic characteristics regarding flavor, odor, and texture. This study offers valuable technological insights into cheese production with the highest yield and maximum acceptability. [ABSTRACT FROM AUTHOR]

This study investigated the use of natural extracts as bio-coagulants for water treatment and purification. The utilization of natural materials represents important progress in sustainable environmental initiatives, and their application is directly associated with improved quality of life due to their low toxicity, cost-effectiveness, and naturally renewable properties. Therefore, three plant species were identified, and their effectiveness was evaluated in the laboratory on surface water samples: Moringa oleifera (MO), Cicer arietinum (CA), and Pinus roxburghii (PR). Water samples were collected from the River Kunhar, Garhi Habibullah (Mansehra) for laboratory analysis. A combined treatment (coagulation and filtration) was found to be more efficient compared to direct filtration or coagulation alone. The highest turbidity removal of 99.17 percent, solids reduction of 93.21 percent, hardness reduction of 67.35 percent, and total coliform removal of 86.13 percent were achieved for the filtered water samples treated with MO. CA provided the maximum chloride reduction of 54.85 percent compared to the other two. These extracts slightly affected the acidity, alkalinity, pH, and conductivity of water samples. However, a slight increase in biological and chemical oxygen demand was found in treated water. Among the three natural coagulants, MO caused a significant increase in organic matter. This problem can be avoided by using the purified form of active coagulating agents rather than crude extract. This research shows the effectiveness of MO for surface water treatment and also illustrates the great potential of CA and PR as promising bio-coagulants for the treatment of polluted surface water samples. [ABSTRACT FROM AUTHOR]

The research aims to determine the effect of adding carrageenan and citric acid on the characteristics and shelf life of Moringa leaf jelly drinks. The experimental method was a completely randomized design with two factors: carrageenan concentrations (0.2%; 0.3% and 0.4%) and citric acid concentrations (0.1% and 0.2%). The parameters tested were crude fiber, total acid, antioxidant activity, mineral content, pH, viscosity, turbidity, color, and organoleptic (aroma, taste, texture, and color). The results showed that the interaction of the addition of carrageenan and citric acid had a significant difference in total acid, pH, mineral content, and viscosity but had no significant difference in crude fiber, antioxidant activity, turbidity, and organoleptic properties. The addition of 0.4% carrageenan and 0.1% citric acid is recommended as the best quality with a crude fiber 19.66%; total acid 2.63%; pH 3.14; Ca 275.19 ppm, Zn 30.71 ppm; Fe 1.44 ppm; antioxidant activity 63.69%; viscosity 17.73 cps; turbidity 114.67 ntu; slightly sour; orange in color and has an easily aspirated or semi-solid texture. The jelly drinks were stored using hot-filled PET bottles for 12 days at 10°C and 30°C. The calculation results of the Arrhenius model selected the pH value parameter as a critical parameter to determine the shelf life of the jelly drink, and the best treatment was 23 days at 10°C and 10 days at 30°C. [ABSTRACT FROM AUTHOR]

The study aims to analyze the effectiveness of wastewater treatment by using Carica papaya seeds as bio coagulants to diminish total suspended solids (TSS) and excess phosphate. This method has some advantages because it does not use chemical materials, is simple to apply, and is safe for the environment and human health. The wastewater samples were taken from an active laundry site in Palembang City, South Sumatra Province of Indonesia. The study found that the best dosage of coagulant was 3 g for the wastewater samples. The pH and BOD parameters showed slight changes after treatment, with pH 7.63–7.19 and 33–27 mg/L values, respectively. The TSS removal efficiency ranged from 9.3 to 15.6%, while the COD and phosphate removals were obtained from 11.7 to 39.3% and 56.3 to 68.4%, respectively. The treated TSS, COD, and phosphate concentrations have met the Indonesian domestic wastewater quality standard and environmental protection organization (EPO) guidelines. In addition, the statistical analysis and t-test showed significant differences (p < 0.05) for before and after treatment data of all parameters. The ANOVA test showed significant differences (p < 0.05) for all parameters among the three treatments. Overall, the study indicated that C. papaya seeds are promising materials that are eco-friendly and useful to treat laundry wastewater. [ABSTRACT FROM AUTHOR]

