Removal Efficiency Of Wastewater Research Articles

Poly O-toluidine-coated acetic acid modified eggshell-chitosan with ZnFe2O4 nanoparticles as a new and promising sorbent nanocomposite for rapid removal of toxic dyes such as Brilliant Green and Acid Red from the aquatic environment

The conversion of organic waste into valuable commodities is essential for safeguarding the environment and promoting the sustainable development of the economy. This investigation centres on the production of Zinc ferrite nanoparticles (ZnF NPs), modified eggshells (MES) impregnated with chitosan (CS) and coated with poly ortho-toluidine P(OT) nanocomposites (NCs). This synthesis involves a quaternary composition denoted as P(OT)/MES/CS/ZnF NCs, achieved through chemical polymerization techniques. The resulting NCs were characterized and applied for the removal of Brilliant Green (B.GR) and Acid Red (A.RE). Four distinct compositions, namely pure P(OT), binary P(OT)/MES, ternary P(OT)/MES/CS, and quaternary P(OT)/MES/CS/ZnF NCs, were synthesized. The outcomes revealed that the quaternary P(OT)/MES/CS/ZnF NCs exhibited the highest adsorption capacities for B.GR and A.RE at)27.03 and 142.8 mg−1(, respectively. The findings revealed that the most favorable parameters for the removal of A.RE were attained at a pH of 2, using 15 mg of P(OT)/MES/CS/ZnF NCs at a concentration of 25 mg/L for a duration of 120 min. On the other hand, when it comes to removing B.GR, the best results were shown while using 15 mg of P(OT)/MES/CS/ZnF NCs at a concentration of 5 mg/L for 120 min, specifically at a pH of 6. The greatest real wastewater removal efficiencies for A.RE dye and B.GR dye, respectively, were found to be 99.5% and 97.6% under these operating circumstances. These optimal quaternary NCs demonstrated the ability to be regenerated four times without significantly compromising their adsorption properties and exhibited a remarkable capacity to remove 96–98% of dyes from real polluted water. Through the use of regression data and a pseudo-second-order model, the adsorption kinetics were explained, with R2 values of 0.994 for A.RE and 0.993 for B.GR, respectively. Thermodynamic parameters of dye adsorption by the NCs affirmed the fact that adsorption occurs spontaneous and have endothermic nature. This study underscores an effective synthesis approach applicable for large-scale production of new adsorbents for water treatment purposes.

Boosting wastewater treatment and CO2 bioremediation with Nile River microalgae: Resilience to simulated smoke and enhanced biomass production

This study investigated the potential of Nile River microalgae for treating wastewater under simulated air pollution conditions. We evaluated microalgal growth and nutrient removal efficiency in wastewater with and without microalgal inoculation. Results demonstrated enhanced algal growth rates in all wastewater samples, with maximum chlorophyll (a) concentrations reaching 3093.2 μg/L and 4157.4 μg/L, respectively. This suggests efficient utilization of organic pollutants, with nutrient removal exceeding 90 % efficiency. Notably, Scenedesmus sp. emerged as the most resilient species, achieving the highest biomass production (735.5 mg/L) at a moderate CO2 concentration (16.6 mg/L). Interestingly, optimal CO2 concentrations enhanced the highest growth rate by 0.84 day−1, demonstrating the potential for simultaneous wastewater treatment and CO2 bioremediation. These findings highlight the promise of Nile River microalgae, particularly Scenedesmus sp., for sustainable wastewater treatment even in polluted environments, offering a dual benefit of environmental remediation and bioresource production.

Applications of bismuth-based nanoparticles for the removal of pollutants in wastewater: a review

This review discusses the characteristics and synthesis methods of Bi-based NPs. It delves into the removal efficiency in wastewater, emphasizing traditional/emerging strategies to enhance the performance, mechanisms, toxicology, and challenges.

