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This study investigates the efficiency of a hybrid coagulation–flocculation process for the treatment of industrial wastewater from the steel industry. The novel method combines a natural coagulant, processed Rosehip Seed Powder (RSP), with a chemical coagulant, aluminum chloride (AlCl3), across varying concentrations and pH levels. The study simulated the pH 8 conditions of iron and steel industrial wastewater and examined the removal of heavy metals, total suspended solids (TSS), chemical oxygen demand (COD), and ammonia–nitrogen (NH3-N). At pH 8, the optimal coagulant dosage was determined to be 0.75:0.75 (g/g) of RSP/AlCl3 powder, resulting in high removal efficiencies across several parameters: 88.29% for COD, 91.85% for color, 99% for TSS, 93.11% for NH3-N, 94.3% for Mn, 98.5% for Fe, 96.7% for Zn, and 99.3% for Ni. The pH optimization demonstrated high removal efficiencies without pH adjudication. The removal of heavy metals at pH 8 demonstrated high efficiencies, with Mn, Fe, Zn, and Al achieving 99.00%, 90.6%, 95.73%, and 92.3%, respectively. These results suggest that no pH adjustment is required when using RSP/AlCl3 for the treatment of iron and steel industry wastewater through the coagulation method. [ABSTRACT FROM AUTHOR]

Commiphora gileadensis is a medicinal plant with a wide range of biological characteristics. Many medical diseases can be treated using the leaves of C. gileadensis, including bacterial infections, inflammatory illnesses, and wounds. As a result, the Soxhlet extraction method was used to extract the phenolic components and measure the recovery yields from C. gileadensis leaf. The impacts of the Soxhlet extraction parameters (extraction time 30–150 min, sample/solvent ratio 1:20–1:40 g/mL, and concentration of ethanol solvent 20–100% v/v) on the total flavonoid content (TFC), total phenolic content (TPC), and extraction yield were investigated using the one-factor-at-a-time (OFAT) technique. Fourier transform infrared spectroscopy (FTIR) and gas chromatography–mass spectroscopy (GC–MS) analyses have been employed to evaluate the extracts for the presence of various phytochemicals. According to the results, the C. gileadensis leafs ethanolic extract extracted via the Soxhlet process achieved the maximum yields at 90 min of extraction time, a feed/solvent ratio of 1:30 g/mL, and a 40% v/v ethanol concentration. These yields were: extraction yield = 23.20 ± 0.10% w/w, TPC = 59.93 ± 1.33 mg GAE/g d.w., and TFC = 19.65 ± 1.77 mg QE/g d.w.. Further, a total of 20 phenolic components with excellent antioxidant characteristics were found in the leaf extract of C. gileadensis extracted via the Soxhlet method. [ABSTRACT FROM AUTHOR]

Car wash wastewater (CWW) poses a significant environmental danger due to its high chemical oxygen demand (COD), heavy metals, and anionic surfactant complex composition, all of which can have an adverse effect on the environment. Even with the extensive research on CWW treatment, further study is necessary to improve our comprehension in this field. With an emphasis on CWW treatment processes and research trends, this study offers a comprehensive bibliometric analysis of 208 articles from the Scopus database. The analysis reveals that more than 55.77% of the research publications were released within the last five years, suggesting that there is increasing interest in the treatment of CWW. According to the data, the most important journal in this field is Desalination and Water Treatment. China and India were major research contributors. The main research directions in this area are properly indicated by the frequently used keywords "carwash wastewater", "electrocoagulation", "wastewater treatment", and "water reuse", according to an analysis of the keywords. Electrocoagulation, coagulation, and adsorption are common methods that are gaining popularity. In recent years, the most often researched CWW contaminants included those measured by COD and heavy metals. The results of this research offer an overview of recent developments. [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]