Chitosan, chitosan-moringa seed powder, and chitosan-moringa seed powder-bentonite composite films were fabricated by solvent casting method. The texture and the color of the chitosan films changed in the presence of moringa seed powder and bentonite. Moringa seed powder decreased the tensile strength of the films, whereas bentonite improved the tensile strength of the films when its concentration was below 15 wt%. All the films could efficiently remove turbidity from model turbid water - prepared by dispersing kaolin in water. A marked increase in turbidity coagulation was observed when moringa seed powder was incorporated into the chitosan film. Films with 15 wt% moringa seed powder could remove 73% in 3 h, whereas chitosan film alone removed 53% in 3 h. Further enhancement of turbidity removal efficacy was observed when bentonite was incorporated into the films along with the moringa seed powder. Films with 15 wt% moringa seed powder and 10 wt% bentonite removed 83 and 96% turbidity in 3 and 12 h, respectively. Furthermore, these films could be reused several times. The films with the above composition were tested for turbidity settlement for five cycles. In the 5th cycle, the films could remove 85% turbidity without undergoing any breakage. [ABSTRACT FROM AUTHOR]

The object of the study is the process of purifying natural waters using coagulants of natural and industrial origin. The subject of the study is the analysis of the effectiveness of coagulants of natural and industrial origin. Today, there is great interest in finding alternative methods of water purification that would be more economical and environmentally friendly. The availability of clean and safe water is especially important during times of martial law. Coagulants of natural origin can be an affordable and effective means of water purification and disinfection. One of the important advantages is availability, which indicates the possibility of becoming an alternative to chemical coagulants. Thus, there is a need to study the possibility of using natural coagulants both on an industrial scale and in emergency conditions. This study presents a characterization of existing coagulants of natural origin, an analysis of the effectiveness of their use, comparison with chemical analogues, as well as an analysis of the effectiveness of using Moringa oleifera as a natural coagulant. During the work, two coagulants were synthesized from red mud from aluminium production. A comparative analysis of coagulants synthesized from red mud, Moringa oleifera, aquatone and aluminium sulphate was carried out. All reagents were used to remove turbidity and other impurities. The studies were carried out 3 times in different seasons of the year. All results were compared to determine the most effective coagulant and its dose. As a result, it was found that all of these coagulants can be used and reduce water treatment costs at local water treatment plants. The natural coagulant can be used in areas where there is no access to a central water supply, especially in war zones. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of coagulant type in coagulation, flocculation and sedimentation processes and membrane pore size on the performance and economic aspects of water reclamation from UASB reactor effluent. The methodology involved laboratory-scale experiments using two different coagulant types (a modified tannin coagulant, TANm, and a polyaluminum chloride, PACl) and membrane filtration tests with microfiltration (MF) and ultrafiltration (UF). Compared to PACl, TANm had a smaller effect on the pH, consumed less alkalinity, and generated less sludge. However, PACl was more efficient in removing turbidity (89–97%), organic matter (70–72%), and phosphorus within the dosage range of 25 to 100 mg.L−1. Both membranes achieved high removal rates for turbidity and organic matter. Despite the higher flux decay, the MF system could have higher operating flux and lower fouling resistance. The operating costs were higher for the C/F systems, which was attributed to the cost of coagulants and sludge disposal. The system with MF membranes had a lower total cost, and the estimated payback period for the investment was between 0.73 to 0.24 years, based on the values charged for reuse water. This information can be used to optimize the design and operation of UASB-based water reclamation systems. [ABSTRACT FROM AUTHOR]