Enhancement of carbon nanotubes on microalgal-fungal consortium formation and wastewater treatment

As a promising material with an efficient light capture capability, a low amount of carbon nanotubes can affect growth and photosynthesis by regulating microalgal cells, thereby enhancing the pollutant removal efficiency in wastewater. In this study, microalgal-fungal consortia of Chlorella vulgaris and Ganoderma lucidum were developed with different types and concentrations of carbon nanotubes. The treatment effect of microalgal-fungal consortia on simulated digestate was also studied. The results demonstrate that 1.5 mg/L of carboxylated multi-walled carbon nanotubes remarkably promoted the formation, growth and photosynthesis of consortium. The dry weight and chlorophyll a content reached 19.3 ± 0.53 mg/symbiont and 27.3 ± 0.52 μg/L, respectively. Moreover, the removal efficiency of chemical oxygen demand, total nitrogen, total phosphorus and tetracycline hydrochloride were 94.1%, 65.5%, 61.9% and 96.2%, respectively. Overall, these findings suggest a promising future for the use of carbon nanotubes in wastewater treatment by regulating microalgal-fungal consortia.

Characterization of the Nitrogen Removal Potential of Two Newly Isolated Acinetobacter Strains under Low Temperature

Excess nitrogen and phosphorus in the water causes several ecological problems for nutrients. Biological nitrogen removal is an economical and efficient way to prevent excessive nitrogen in the environment. For most areas of China, temperatures are usually lower than 20 °C except during the summertime. It is necessary to discover microbes that can efficiently remove nitrogen at low temperatures. In this study, two Acinetobacter strains were isolated from a sample in a wastewater tank in Taizhou for their capabilities to remove NO3−–N and NO2−–N at 15 °C. Heterotrophic nitrification experiments showed that both strains could efficiently remove nitrogen from the culture medium. The maximum removal rates of NH4+–N were 3.15 mg/L·h and 4.74 mg/L·h for heterotrophic nitrification by the strains F and H, respectively. Strain H grew faster and removed both nitrite and nitrate more efficiently than strain F. Genome sequencing showed that strains F and H could be classified into Acinetobacter johnsonii and Acinetobacter bereziniae, respectively. NO2−–N (100 mg/L) was completely removed in 3 days by strain H. The maximum NO3−–N removal rate was 3.53 mg/L·h for strain F. When strain H was cultured in a broth with 200 mg/L NO3−–N, 97.46% of NH4+–N (200 mg/L) was removed in 5 days, and the maximum NH4+–N removal rate was 4.04 mg/L·h. Genomic sequence analysis showed that both the strains lacked genes involved in the denitrification pathway that transforms NO3− into N2. This implies that nitrate or nitrite is removed through the nitrogen assimilation pathway. Genes responsible for nitrate assimilation are clustered together with molybdopterin cofactor biosynthesis genes. Strain H contains fewer resistance genes and transfer elements. All the above data demonstrate that strain H is a promising candidate for nitrogen removal at lower temperatures. But there is still a lot to be done to systematically evaluate the potential of A. bereziniae strain H in treating wastewater at a pilot scale. These include the long-term performance, environmental tolerance, and nitrogen removal efficiency in wastewater. And the application of these Acinetobacter strains in diverse wastewater treatment settings might require careful optimization and real-time monitoring.

Sustainable Tandem Strategy for Recycling the Lithium-Ion Battery Cathode and Treating Waste by Cheap and Biocompatible Deep Eutectic Solvents

Dissolution of the cathode by deep eutectic solvents (DESs) is the key and green step to recycle spent lithium-ion batteries (LIBs); moreover, pollutant removal by adsorbents is the efficient route for environment protection. However, the couple of dissolving the LIB cathode and pollutant removal with high sustainability and low cost has not been reported up to now. Here, we for the first time use cheap and green DESs to dissolve LIBs for the preparation of magnetic adsorbents for wastewater treatment and engine oil removal. Results show that the removal efficiency of wastewater could reach as much as 94.5%. More importantly, the magnetic adsorbents after removing pollutants could be easily regenerated by a magnet. In addition to organic dye removal, the magnetic adsorbent could adsorb 576.75% engine oil. This work would provide a novel sustainable and cheap strategy for achieving spent LIB recycle and pollutant removal subsequently with high efficiency.