Healthcare facility wastewater considerably increases the levels of micropollutants in municipal wastewater. Considering this, the presence of contaminants of emerging concern in the environment has been highlighted as a global environmental problem. Electrochemical advanced oxidation (EAO) generate strong oxidants such as HO•, H2O2, and O3 - which can remove organic pollutants in water including pharmaceutical. This review presents the latest research findings concerning the mechanisms, influencing factors, and innovative approaches for treating wastewater generated by healthcare institutions. Electrochemical oxidation has proven a promising wastewater treatment technology, especially, for pharmaceutical-contaminated wastewater. EAO is widely regarded as a pioneering technique in the field of wastewater treatment because of its strong performance in the mineralization treatment for pharmaceuticals as well as the detoxification treatment of extremely biologically harmful organics. The use of EAO technology is of utmost importance in augmenting the efficiency of electrochemical systems in the decomposition of organic substances. Furthermore, it lays the groundwork for implementing these systems to treat wastewater derived from medical facilities and hospitals. Nevertheless, it is noteworthy that most experimental studies have focused on single-component wastewater that has been artificially prepared in laboratory settings. Wastewater from healthcare institutions often exhibits a complex and diverse composition, influenced by various factors. [ABSTRACT FROM AUTHOR]

The accumulation of aerobic microorganisms on the air-cathode in a single-chamber-microbial fuel cell can suppress the activity of the catalyst, and result in the reduction of the efficiency of the system. Therefore, a suitable mitigation measure is essential to control the growth of biofouling on the cathode. This study aims to investigate the effectiveness of chloramphenicol as an anti-biofouling agent on Pt-coated cathode. Two microbial fuel cells (MFCs) were used where the first (MFC-1) was a conventional Pt-coated air-cathode as a control, while the other one (MFC-2) with antibiotic mixed Pt-coated air-cathode. Results demonstrate that the maximum generated cell potential of 0.82 V in the control MFC-1 was reduced to 0.62 V after three months of operation due to biofouling development on the Pt-coated air-cathode. Besides, the control system achieved 95% chemical oxygen demand (COD) removal after 5 d of hydraulic retention time (HRT). However, using the newly developed cathode in MFC-2, the system achieved a maximum cell potential of 0.85 V with 95% of COD removal by 10 d HRT. The maximum columbic efficiency (CE) achieved in control MFC-1 and MFC-2 were 8 and 12.5%, respectively. The increment in CE was due to the absence of cathodic aerobic biofilm as well as the removal of COD was solely accomplished by the anodic biofilm. This result shows that the application of the antibiotic coating on the cathode can suppress the growth of cathodic biofouling without interfering with the other bio-electrochemical properties (COD removal, power recovery, pH change) of the system. [ABSTRACT FROM AUTHOR]

This study examines the use of date stone powder-based plant natural coagulant in the treatment of iron and steel industrial effluent. Coagulation process was conducted using different dosage from date stone powdered (0.2–10 g/L) and different pH values (5–10) using orbital shaker at 200 rpm. The treatment efficiency was evaluated by examine the removal for chemical oxygen demand (COD), total suspended solids (TSS), ammonia-nitrogen (NH3 –N), manganese (Mn), iron (Fe), zinc (Zn), aluminum (Al), and nickel (Ni). The maximal removal for COD, TSS, NH3 –N, Mn, Fe, Zn, Al, and Ni were 59.4%, 99%, 92.1%, 87.1%, 97.7%, 94.8%, 65.8%, and 80.3%, respectively. Date stone powder has enormous promise as a plant-based natural coagulant for industrial effluent wastewater treatment and might be used to treat effluent from the iron and steel industries. [ABSTRACT FROM AUTHOR]

Various chemical coagulants have previously been used for wastewater treatment with substantial efficacy in eliminating heavy metals and other criteria. However, their economic effectiveness and the remnant of harmful chemical precipitates that pose hazards to human health and the environment. As a result, utilizing plant-based natural coagulants is seen as an alternative non-toxic, biodegradable, and ecologically beneficial strategy. This study aims to investigate the performance of pinecone seed powder as a natural coagulant in iron and steel factory wastewater treatment, as well as to optimize the operating parameters to determine the feasibility of employing pinecone seed powder in wastewater treatment. Using 0.6 g/200 mL pinecone as a controlling factor, pH, and settling time, the response surface methodology, a statistical experimental design was utilized to increase the chemical oxygen demand (COD), ammoniacal nitrogen (NH3–N), and heavy metals removal efficiency. COD, NH3–N, Fe, Mn, Ai, Cu, and Ni removal efficiencies at pH 8 were 76%, 44%, 88%, 93%, 87%, 50%, and 92%, respectively. Except for Fe (0.0170), Mn (0.0021), and Cu (0.001), the quadratic models for the parameters specified were determined to be significant with a low probability. [ABSTRACT FROM AUTHOR]

