Operational Parameters Research Articles

Deoxygenation Pathways for Sustainable Aviation Fuel from Used Cooking Oil: A Review on Catalyst and Operating Parameters

Deoxygenation Pathways for Sustainable Aviation Fuel from Used Cooking Oil: A Review on Catalyst and Operating Parameters

Optimizing the Extraction of Polyphenols from the Bark of Terminalia arjuna and an In-silico Investigation on its Activity in Colorectal Cancer.

The interconnection between different fields of research has gained interest due to its cutting-edge perspectives in solving scientific problems. Terminalia arjuna is indigenously used in India for curing several diseases, and its pharmacological activities are being revisited in recent drug-repurposing research. Efficient ultrasound-assisted extraction of phytochemicals from the bark of Terminalia arjuna is highlighted in this study. Following the optimization of the extraction process, the crude hydroethanolic extract is subjected to phytochemical profiling and an in-silico investigation of its anti-cancer properties. A three-level four-factor Box-Behnken design is exploited to optimize four operational parameters, namely extraction time, ultrasonic power, ethanol concentration (as the extracting solvent) and solute (in g): solvent (in mL) ratio. At the optimum parametric condition, the crude extract is obtained, and its GC-MS analysis is carried out. An analysis of network pharmacology (by constructing and visualizing biological networks using Cytoscape) combined with molecular docking reveals the potential antineoplastic targets of the crude extract. The ANOVA table exhibits the significance, adequacy and reliability of the proposed second-order polynomial model with the R² value of 0.917 and adjusted R² of 0.865. Experimental results portray the significant antioxidant potential of the prepared extract in its crude form. The GC-MS analysis of the crude extract predicts the extracted phytochemicals, while the constructed biological networks highlight its multi-targeted activity in colorectal cancer. The study identifies three phytochemicals viz. luteolin, β-sitosterol and arjunic acid as potent anti-cancer agents and can be extended with in-vitro and in-vivo experiments to validate the in-silico results, thus establishing lead phytochemicals in multi-targeted colorectal cancer therapies.

Safety and security of household water purifiers against pathogenic microbial contamination and bio-risk evaluation of their microbial community structures

Household water filters, particularly point-of-use systems, are crucial to ensure safe drinking water consumption by eliminating microbial contaminants. This study evaluated the efficacy of three types of water purifiers (ultrafiltration [UF], nanofiltration [NF], and reverse osmosis [RO]) against microbial contamination. In our experiments, Escherichia coli and bacteriophage MS2 were used as two microbial indicators in daily household settings to track the spatial and temporal profiles of their behavior from the filter inlets to in-UF, NF, and RO water purifiers, and then to effluents. The results showed that both NF and RO water purifiers removed 100 % of the indicator organisms. The UF water purifier achieved 100 % removal of E. coli, but the removal of MS2 phage was poor. The presence of coexisting ions and natural organic matter in tap water can significantly affect the behavior of MS2 phages during the water treatment process. Their presence reduces the charge repulsion effect of the UF membrane on the MS2 phage as well as promotes the migration of the MS2 phage on the post-activated carbon cartridge that was placed in the last unit of the water purifier system, which could increase the pathogen transmission risks in drinking water supplies. The bacterial community structures of the cartridge materials and cartridge effluents from each unit were analyzed by 16S rRNA gene sequencing, which revealed distinct microbial profiles of the different purifiers. Environmental conditions such as pH, nutrient availability, materials, and operational parameters can affect the composition of bacterial communities. Scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDS) was used to examine the surface morphology of the membranes after they were exposed to water contaminants, which demonstrated that the inherent differences in the membrane structure influenced the retention of pollutants and microorganisms on the surfaces. In summary, this study demonstrates that both NF and RO water purifiers can significantly reduce the presence of various enteric and opportunistic pathogenic bacteria in drinking water, leading to safer potable water, whereas UF water purifiers may have certain risks owing to their UF membranes and post-activated carbon. In addition, secondary microbial contamination may be introduced by the post-activated carbon units of water purifiers, especially after long-term usage. Therefore, we concluded that addressing the secondary microbial pollution caused by post-activated carbon after prolonged use and long-term shutdown is essential for maintaining the safety and quality of drinking water.