Treatment of phenolic wastewater by anaerobic fluidized bed microbial fuel cell filled with polyaniline–macroporous adsorption resin as multifunctional carrier

AbstractThe modified resin is used as a multifunctional biological carrier to treat phenolic wastewater (PW) in an anaerobic fluidized bed microbial fuel cell (AFB‐MFC). First, the modified resin was prepared, and the conductive polyaniline (PANI) was polymerized in situ on the surface and pores of the macroporous adsorption resin (MAR) to prepare the modified resin composite material (MAR/PANI). A series of modified resins with different mass ratios of resin and aniline were prepared. The modified resins were characterized by Fourier‐transform infrared spectroscopy, scanning electron microscopy (SEM), specific surface area, and pore structure analysis. Materials Studio (MS) software was used to study the internal interaction forces of PANI and MAR, and the molecular dynamics simulation method was used to analyze and calculate the cohesive energy density. The simulation results are qualitatively consistent with the experimental data. The sorption module in the MS software was used to study the adsorption behaviour of the modified resin to the organic components in the wastewater, and the adsorption mechanism was explained on the atomic scale. When the modified resin with m (MAR):m(An) = 1:0.6 was used in the AFB‐MFC, the chemical oxygen demand removal efficiency of wastewater was increased by 26.2%–88.90%, the voltage was increased by 98.46%–489.2 mV, and power density was increased by 303.28%–131.43 ± 0.17 mW/m2.

Towards efficient ciprofloxacin adsorption using magnetic hybrid nanoparticles prepared with κ-, ι-, and λ-carrageenan

The efficient removal of the antibiotic ciprofloxacin (CIP) from aqueous samples using magnetic nanosorbents prepared using three sulfated polysaccharides, κ-, ι- and λ-carrageenan and an alkoxysilane agent containing a reactive epoxide ring is described. The prepared nanosorbents were characterized in detail using FTIR spectroscopy, solid-state 29Si and 13C NMR spectroscopy and elemental microanalysis. The synthesis method was more effective for incorporating higher amounts of κ-carrageenan in the siliceous shells. Although being less sulfated, κ-carrageenan is cheaper than the other carrageenan tested. The CIP adsorption was a cooperative process, well described by the Dubinin–Radushkevich isotherm, with maximum adsorption capacities of 878, 969 and 865 mg/g for κ-, ι- and λ-carrageenan sorbents, respectively. Overall, the produced magnetic nanosorbents are among the best magnetic systems with high adsorptive efficiency for CIP. It is suggested that protonated CIP molecules are exchanged with ester sulfate counterions of carrageenan at the particles’ surface as the main pathway for CIP adsorption. The adsorption process was exothermic and entropically favorable for the three sorbents. However, at 298 K, the adsorption was spontaneous for κ-carrageenan-based sorbents and non-spontaneous for ι- and λ-carrageenan particles. The magnetic sorbents could be reused and maintained their ability towards CIP removal up to four cycles. The removal efficiency in wastewater was enhanced with the sorbent dose. Magnetic carrageenan nanosorbents were prepared using three carrageenan polysaccharides (κ-, ι-, and λ-carrageenan). The resulting magnetic particles removed the antibiotic ciprofloxacin efficiently from ultra-pure water and wastewater samples. Magnetic features enabled the fast magnetic separation of the nanosorbents from water.

Production and Characterization of a Novel Biosurfactant Molecule from Bacillus safensis YKS2 and Assessment of Its Efficiencies in Wastewater Treatment by a Directed Metagenomic Approach

Biosurfactant is a biodegradation accelerator that improves bioavailability and facilitates degradation by microorganisms. The study was meant to produce a novel biosurfactant molecule from Bacillussafensis YKS2. An efficient biosurfactant-producing strain, namely, Bacillus safensis YKS2, was selected using hemolytic activity, drop collapsing test, oil spreading test and blue agar plate methods in four oil-degrading strains isolated from a soil sample. Biosurfactant production in the optimization of bacteria culture conditions by RSM is a statistical grouping technique that is analyzed using the AVOVA approach to surface tention. In addition, the study was characterized by UV spectrophotometer FT-IR, HR-SEM, and GC-MS analyses to explain its structural and chemical details. Wastewater treatment was monitored for pH, EC, turbidity, alkalinity, chemical oxygen demand (COD), biochemical oxygen demand (BOD) and dissolved oxygen (DO) in order to justify the efficacy of the biosurfactant during wastewater treatment. The results of the UV spectrophotometer showed absorption at 530 nm, and the FT-IR analyzed carboxylic acids, alcohol and phenols groups, whichthe GC-MS analysis indicated were lipopeptide purified by hexadecanoic andtetradecanoic processes, respectively. The results show that the wastewater removal efficiency of 70% wasachieved within 24 h. In comparison, metagenomics was conducted during the treatment process to identify changes in the microbial load and diversity, which essentially indicatethe biosurfactant performance of the wastewater treatment process. The microbial load in the treated biosurfactant wastewater (84,374 sequences) was greatly decreased compared to untreated wastewater (139,568 sequences). It was concluded that B. safensis YKS2, producing a glycolipid form of biosurfactant, has possible benefits in the remediation of wastewater, and can be used for large-scale processing inbiosurfactant industries.