The use of olive seed powder as a plant-based natural coagulant in treating iron and steel factory wastewater was studied. The concentrations of chemical oxygen demand (COD), total suspended solids (TSS), ammonia-nitrogen (NH3 –N), manganese (Mn), iron (Fe), zinc (Zn), aluminum (Al), and nickel (Ni) in effluent wastewater were investigated. Coagulation experiments on the effects of iron and steel factory wastewater, pH, and olive seed powder dosage on coagulation efficacy were conducted using an orbital shaker and a flocculation device. The maximum removal percentages of COD, TSS, NH3 –N, Mn, Fe, Zn, Al, and Ni by olive seeds powder were 86.3%, 99%, 72.4%, 80.9%, 91.5%, 92.6%, 73.7%, and 84.3% for effluent at natural pH 8 using a 5 g/L dosage, respectively. The Fourier-transform infrared spectroscopy study showed the presence of several functional groups involved in the coagulation process. It is possible to argue that olive seed powder has enormous potential as a plant-based natural coagulant for wastewater treatment and that it might be used to treat wastewater from iron and steel factories. [ABSTRACT FROM AUTHOR]

Solar energy has recently become a viable option for desalinating seawater, primarily in arid regions. However, increasing the productivity of solar still by integrating experimental base and modelling methods is still subject to prediction errors; therefore, the main objective of this research is to postulate and test boosting algorithms for predicting the efficiency and productivity of the system. Five boosting regressors were deployed and evaluated: categorical boosting, adaptive boosting, extreme gradient boosting, gradient boosting machine, and gradient boosting machine (LightGBM). The proposed regressors are implemented based on the system’s actual recorded dataset (consisting of 720 observations). The dataset consists of input variables, which are the wind speed (V), cloud cover, humidity, ambient temperature (T), solar radiation (SR), (Tio), (Tw), (Tv), and (Tt). Also, the output variable is represented by the productivity of the system. The dataset was separated into training (70%) and testing (30%) sets. In order to decrease regressors errors, hyperparameter optimization was employed. GradientBoosting approach provided the best prediction, with 95% R2 accuracy and 39.57 root mean square error (RMSE) error. The LightGBM technique achieved 94% R2 accuracy and 40.07 RMSE error in the testing dataset. The results reveal that GradientBoosting outperforms the cascaded forward neural network in predicting system productivity (CFNN). [ABSTRACT FROM AUTHOR]

Two coagulants (Al2(SO4)3 and FeSO4) were investigated for their performance in treating raw and anaerobic effluents from a palm oil mill. The treatment efficiencies for both palm oil mill effluents (POMEs) were assessed based on chemical oxygen demand (COD) removal. Different dosages of Al2(SO4)3 and FeSO4 were investigated in terms of COD removal in raw and anaerobic effluents under different pH levels. The results show that FeSO4 performed better than Al2(SO4)3 in removing COD from both effluents. The maximum COD removal efficiency (94%) was achieved when both effluents were treated with 0.4 g of FeSO4 at pH 3, while the maximum COD removal achieved by Al2(SO4)3 was 70% using 0.4 g at pH 7. Using these optimal operational conditions, the removal of 11 parameters, namely COD, color, total suspended solids (TSS), electrical conductivity, biochemical oxygen demand (BOD), pH, NH3-N, Cu+2, Fe+2, Zn+2, and Pb were measured and assessed. The results were analyzed statistically using factor analysis (FA) and cluster analysis (CA) to identify the main factors responsible for the differences in the parameters and to display the similarity and dissimilarity between the selected parameters among the different POME sources. The FA method produced four factors responsible for more than 99% of the differences in data. The first factor covered COD, color, TSS, and BOD and was responsible for explaining 36% of the differences, whereas the second factor was responsible for explaining 34% of the differences, including NH3-N, Cu+2, Fe+2, and Zn+2. The percentage variance explained by the third and fourth factors was 16% and 14%, respectively. The CA method produced three different groups (clusters). It was found that raw and anaerobic POMEs treated with Al+3 and raw POMEs treated with Fe+2 were close to each other, representing the second cluster, while the raw treatment represented the first cluster. The last cluster represents the anaerobic effluent before and after coagulation using Fe2SO4. The results reveal that Fe2SO4 is an efficient method for removing organic and heavy metal content from POME. The study provides essential data and knowledge that can be used to evaluate and manage POME treatment. [ABSTRACT FROM AUTHOR]