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Coagulation–flocculation is one of the most mature and effective process, which can remove most of the colloids. The objective of this study was to investigate a treatment for denim-washing wastewater by coagulation–flocculation and Fe/garnet filtration to evaluate the potential use of the sludge produced. The reaction time, stirring rate, dose, and coagulant agent using Ca2+, Mg2+, and Fe2+ as chlorides on the % removal of color, chemical oxygen demand, and turbidity were evaluated using an experimental design 32. The best chemical oxygen demand (49% of these low efficiencies may be related to chloride interferences), color (84.6%), and turbidity removal (82.3%) efficiencies were achieved at a dose of 1.4 g/L Ca2+, time of 20 min, and shaker speed of 50 rpm. Under these conditions, Ca(OH)2 commercial (Calidra® at 75–85%) was also tested, removing chemical oxygen demand, turbidity, and color by 67, 97, and 93%, respectively, at 1.4 g/L Ca2+. The effluent from the garnet filtration process was characterized, the pH was reduced from 11.8 initial to 7.7 final, and removals of 59.0% total organic carbon, 20.5% chemical oxygen demand, and 28.6% color. The effect of sludge from the coagulation–flocculation process with Ca(OH)2 was studied in Lactuca sativa seed. The life cycle assessment concluded that the treatment reduced the midpoint impacts of the environmental category indicators, such as freshwater eutrophication, marine eutrophication, freshwater ecotoxicity, marine ecotoxicity, human noncarcinogenic toxicity, land use, and mineral resource scarcity. Treated wastewater can be reused in the same process for denim washing. [ABSTRACT FROM AUTHOR]

Considerable attention is paid to improving the environmental safety of additive manufacturing. Manufacturing of articles from titanium using additive technologies (powder metallurgy) is characterized by a high water consumption, and, thus, a large amount of wastewater generated. The paper presents the main trends of using titanium compounds as coagulants for the treatment of natural water (treatment to industrial water grade) and wastewater from additive manufacturing of articles from titanium. It was ascertained that in the processes of wastewater and recycled water treatment, titanium-containing coagulants are much better that the traditional coagulants based on aluminium and iron salts. Treatment of water from surface sources to industrial water grade using titanium coagulants is also highly efficient, and the residual concentrations of pollutants are on average 2.0 - 3.0 times lower than when using the traditional reagents. The use of titanium salts as coagulants allows an average 2-fold reduction of reagent consumption. Coagulation sludge (sediment) forming in the course of water treatment is titanium dioxide and can be used in future as a raw material in different industries. [ABSTRACT FROM AUTHOR]

A hybrid baffled flocculator (HBF) is employed in this study in an effort to lower the footprint area and enhance the quality of drinking water. The process known as hydraulic mixing with media is less expensive than expanding a water treatment facility. To evaluate this technology, we use a pilot plant equipped with baffles loaded with packing material. Plastic, foam, and gravel have all been tested as turbidity-removing media. The experimental facility was designed to be similar to a traditional water treatment plant located in Benha City, Egypt. Hydraulic mixing is used in place of rapid flash mixing and gentle mechanical mixing. To assess the removal and hydraulic efficiency, this study compares the hydraulic model with and without media. Many effective parameters have been studied like media type, alum dose, and detention time. Results show that the hydraulic efficiency of the reg test is increased by packing material. Gravel has the highest average of 50% elimination efficiency for T = 18 min and alum dose = 26 P.P.m. Plastic has the second-highest turbidity removal efficiency, with an average of 45%. Finally, employing foam reduces turbidity in the Nile River by an average of 33%. Conversely, the average percentage removal while employing vertical baffles alone without media is 28%, the percentage of turbidity that was removed at varying alum doses varies from 14 to 33%, and the highest percentage of removal is achieved with a 30 P.P.m alum dosage. In addition, the average percent removal of foam, plastic, and media is 30%, 36%, and 43%, respectively. [ABSTRACT FROM AUTHOR]

This review describes the mechanisms of natural coagulants. It provides a good understanding of the two key processes of coagulation-flocculation: adsorption and charge neutralization, as well as adsorption and bridging. Various factors have influence the coagulation/flocculation process, including the effect of pH, coagulant dosage, coagulant type, temperature, initial turbidity, coagulation speed, flocculation speed, coagulation and flocculation time, settling time, colloidal particles, zeta potential, the effects of humic acids, and extraction density are explained. The bio-coagulants derived from plants are outlined. The impact of organic coagulants on water quality, focusing on their effects on the physicochemical parameters of water, heavy metals removal, and bacteriological water quality, is examined. The methods of extraction and purification of plant-based coagulants, highlighting techniques such as solvent extraction and ultrasonic extraction, are discussed. It also examines the parameters that influence these processes. The methods and principles of purification of coagulating agents, including dialysis, freeze-drying, ion exchange, electrophoresis, filtration, and centrifugation, are listed. Finally, it evaluates the sustainability of natural coagulants, focusing on the environmental, technical, and economic aspects of their use. At the end of this review, the readers should have a comprehensive understanding of the mechanisms, selection, extraction, purification, and sustainability of plant-based natural coagulants in water treatment. [ABSTRACT FROM AUTHOR]