Effective degradation of ciprofloxacin from aqueous solutions using heterogeneous electro-Fenton coupled with Fe@Fe2O3 core-shell nanoparticle

In the current research, a Ti/RuO2 anode and Fe@Fe2O3 catalyst were synthesized for electro-Fenton (EF) removal of ciprofloxacin (CIP). The results of the ANOVA from response surface methodology (RSM) indicated a significant relationship between experimental and predicted values. 100% CIP and 45% total organic carbon (TOC) removal were predicted at pH of 8.83, time of 14.80min, current density of 19.19mA/cm2, pollutant concentration of 15.13mg/L, and catalyst dosage of 199.03mg/L. Among the operational parameters, current density (F value = 191.90) and catalyst dosage (F value= 5.79) had the greatest and least effect on the CIP removal rate, respectively. The stability tests revealed excellent reusability of electrodes for long-term decomposition of CIP. The BOD5/TOC > 0.6 in the treated solution confirmed acceptable performance of the heterogeneous EF process in CIP degradation. A 25% growth inhibition rate of plant stems in the treated solution demonstrated the low toxicity and biodegradability of the effluent. The efficiency of the heterogeneous EF process for CIP removal in water matrices ranged from 43.65% to 100%. By evaluating the parameters, mineralization, production of different radicals, and energy consumption, the heterogeneous EF process can be considered for the effective decomposition of CIP from aqueous environments.

Enhanced drug release through nitrendipine/hydroxypropyl methylcellulose solid dispersion via supercritical antisolvent technique

The poor water solubility of nitrendipine (NT) results in low oral bioavailability, which hinders its practical application. Hydroxypropyl methylcellulose (HPMC) is a prominent drug carrier that has been applied in the biomedical field due to its significant characteristics, such as large surface area, biocompatibility and biodegradability. In this study, an efficient drug delivery system based on the preparation of NT/HPMC solid dispersion using supercritical antisolvent (SAS) technology was proposed. The effect of different operating parameters such as solvent, host guest ratio, concentration, temperature, and pressure on NT/HPMC was optimized to obtain dispersed particles with maximum solubility. The formed solid dispersion presents non-static spherical particles with a high surface area and small particle size. Importantly, in vitro drug release studies have demonstrated that the dissolution and solubility of NT in solid dispersion are significantly enhanced compared to pure drugs. In vitro bioactivity experiments showed that the NT/HPMC solid dispersion has good biocompatibility and antibacterial performance. Thus, this study indicates that solid dispersion prepared using SAS technology are considered a promising drug delivery system.

Optimization of co-injecting CH4 with CO2 to enhanced oil recovery and carbon storage: A machine-learning based case study on H59 block of Jilin Oilfield, China

During CO2-EOR implementation, CH4 in the reproduced CO2-rich mixture are included in the recycle injection gas. However, improper injection gas composition and operation parameters can reduce the flooding performance.In this study, a machine-learning assisted framework combining Convolutional Neural Networks-Gate Recurrent Unit (CNN-GRU) and Non-dominated Sorting Genetic Algorithm II (NSGA-II) was proposed to obtain the optimal parameters for simultaneous maximum oil production, carbon storage efficiency, and net present value. A case study from the CO2-EOR project in the H59 block of Jilin oilfield, China, was carried out. Base cases were established to evaluate the effects of reinjection CH4 on flooding performance.Results show that the built CNN-GRU model has high prediction accuracy and computational efficiency, and thus can be used as an alternative tool to the reservoir simulator. The proposed framework can find the optimum parameters to improve oil recovery, carbon storage and net present value. The co-injection of CH4 and CO2 improves oil production, and carbon storage performance, but reduces the net present value. This work provides engineers with multiple strategies for decision-making to simultaneously promote flooding performance with CH4 being a co-injectant in CO2-EOR projects.