Microplastic is an emerging pollutant causing trouble worldwide due to its extensive distribution and potential hazards to the ecological system. Some fundamental questions about microplastics, such as their presence, source, and possible hazards, remain unanswered. These issues develop because of a lack of systematic and comprehensive microplastic analysis. As a result, we thoroughly evaluated current knowledge on microplastics, including detection, characterization, occurrence, source, and potential harm. Microplastics are found in seawater, soil, wetlands, and air matrices worldwide based on findings. Visual classification, which can be enhanced by combining it with additional tools, is one of the most used methods for identifying microplastics. As soon as is practicable, microplastics analytical methods ought to be standardized. New techniques for analyzing nano-plastics are urgently needed in the meantime. Numerous studies have shown that microplastics’ impacts on people and soil are significantly influenced by their size, shape, and surface physicochemical characteristics. Finally, this study suggests areas for future research based on the knowledge gaps in the area of microplastics. [ABSTRACT FROM AUTHOR]

This study aims to investigate the performance plant-based natural coagulant from rosehip seed powder in the treatment of iron and steel factory wastewater. The concentrations of COD, total suspended solids (TSS), ammonia-nitrogen (NH3–N), manganese (Mn), iron (Fe), zinc (Zn), aluminum (Al), and nickel (Ni) in effluent wastewater were examined. Coagulation investigations were carried out using an orbital shaker and a flocculation apparatus to investigate the effects of iron and steel factory effluent, pH, and rosehip seeds powder dosage on coagulation efficacy. The rosehip powder removes a large amount of COD, TSS, NH3–N, Mn, Fe, Zn, Al, and Ni from effluent at pH 8 with percentages of 86.1%, 99%, 79%, 86%, 91.7%, 90.6%, 73.7%, and 100%, respectively, at 1 g/L. The effects of pH ranges ranging from (5–10) reveal that the wastewater sample’s natural pH (8) demonstrates the maximum practicable removal effectiveness. FTIR analysis revealed the presence of numerous functional groups involved in the coagulation process. One may argue that rosehip seed powder holds great potential as a natural plant-based coagulant for water treatment and could be used to treat effluent from iron and steel factories. [ABSTRACT FROM AUTHOR]

Utilization of pinecone powder as a plant-based natural coagulant for the treatment of iron and steel factory effluent was examined. The concentrations of chemical oxygen demand (COD), total suspended solids (TSS), ammonia-nitrogen (NH3 –N), manganese (Mn), iron (Fe), zinc (Zn), aluminum (Al), and nickel (Ni) in effluent wastewater were investigated. Results showed that the maximal removal of COD, TSS, NH3 –N, Mn, Fe, Zn, Al, and Ni using pinecone powder were 83.3%, 99%, 83.9%, 86.8%, 93.7%, 89.7%, 73.7%, and 86.7%, respectively for effluent at natural pH 8 using a dosage of 3 g/L. The Fourier-transform infrared spectroscopy result showed the existence of various functional groups involved in the coagulation process. Overall, this study shows that pinecone powder has enormous promise as a natural coagulant for water treatment and it could be utilized to treat effluent from iron and steel plants. [ABSTRACT FROM AUTHOR]

Thermal remediation technologies are fast and effective tools for the remediation of contaminated soils and sediments. Nevertheless, the high energy consumption and the effect of high temperature on the soil properties may hinder the wide applications of thermal remediation methods. This review highlights the recent studies focused on thermal remediation. Eight types of thermal remediation processes are discussed, including incineration, thermal desorption, stream enhanced extraction, electrical resistance heating, microwave heating, smoldering, vitrification, and pyrolysis. In addition, the combination of thermal remediation with other remediation technologies is presented. Finally, thermal remediation sustainability is evaluated in terms of energy efficiency and their impact on soil properties. The developments of the past decade show that thermal-based technologies are quite effective in terms of contaminant removal but that these technologies are associated with high energy use and costs and can has an adverse impact on soil properties. Nonetheless, it is anticipated that continued research on thermally based technologies can increase their sustainability and expand their applications. Low temperature thermal desorption is a promising remediation technology in terms of land use and energy cost as it has no adverse effect on soil function after treatment and low temperature is required. Overall, selecting the sustainable remediation technology depends on the contaminant properties, soil properties and predicted risk level. [ABSTRACT FROM AUTHOR]