Chlorella vulgaris cultivation in simulated wastewater for the biomass production, nutrients removal and CO2 fixation simultaneously

Chlorella vulgaris (C. vulgaris) was promising microalgae to simultaneously achieve biomass production, carbon dioxide (CO2) fixation, nutrients removal and proteins production especially under different conditions of CO2 gas and wastewaters. Results presented that maximal specific growth rate of C. vulgaris was 0.21–0.35 d−1 and 0.33–0.43 d−1 at 0.038% and 10% CO2 respectively, and corresponding maximal CO2 fixation rate was attended with 4.51–14.26 and 56.26–85.72 mg CO2·L−1·d−1. C. vulgaris showed good wastewater removal efficiency of nitrogen and phosphorus at 10% CO2 with 96.12%–99.61% removal rates. Nitrogen fixation amount achieved 41.86 mg L−1 when the initial NH4Cl concentration was set at 60 mg L−1 at 10% CO2. Improved total protein (25.01–365.49 mg) and amino acids (24.56–196.44 mg) contents of C. vulgaris biomass was observed with the increasing of added CO2 and ammonium concentrations. Moreover, the developed kinetic function of C. vulgaris growth depends on both phosphorus quota and nitrogen quota with correlation coefficient (R2) ranged from 0.68 to 0.97. Computed maximal consumed nutrients concentrations (ΔCmax) based on Logistic function are positively related to initial NH4+-N concentrations, which indicated that adding ammonium could stimulate the utilization of both phosphorus and nitrogen.

Recycling of aquaculture wastewater and sediment for sustainable corn and water spinach production

This study develops a method to reuse aquaculture wastewater and sediment from a catfish pond in order to increase agricultural productivity and protect the environment. Material flow analysis (MFA) is a central concept of this study that involves collecting catfish pond wastewater (CPW) and reusing it to irrigate five water spinach (Ipomoea aquatic) ponds before discharging it into a river. Typically, catfish pond sediment (CPS) was collected and composted to produce organic fertilizer for cornfields. The results revealed that pollutant removal efficiency of wastewater from CPW (by using water spinach) were total organic carbon (TOC) = 38.78%, nitrogen (N) = 27.07%, phosphorous (P) = 58.42%, and potassium (K) = 28.64%. By adding 20 tons of CPS compost per hectare of the cornfield, the corn yield boosted 15% compared to the control field. In addition, the water spinach grew and developed well in the medium of wastewater from the fish pond. Altogether, the results illustrate that catfish pond wastewater and sediment can act as organic fertilizers for crops meanwhile reduce environmental pollution from its reuse.

Calcined electroplating sludge as a novel bifunctional material for removing Ni(II)-citrate in electroplating wastewater

Electroplating sludge as the hazardous waste produced from the electroplating wastewater treatment plants, is also precious resources of various transition metals. In this study, the novel calcined electroplating sludge (CES) was prepared via facile calcination and subsequently used as an effective bifunctional material for removing Ni(II)-citrate in electroplating wastewater. The CES displayed a high removal efficiency of Ni(II)-citrate in the CES/H2O2 system via oxidative degradation of complex compounds and adsorptive removal of Ni2+. The high removal efficiency could be ascribed to the excellent catalysis and adsorption ability of the CES. The Fe and Cu oxides in the CES were considered as reactive components for the activation of H2O2 to degrade the complex compound, while the oxygen-containing functional groups on the CES surfaces were responsible for the adsorption of Ni2+. Various parameters affecting Ni(II)-citrate in the electroplating wastewater removal efficiency were tested. With the addition of 50 mmol/L H2O2 and 1.5 g/L CES, 87% of the total nickel could be removed within 50 min when the total nickel concentration in the Ni(II)-citrate containing electroplating wastewater was 283 mg/L. This study provides a new method for the treatment of electroplating wastewater containing nickel-organic complexes by the electroplating sludge wastes. This technology can reduce the treatment cost of electroplating wastewater and achieve the concept of disposal waste with waste.