An upgrade of the radial probes for HIRFL-SFC

SFC (Sector Focusing Cyclotron) is essential to the Heavy Ion Research Facility in Lanzhou (HIRFL). Its beam extraction efficiency is directly related to the overall operational efficiency of the accelerator. The original radial probes of the SFC, due to its outdated equipment, no longer meet the requirements for beam tuning in terms of mechanical precision, vacuum level, and local noise. Three new sets of radial probes have been developed in phases. These devices were installed at the accelerator site during annual maintenance, providing axial and radial beam distribution during acceleration. Since 2020, the system has been operating without any failures, providing corresponding beam parameters for the accelerator's operation and ensuring the normal functioning of the accelerator.

Evaluating the effectiveness of the modified multi-scale multi-physics coupled model for solid oxide fuel cells: A comparative analysis

A multi-scale multi-physics coupling numerical model serves as an effective tool to study the performance and improve the efficiency of solid oxide fuel cells (SOFCs) and provides the theory and data support for optimizing SOFC structure and operational strategy. To improve the accuracy and reliability of the model, this work established a modified simulation model that considers the effect of operational, structural, and physical parameters of SOFCs. First, the electrochemical kinetics equation, multi-component diffusion lattice Boltzmann (LB) model, and heat transfer LB model are modified by incorporating the reaction gas molar fraction, gas mixture concentration, temperature, and other parameters. Second, a regional hierarchical modeling strategy is proposed, and the multi-scale coupling model is modified by coupling mass and heat transfer. Third, considering the effect of carbon monoxide molar fraction, temperature difference, concentration change and porosity on electrochemical, mass, and heat transfer processes, the effectiveness of modification model is analyzed and validated. Results demonstrate that the modified model considerably improves the numerical simulation to handle the complex operational conditions of SOFCs. The modified model's predictions show better accuracy compared with experimental data, while maintaining consistency with the trends predicted by the original numerical models.

Numerical investigation of dynamic gas–liquid separator by population balance model

Dynamic gas–liquid separator (DGLS) can efficiently separate gas and liquid phases and are widely used in aerospace, chemical, and petroleum engineering. The energy loss and separation efficiency within the DGLS are studied through the combination of numerical simulations and experiments. Three-dimensional transient Reynolds-Averaged Navier–Stokes equations were solved to analyze the fluid dynamics within the DGLS. The bubble aggregation and breakup in oil were simulated by using the population balance model. Experimental data were meticulously compared with numerical results to validate the accuracy and reliability of the numerical methods. The findings revealed a direct correlation between the inlet flow rate and various performance metrics of the DGLS. Specifically, as the inlet flow rate increased, the energy loss within the DGLS escalated, resulting in higher power consumption. The degassing rate of the DGLS exhibited a decreasing trend with increasing inlet flow rate, while the de-oiling rate showed an inverse relationship. The optimal performance of the separator was observed at an inlet flow rate of 140 m3·d−1, with ηg* and ηl* reaching 0.94 and 0.99, respectively. The relationship between the Qo and the η* and Po was fitted by a second-order polynomial. Moreover, the rotational speed of the DGLS demonstrated a positive correlation with energy consumption, accompanied by an increase in power output. However, the separation efficiency of the DGLS exhibited a non-linear relationship with rotational speed, peaking at a specific value before marginally declining. The optimization of degassing and dewatering rates occurred at a rotational speed of 2500 r·min−1. These findings underscore the importance of carefully adjusting operational parameters to achieve optimal performance and energy efficiency within DGLS.