Nanoscale zero-valent iron (nZVI) has been extensively investigated for the remediation of soil, wastewater, and groundwater contaminated with heavy metals. This paper presents a collective review of nZVI synthesis, nZVI interaction mechanisms with heavy metals, factors affecting nZVI reactivity, recent applications of nZVI for heavy metals removal, and the environmental concerns of nZVI application for soil microorganisms and plants. Modified nZVI, spatially biochar supported nZVI (BC@nZVI) and sulfidation nanoscale zero-valent iron (S-nZVI) showed high heavy metals removal efficiency and more stable performance compared to nZVI alone. The removal of heavy metals by nZVI is as a synergistic process where adsorption, oxidation/reduction and precipitation occur simultaneously or in series. pH and organic matter are the main factors that significantly affect nZVI reactivity. Toxic effects of nZVI are observed for the soil microorganisms as the direct contact may cause a decrease in cell viability and membrane damage. A low concentration of nZVI promotes the growth of plant whereas high concentration decreases root length. It is observed that, further research is needed to enhance nZVI recovery techniques, evaluate the effectiveness of novel modified nZVI and their effects on the environment, and the full-scale application of nZVI. [ABSTRACT FROM AUTHOR]

Landfill remains as the most common municipal waste disposal method in the world. However, the production of leachate associate with landfill persists as a major drawback, which bring harmful effect to the environment. Persulfate oxidation is recently used for stabilized leachate treatment. Persulfate alone is still limited for leachate oxidation and an activation method is required to improve its performance. Accordingly, this study aims to investigate and compare the performance of persulfate subjected to thermal activation in treating stabilized leachate. Different experimental operational factors were considered and evaluated such as, S2 O8 2–/chemical oxygen demand (COD) ratio, temperature, and reaction time. Experiments were designed and optimized by using response surface methodology, and results were analysed by using analysis of variance. The removal efficiencies for COD and colour using inactivation persulfate were reported only at 14% and 29%, respectively. However, the efficiencies were improved to 93.39% and 94.00% for COD and colour after thermal activation of persulfate under an optimum condition of 10 S2 O8 2–/COD ratio, 80°C and 120 min. The maximum efficiency was achieved at the treatment cost of RM0.66 per litre of leachate. [ABSTRACT FROM AUTHOR]

The process of coagulation-flocculation using Dioscorea hispida starch as a natural coagulant was investigated for the purification of textile effluent from several dyeing and finishing mills. The major parameters tested were COD, turbidity, and color. Prior to conducting the experiments, the general physical characteristics of Dioscorea hispida starch were investigated. The optimal conditions, pH and coagulant dosage were assessed using a jar test. The results demonstrated that the Dioscorea hispida starch yield was 15.38% of Dioscorea hispida dry weight. Pulverizing of Dioscorea hispida mass also resulted in approximately 10-15% of impurities in the final product. The optimal pH of 7 resulted in maximum COD, turbidity and color reductions of 28%, 94% and 64% respectively. The optimum dosage of Dioscorea hispida starch of 2500 mg/L resulted in a maximum reduction of 22%, 93%, 63%, of COD, turbidity, and color, respectively. Overall, this study confirmed that the utilization of Dioscorea hispida starch as a natural coagulant offers a relatively good removal efficiency in textile wastewater treatment. [ABSTRACT FROM AUTHOR]

This study examined the applicability of oil palm frond-activated carbon (OPF-AC) as adsorbent in the treatment of landfill leachate. OPF-AC was prepared by mixing granular OPF with an aqueous solution composed of distilled water and zinc chloride (ZnCl2) at different ratios. Batch experiment studies were carried out to investigate the optimum OPF-AC dosage as well as the optimum shaking time. The optimum condition was achieved at 1.2 g of OPF-AC dosage and 50 minutes of shaking time. The highest removals of COD, color and Fe (77%, 75% and 69%, respectively) were obtained at the optimum condition. Meanwhile, the adsorption capacities were 146.93 mg/g (COD), 56.43 mg/g (color) and 0.11 mg/g (Fe). The increase in adsorbent dosage also resulted in a larger free surface area and exchangeable binding sites. However, the unsaturation of adsorption sites during the adsorption process resulted in a slight drop in removal efficiency of COD, color, and Fe. Furthermore, due to the aggregation and overcrowding of adsorbent particles, the use of a greater amount of adsorbent dosage imposed particle interactions. [ABSTRACT FROM AUTHOR]