Degradation of p‐aminophenol wastewater using Ti‐Si‐Sn‐Sb/GAC particle electrodes in a three‐dimensional electrochemical oxidation reactor

AbstractIn this study, Ti‐Si‐Sn‐Sb/GAC particle electrodes were prepared by sol–gel method. The particle electrodes were characterized by SEM, XRD, EDX, and BET then used to carry out three‐dimensional (3D) electrocatalytic oxidation degradation on simulated refractory p‐aminophenol (PAP) wastewater. The effects of initial pH, cell voltage, aeration flow rate and initial PAP concentration on degradation experiments were investigated. Under the optimal conditions, the PAP and COD removal rates were 89.45% and 75.17% respectively. In addition, the possible degradation mechanism of PAP was further investigated by UV–Vis and HPLC. Finally, it was found that the Ti‐Si‐Sn‐Sb/GAC particle electrodes with high catalytic activity and excellent stability could significantly improve the PAP wastewater removal efficiency.

Unravelling the role of vegetation in the attenuation of contaminants of emerging concern from wetland systems: Preliminary results from column studies

Water pollution with contaminants of emerging concern (CECs) is widespread in water bodies due to the low effectiveness of industrial and urban wastewater treatment systems. In recent decades, the implementation of vegetation-based wastewater treatment systems such as wetlands has been observed to help solve this issue. However, there is a lack of knowledge regarding the removal percentage attributable to plants and how plants affect this removal improvement. In this study, we monitored planted (Phragmites australis) and unplanted sand columns to assess the effect of vegetation on the attenuation of 5 well-known CECs (benzotriazole, sulfamethoxazole, carbamazepine, bisphenol A, and diclofenac) and link it to the presence of different root exudates. The columns were operated in a continuous feeding mode for more than 6 months at 3 hydraulic loading rates (HLRs) (70, 140, and 280 mm d−1). We found that the presence of vegetation increased CEC attenuation from no effect to more than 200% compared to the unplanted columns. The highest effect was observed for carbamazepine (94–200%), followed by diclofenac (22–171%), benzotriazole (48–127%), and sulfamethoxazole (no effect to 43%), depending on the tested HLR. Furthermore, the greater CEC attenuation in planted columns was linked to the release of certain root exudates that may shape the root microbiome. We expect our assay to be a starting point for exploring the role of root exudates in enhancing CEC removal efficiency in wastewater.

Effect of micro-electrolytic fillers on the oil removal efficiency in wastewater

Aims to degrease the oily wastewater, the micro-electrolysis treatment with modified fillers was applied in this paper. The effect of micro-electrolytic filler on the oil removal was studied to determine the optimum proportion of carbon-iron, and corresponding preparation conditions. The result shows a relatively greater oil removal rate as 81.4% with safe effluent quality.

Treatment and Reuse of Black Water by Novel Energy-saving Shaft/Anaerobic /Anoxic/ Aerobic (S/A/A/O) System: A Novel Energy-saving Shaft/Anaerobic /Anoxic/ Aerobic (S/A/A/O) System for black water

In this study the novel integrated anaerobic/anoxic/aerobic (A/A/O) and shaft aeration process system which could enhance the nutrient removal efficiency of wastewater with a low carbon nitrogen ratio (C/N) was investigated. Several dissolved oxygen (DO) ratios (1.0-2.0, 2.0-3.0, 3.0-4.0 mg/L) were applied in order to obtain more knowledge on the biological nitrogen and phosphorus removal performances. The experiment was carried out on a lab-scale Shaft-Anaerobic-Anoxic-Aerobic (S/A/A/O) wastewater treatment system. The average removal efficiencies of the total organic carbon, total nitrogen and phosphorus were 84.0%, 82.0% and 93.7%, respectively. The result showed that the proposed system was promising for the treatment of wastewater with a low C/N ratio because that in this system nitrification and denitrification happened simultaneously. Besides, the system had an automatic return system and its floor area was small, which made it energy-saving.