Synergistic Management of Nitrogen Contamination in Overflow Wastewater and Algal Proliferation in Lake Receiving Wastewater Based on Electrochemical Oxidation Process

Urban lake eutrophication, largely driven by overflow wastewater, plays a pivotal role in precipitating algal proliferation due to heightened nitrogen levels in aquatic ecosystem. In addressing this question, this study investigated the chloride-mediated electrochemical oxidation system as a promising solution for controlling nitrogen contamination in overflow wastewater and inhibiting algal proliferation in wastewater-receiving urban lakes, and also evaluated the influence of essential operational parameters on the performance of system. The results indicated that, under the environmental conditions set by this experiment, the removal efficiency ranges of ammonia nitrogen and total nitrogen were 14.91% - 100% and 13.98% - 99.62%, respectively; meanwhile, the maximum algae inhibition rate could reach 100% at a capacity ratio of 0.01. Response Surface Method analysis highlighted current density as the preeminent factor in nitrogen removal and algae inhibition, surpassing the influence of initial chloride ion and nitrogen concentrations within the system. Notably, an excessive current density could inadvertently lead to the nitrate nitrogen accumulation (up to 29%), thereby diminishing the total nitrogen removal efficiency, particularly in low nitrogen-concentrated overflow wastewater scenarios. With respect to algae inhibition, a direct correlation was identified between higher residual total chlorine concentrations in the receiving lake and increased algae inhibition rates (R = 0.90, P < 0.05), and the residual total chlorine was found to exert pronounced inhibition on cyanobacteria compared to other algal forms. However, caution was advised regarding potential algal growth stimulation if the initial received total chlorine concentration in the urban lake receiving wastewater below 0.5mg/L. These findings not only affirm the feasibility of this synergistic approach but also elucidate critical aspects for process optimization and control.

Alarm management approach for supervision of Green Hydrogen Plants

Amid the increasing significance of renewable energy sources, Green Hydrogen Plants (GHPs) have emerged as pivotal contributors to sustainable energy solutions. However, efficient and reliable alarm management in such complex systems remains a significant challenge. This paper presents a novel methodology called V-nets-based alarm management (VBAM), designed to improve supervision by addressing the intricacies of discrete event management in industrial applications such as GHPs. VBAM offers a powerful formalism that integrates visual modeling and temporal patterns, enabling the precise detection and handling of alarms. The proposed methodology is applied to a case study in a GHP, where critical operational parameters are continuously monitored. By analyzing discrete events and their temporal patterns, V-nets facilitate early fault detection, minimize false positives, and optimize alarm response. The theoretical application of VBAM demonstrates its efficacy in improving system safety, reducing downtime, and enhancing overall operational efficiency within GHPs. The contributions of this work to the state of the art include the development of a comprehensive VBAM methodology tailored to GHPs, as well as the theoretical and practical demonstration of its potential impact on alarm management within GHP operations. The outcomes from the experiments showcase the adaptability and effectiveness of VBAM in addressing the complexities of alarm management in GHPs, thereby contributing to enhanced safety, efficiency, and resilience in the operation of GHPs.

Examining the factors that impact the formation of barite scale in water injection operations: experimental study and quantification of scale formation

Barium sulfate (BaSO4) scale formation in oilfield operations is a significant problem that leads to severe operational challenges, including reduced production efficiency and increased maintenance costs. Understanding the factors that influence BaSO4 scale formation, such as injection rate and temperature, is crucial for developing effective mitigation strategies. In this study, we systematically investigated the effects of injection rate and temperature on BaSO4 scale formation using a series of controlled laboratory experiments. The injection rates varied between 1 and 5 mL/min and temperatures between 25 and 75 °C, simulating realistic field conditions. Our findings indicate that higher injection rates and elevated temperatures significantly increase the amount of BaSO4 scale formed. Specifically, the scale formation increased from 15.2 mg/L at 1 mL/min and 25 °C to 22.3 mg/L at 5 mL/min and the same temperature. Similarly, at a constant injection rate of 3 mL/min, the scale formation increased from 18.1 mg/L at 25 °C to 26.5 mg/L at 75 °C. The study employed Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) to analyze the crystal morphology and structure of the formed scales. SEM images revealed a transition from dendritic structures at lower temperatures and slower injection rates to spherical crystals at higher temperatures and faster injection rates. XRD patterns indicated variations in crystallinity and phase purity corresponding to the experimental conditions. Our results align with previous studies that report increased nucleation rates and reduced solubility of BaSO4 at higher temperatures and injection rates. These findings highlight the critical role of controlling operational parameters to mitigate scale formation in oil and gas operations. By optimizing injection rates and temperatures, it is possible to reduce scale deposition, thereby improving production efficiency and reducing maintenance costs. This study provides valuable insights for the development of scale management strategies and underscores the importance of a comprehensive understanding of the physicochemical factors affecting BaSO4 scale formation.