Textile industries are water intensive and the effluent generated contains salts, dyes, and heavy metals as well as having a high biological oxygen demand (BOD) and chemical oxygen demand (COD), therefore it must be treated before being discharged into the aquatic environment to prevent its contamination. Electrocoagulation (EC) is a promising technique to treat domestic and industrial effluent, where in situ coagulants are produced by sacrificial dissolution of the anode by application of an electric current across the electrodes. The effect of punched-hole electrodes on the performance of EC—color removal efficiency (CRE), electrical energy consumption (EEC), and operating cost (OC)—was studied by varying the number and diameter of holes in the electrode. It was observed that the use of punched electrodes resulted in higher CRE, lower EEC, and lower OC as compared with plane electrodes. The difference in CRE obtained using plane and punched electrodes was found to increase with an increase in current. The effect of punched-hole electrodes on the treatment of real dye effluent was studied and COD removal of 78.79% was obtained using punched-hole electrodes as compared with 69.30% using plane electrodes. The EEC and the OC were found to be 0.5 kW·h/m3 and US$0.424/m3, respectively, for punched-hole electrodes. [ABSTRACT FROM AUTHOR]

High levels of heavy metals in industrial wastewater pose a significant environmental concern due to their toxicity to living organisms and ecosystems. Traditional techniques that use chemical coagulants to eliminate heavy metals from industrial wastewater have proven effective. However, the use of chemical coagulants produces sludge that is highly toxic and requires careful management. On the other hand, natural coagulants offer a cost-effective and sustainable alternative that is safer to handle, locally available, and potentially useful for resource recovery. These benefits make natural coagulants a promising substitute for chemical coagulants. This study aimed to investigate the performance of combining Date stone powder (DSP) and aluminum chloride (AlCl3), to remove heavy metals from industrial wastewater efficiently. Through an optimization process of DSP/ AlCl3 dosage and pH, the study sought to determine the optimal conditions for heavy metal removal. The main findings indicate that a DSP/AlCl3 dosage of 7:1 (g/g) was the most effective coagulant dosage, resulting in high removal efficiencies for COD (88.56%), color (89.56%), TSS (99.00%), NH3-N (92.50%), Mn (94.10%), Fe (95.47%), Zn (93.57%), Al (88.42%), and Ni (93.3%) at pH 8. Interestingly, the results of pH optimization showed that no pH modification was necessary, as it already achieved high removal efficiencies for COD (84.57%), color (88.94%), TSS (99.00%), NH3-N (92.25%), Mn (92.66%), Fe (90.57%), Zn (95.59%), Al (99.00%), and Ni (93.33%). This study demonstrates that the hybrid DSP/AlCl3 coagulation method can be an effective and sustainable solution for removing heavy metals from industrial wastewater. However, further research is necessary to assess its scalability and potential limitations. [ABSTRACT FROM AUTHOR]

Since the last decades, water stress challenges caused by climate change have posed a significant concern for the treatment and re-use of treated wastewater. Conventional treatment methods employ chemicals as coagulants-flocculants, which pose a serious threat. Hence, it has led to a gradual increase in the use of natural plants as promising safe alternatives. In the present work, the Austrocylindropuntia subulata plant was used for the first time as a coagulant-flocculant for wastewater treatment. The raw chlorenchyma powder of the plant was characterized by SEM, FTIR, and EDX, the results showed a very strong resemblance with the composition of the Opuntia ficus indica. The biocoagulant-flocculant was obtained by simple extraction using distilled water. An optimization dose test demonstrated that a mass of 0.1 g decreases approximately 99% of turbidity. After a year of storage, the raw powder retained the same efficiency. The extract's coagulant-flocculant properties remained stable after three months of storage, but it developed an unpleasant odor and a brownish color due to microbial oxidation of organic components. [ABSTRACT FROM AUTHOR]