TREATMENT EFFECTIVENESS EVALUATION OF WASTEWATER FROM INDUSTRIAL FRIED CHICKEN RE- PROCESSING PROCESSES BY ADVANCED OXIDATION PROCESSES

The experiment was conducted by using ozone and graphite electrodes to treat wastewater from industrial fried chicken re-processing peocesses with COD value ranges of 1600 - 2000 mgO2/L. A chamber of 20 liters was used in this study. The chamber height was 1 meter (the high response of 50-60 cm) in order to increase the diffusion of ozone into the wastewater. The study results showed that the amount of ozone needed for the reaction is 300 mg/h with COD removal efficiency of 40 % during reaction time of 45-60 minutes.The rate of BOD/COD increased within 1.55 - 1.80 times as compared with the BOD/COD rate of the initial wastewater. The experiments also showed that the COD removal efficiency of wastewater was not affected much by the pH value of the wastewater.

Research on the Treatment of Wastewater by Waste Ceramic Adsorption

The process of preparing porous ceramic with waste porcelain powder as aggregate was researched. The affect of assimilate time on cuprum removal efficiency in wastewater containing copper was investigated. The results show the water copper removal rate increased along with the augment of assimilate time, and the assimilate time is suitable for 35 min; XRD characterizations show the porous ceramic catalyst before and after calcination in active components of X ray diffraction peak position almost had no changes, and the diffraction intensity slightly changed with calcination and absorption, and diffraction peaks became sharper, and its crystallinity was improved. Baking leads to the growth of crystal particles, and the performance of porous ceramics is stable before and after adsorption.

Aerobic Biodegradation Characteristic of Different Water-Soluble Azo Dyes.

This study investigated the biodegradation performance and characteristics of Sudan I and Acid Orange 7 (AO7) to improve the biological dye removal efficiency in wastewater and optimize the treatment process. The dyes with different water-solubility and similar molecular structure were biologically treated under aerobic condition in parallel continuous-flow mixed stirred reactors. The biophase analysis using microscopic examination suggested that the removal process of the two azo dyes is different. Removal of Sudan I was through biosorption, since it easily assembled and adsorbed on the surface of zoogloea due to its insolubility, while AO7 was biodegraded incompletely and bioconverted, the AO7 molecule was decomposed to benzene series and inorganic ions, since it could reach the interior area of zoogloea due to the low oxidation-reduction potential conditions and corresponding anaerobic microorganisms. The transformation of NH3-N, SO42− together with the presence of tryptophan-like components confirm that AO7 can be decomposed to non-toxic products in an aerobic bioreactor. This study provides a theoretical basis for the use of biosorption or biodegradation mechanisms for the treatment of different azo dyes in wastewater.

The role of polychaeteNereis diversicolorin bioremediation of wastewater and its growth performance and fatty acid composition in an integrated culture system withHuso huso(Linnaeus, 1758)

This study was undertaken to evaluate the role of polychaete Nereis diversicolor in bioremediation of waste water and its growth performance and fatty acid composition in an integrated culture system with great sturgeon, Huso huso. Three treatments consisting of N. diversicolor fed with H. huso waste (FNW), N. diversicolor fed with fish feed waste (NW), and fish waste without the worm (FW) were considered at water temperature of 23°C for 8 weeks. The obtained results demonstrated that N. diversicolor in the flow-through system could grow via feeding with the fish waste water. The pure production and survival rate of harvested Nereis in NW treatment were significantly higher than those of FNW treatment (p < .05). However, no significant difference was observed in specific growth rate and weight gain between these two treatments (p > .05). The highest removal efficiency of waste water including total nitrogen (56%), total phosphorus (53%), NO2-N (91%), NH3-N (35%), PO4-P (47%), BOD5 (60%) were seen in FNW treatment. Also, the highest additional efficiency of NO3-N occurred in FW (37%) treatment. Certain fatty acids specifically 20:5 ω3 (eicosapentaenoic acid [EPA]) and 22:6 ω6 (docosahexaenoic acid [DHA]) were also abundant in Nereis, and analysis revealed some differences due to the diet. These results demonstrated that the promotion of growth by cultured Nereis can enhance the decomposition rate of organic matter in enriched sediment and minimize negative effects in fish farms. These results also suggest that the use of N. diversicolor is an excellent potential candidate for an integrated aquaculture and nutrient recycling including the removal of organic wastes.