Energy-economic-environmental analysis of bifacial photovoltaic thermal (BPVT) solar air collector with jet impingement

Jet impingement cooling enhances photovoltaic (PV) system efficiency by using high-speed fluid jets to reduce panel temperatures, improving performance and longevity. The effectiveness depends on factors like fluid flow rate, nozzle placement, and distance from the panel. While it boosts energy output, it may increase energy use for fluid circulation and add complexity to the system. This research explores a groundbreaking approach to enhancing the efficiency of bifacial photovoltaic thermal (BPVT) systems by integrating jet impingement technology. A novel design featuring a jet plate reflector is introduced, offering the dual benefit of cooling the PV panels while simultaneously reflecting light to optimize energy capture. The study comprehensively analyses the system’s performance, including energy output and a detailed techno-economic and environmental-economic evaluation. The modelling in this study was validated and reasonably consistent with experimental results. The system's output air temperature and thermal efficiency are 302.07-318.75 K and 33.83-62.28%, respectively. The temperature and electrical efficiency range for PV systems are 304.39-339.54 K and 9.39-11.22%. Reduced mass flow rate and increased solar irradiation are the most economically advantageous operating parameters for the proposed system, resulting in lower annual pumping costs and more significant annual energy gains for the system. CBR variations range from 0.1363 to 9.3445, with an average of 2. Additionally, by using BPVT with jet impingement to generate electricity rather than fossil fuels, it is possible to reduce annual carbon dioxide emissions by approximately 1.61 tons and save RM93.51 annually. In general, the proposed method should be used to minimize environmental pollution.

Catalytic performance of FeCo2O4 spinel cobaltite for degradation of ethylparaben in a peroxymonosulfate activation process: Response surface optimization, reaction kinetics and cost estimation

The presence of cosmetics and personal care products in water resources has become an increasing concern for environment due to their toxicity and persistence in aquatic medium. Peroxymonosulfate mediated advanced oxidation methods have a great potential for the efficient removal of complex organic compounds due to the generation of highly reactive radicals with high oxidation ability. Iron cobaltite, FeCo2O4 catalyst was used as a peroxymonosulfate (PMS) activator for the degradation of ethylparaben which was selected as a model personal care product ingredient. Paraben degradation was modelled and the optimum operating parameters were determined by using Box-Behnken design. The ethylparaben degradation efficiency was calculated as 94.6% under the optimized conditions which were determined as 0.9 g/L FeCo2O4 loading, pH 6.15, and 0.26 g/L PMS dosage. The ethylparaben degradation reaction followed second-order reaction kinetics. The activation energy was evaluated as 40.1 kJ/mol. Quenching radical tests showed that the dominant reactive species were hydroxyl radicals. Toxicity of the treated samples in terms of L. sativum growth inhibition was evaluated as 1.5%. The total cost of the treatment including the operating and the amortization costs was calculated as 0.91 €/L.

Evaluation, optimization study, and life cycle assessment of novel eco-friendly PVA-based nanocomposite hydrogel adsorbents for methylene blue and paracetamol removal

In this study, an eco-friendly and novel hydrogel based on a crosslinked polyvinyl alcohol (PVA), iota carrageenan (IC) and polyvinylpyrrolidone (PVP) scaffold, containing a large amount (10-50wt. %) of nanoscale palm fronds (NPF) as additives, for water purification was demonstrated. A life cycle assessment (LCA) findings on NPF as biomass waste incorporated into PVA_PVP_IC polymer matrix was presented, and the results highlight the necessity of focused actions to reduce environmental impact and support the palm waste utilization in a sustainable manner. The multicomponent nanocomposite hydrogels were examined as adsorbents in a system work in batches for methylene blue (MB) and paracetamol (PCT) removal. The results show that, the presence of NPF, which dispersed in the hydrogel PVA_PVP_IC scaffolds containing both covalent and non-covalent cross-linking bonds, greatly enhanced the MB and PCT adsorption efficiency. A response surface methodology (RSM) model was used to find the best operating parameters of contaminant adsorption, including time, adsorbent dose, and starting concentration of pollutants. By using this statistical model, it was found that the optimal conditions for the adsorption reaction to achieve the complete removal of MB are 66.7h adsorption time duration, 98.5mgL−1 starting concentration, and an adsorbent dose of 5.9mg, while for the complete removal of PCT, it is 57.6h adsorption time duration, 80mgL−1 starting concentration, and an adsorbent dose of 6mg. The reusability of the nanocomposite hydrogels were tested for 5 cycles, all showed high adsorption capacity, indicating the potential for practical application of this nanocomposite hydrogel system. This study indicates that the prepared nanocomposite hydrogel raises the standard used for treatment of wastewater and also gives a solution to protect the environment and mitigate global warming.

Optimization of operational parameters of marine methanol dual-fuel engine based on based on RSM- MOPSO

Methanol and natural gas, as green fuels for environmental protection, have shown great potential in the field of maritime transportation. This study explores how the methanol energy fraction (MEF), exhaust gas recirculation (EGR), excess air ratio (λ), and engine injection timing (EIT) influence combustion and emission traits in marine dual-fuel (DF) engine. Initially, a DF engine model was formulated through experiments using CONVERGE software, while the CHEMKIN program devised a chemical mechanism involving 100 compounds and 512 reactions. The response surface methodology (RSM) was subsequently utilized to design the experiment and develop the regression model. The improved multi-objective particle swarm optimization (MOPSO) algorithm was applied to optimize three critical variables: brake thermal efficiency (BTE), carbon monoxide (CO), and nitrogen oxide (NOx) emissions. Ultimately, feature-optimized scenarios from the Pareto front were chosen for comparative evaluation to derive the optimal configuration. The results show that when the decision variables MEF, EGR, λ and EIT are 22.33%, 10%, 1.81 and 11°CA BTDC respectively, there is a better trade-off between the three target variables. Compared with the original case, the change of ITE, NOx and CO emissions in the optimal case are +0.97%, -39.53% and -14.51%, respectively. Overall, based on the intelligent optimization approach, the rational selection of DF engine parameters improved the ITE and most NOx and CO emissions were effectively suppressed.

Microbial symbiotic electrobioconversion of carbon dioxide to biopolymer (poly (3-hydroxybutyrate)) via single-step microbial electrosynthesis cell

This study proposes an novel single-stage microbial electrosynthesis system (MES) that bioelectrochemically converts CO2 into poly(3-hydroxybutyrate) (PHB). This innovative approach utilizes a symbiotic co-culture of electroactive acetogenic bacteria and PHB-accumulating bacteria within a single reactor, bypassing the need for separate acetate production and extraction. Systematic optimization of key operational parameters, including applied voltage, carbon source, and cathode material, was conducted to maximize PHB production. Results demonstrate that using a voltage of 2.5 V yielded a 7.14-fold increase in PHB content compared to open circuit conditions. Furthermore, functionalizing the cathode with a conductive and hydrophilic PEDOT: PSS polymer coating significantly enhanced the system’s performance, resulting in a 1.5-fold increase in both acetate and PHB production compared to unmodified carbon felt electrodes. The long-term stability and effectiveness of the co-culture system were validated through comprehensive microbial and metagenomic analyses. Results revealed a significant enrichment of CO2-utilizing electrotrophs within the cathode biofilm, including Acetobacterium and Clostridium. Concurrently, a 4 to 14-fold increase in the relative abundance of PHB-biosynthesizing bacteria, such as Pseudomonas, Rhodobacter and Caulobacter was observed in the planktonic phase. This study offers a promising pathway towards a circular bioeconomy by enabling the valorization of CO2 into valuable bio-based products via single-stage MES, utilizing a symbiotic co-culture.

Design and performance study of a kilowatt-class PEMFC stack with metal fiber felts as flow fields

The study presents a comprehensive design and evaluation of a kilowatt-class proton exchange membrane fuel cell (PEMFC) stack, wherein stainless steel fiber felts are innovatively utilized as flow fields. The impacts of critical operating parameters, namely operating temperature, pressure, and reactant gas relative humidity, on the performance of the 22-cell stack with an active area of 83 cm2 were thoroughly investigated. An analysis of the voltage consistency among individual cells was conducted across varying operating conditions and output currents. The total power output of the PEMFC stack reaches 1183W under the fundamental operating conditions, where each cell achieves an average voltage of 0.6V. As the operating temperature and pressure are incremented, the stack’s output power exhibits a noticeable increase. The optimal range for the reactant gas relative humidity is found to be 60% to 80%. As the output current increases, the voltages of individual cells gradually decrease and the voltage consistencies tend to deteriorate. The optimal operating conditions for achieving the best voltage consistency vary with current density.

The Study of Removal of Polyvinyl Chloride (PVC) Particles from Wastewater through Electrocoagulation

Plastic was produced massively, especially using polyvinyl chloride (PVC) as a raw material. Unfortunately, this condition cause affects the environment, which creates a new pollutant issue. It is essential to study the removal of PVC microplastics in current water treatment processes. The study of wastewater treatment can be achieved using electrocoagulation, which has several benefits, including low-cost, simple chemicals, and accessible equipment operation. This research investigated the study of the removal of PVC microplastics from wastewater by electrocoagulation. The new potential of the electrocoagulation technique using Al-Al electrodes was studied systematically at various variations, i.e., electrolysis time, electrolyte concentration, initial pH, coagulation speed, and electrolyte type. The results showed that the PVC microplastics removal efficiency reached 100% after electrolysis for 60 min, electrolyte concentration of 0.01 mol/L, initial pH of 7, coagulation speed of 500 rpm, the type of electrolyte used was NaCl at a flocculation speed. These optimum conditions also reduced the value of turbidity of wastewater samples from 1.39 ± 0.02 to 1.10 ± 0.05 NTU. The results of this study provide an engineering perspective in optimizing operational parameters for removing PVC microplastics in aquatic environments.

Synthesis of a triazine based COF and its application for the establishment of an electrochemical sensor for the simultaneous determination of Cd2+ and Pb2+ in edible specimens using Box-Behnken design

The study presented here describes the characterization and synthesis of a triazine-based covalent organic framework using different analytical procedures such as scanning electron microscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, cyclic voltammetry, Brunauer-Emmett-Teller analysis, and electrochemical impedance spectroscopy. The synthesized COF was then utilized as an electrocatalytic modifier for the selective and sensitive determination of Pb2+ and Cd2+ at nanomolar levels via square wave anodic stripping voltammetry. A Plackett-Burman design was employed to screen operational parameters influencing the sensitivity of the electroanalytical method, followed by optimization of the significant variables using Box-Behnken design. A linear response over 1.0–110.0 nmol L−1 and 5.0–300.0 nmol L−1 range for Pb2+ and Cd2+, with detection limits of 1.1 and 1.8 nmol L−1, respectively. Furthermore, the selectivity of the presented electrode over different species was evaluated with no significant interference found. The sensor was applied effectively to determine of Pb2+ and Cd2+ ions in samples.