Journal of Chemical Engineering Research Updates
The Journal of Chemical Engineering Research Updates is a premier publication that provides a comprehensive look at the latest advancements in the field of chemical engineering. With a focus on publishing high-quality, peer-reviewed research articles, review papers, and technical reports, this journal is an indispensable resource for researchers, practitioners, and students alike. The journal covers a broad range of topics within chemical engineering, including process design and optimization, transport phenomena, reaction engineering, materials science, bioprocess engineering, and more. Whether you're working in industry or academia, the Journal of Chemical Engineering Research Updates is an essential tool for staying up-to-date with the latest advances in chemical engineering research. With its focus on interdisciplinary collaboration and its commitment to promoting innovative ideas, the Journal of Chemical Engineering Research Updates provides a wealth of information and inspiration for anyone working in the field of chemical engineering. Whether you're looking to make breakthroughs in research or seeking practical solutions to real-world problems, this journal is a must-read for anyone who wants to stay ahead of the curve in chemical engineering.
All the published articles are licensed under the terms of the Creative Commons Attribution Non-Commercial License (CC BY-NC 4.0) which permits unrestricted, non-commercial use, distribution and reproduction in any medium, provided the work is properly cited.
Targeted Antimicrobial Nanoparticles to Overcome Multidrug Resistance: Mechanisms, Biofilm Strategies, and Translational Challenges
Antimicrobial resistance is advancing at a concerning ratio, challenging the effectiveness of modern medicine. Pathogens responsible for multidrug resistance are now prevalent in public areas such as healthcare facilities, agricultural environments and community settings, limiting treatment options and contributing to higher illness rate and medical costs. These pathogens have become resistant to traditional antibiotics due to their bacterial defence mechanism including efflux pump amplification, enzymatic inactivation, biofilm establishment and genetic exchange. Antibiotics engineered with nanoparticles offer physiochemical characteristics including unique nano-scale size, high surface-area-to-volume ratio, tunable composition via surface modification with targeting ligands, etc., enabling them to evade or disrupt microbial defence mechanisms. This review presents an in-depth analysis of targeted antimicrobial nanoparticles, discussing their design principles, interaction with microbiological resistance pathways, and recent advancements in biofilm penetration, efflux pump inhibition, and enzyme-triggered drug activation. It also highlights microbiology driven nanoparticle, resistance-limiting antimicrobials, while also addressing challenges in safety, large-scale production, and regulatory approval.
Biofilm penetration, Efflux pump inhibition, Targeted drug delivery, Multidrug resistance (MDR), Antimicrobial nanoparticles.
Copyright (c) 2025 Purvi Kishore, Sayoni Maitra https://creativecommons.org/licenses/by-nc/4.0
Comparative Analysis and Optimization of Separation Technique of Carboxylic Acid-Water Mixture Using Aspen Plus
Acetic acid (ethanoic acid) is widely employed as a food preservative, a versatile solvent, and as an intermediate in the synthesis of various industrial chemicals. Recent studies have emphasized process intensification strategies for its separation. Conventional distillation, though straightforward, requires a large number of trays and significant energy input. In contrast, azeotropic and extractive distillation offer improved efficiency with fewer stages and lower energy demand. This study investigates the separation of acetic acid–water mixtures using azeotropic and extractive distillation. Among the azeotropic agents, isobutyl acetate demonstrated lower energy consumption and reduced total annual cost (TAC) compared to vinyl acetate, while achieving high product purity (98.6% acetic acid and 99% water). For extractive distillation, methyl tert-butyl ether (MTBE) exhibited superior performance, yielding 99% purity for both acetic acid and water with minimum energy requirement and solvent usage, outperforming ethyl acetate, which achieved 98.2% acetic acid and 99% water. In comparison, conventional distillation provided only 92.1% acetic acid and 86.4% water. Overall, extractive distillation with MTBE proved to be the most efficient and cost-effective option for acetic acid purification.
Copyright (c) 2025 Ashok Prabhakar, Shivam Raghav, Samridhi, Yashi Mishra https://creativecommons.org/licenses/by-nc/4.0
Preparation of Biopesticide from Custard Apple Seeds (Annona squamosa): A Sustainable Approach
The escalating concerns regarding the environmental and health consequences of synthetic pesticides have driven the exploration of safer and more sustainable alternatives for pest management. This study investigates the preparation of a biopesticide derived from the seeds of Annona squamosa (custard apple), an underutilized agro-waste rich in bioactive compounds, notably annonaceous acetogenins and isoquinoline alkaloids. The developed methodology encompasses systematic seed collection, shade drying, pulverization, Soxhlet extraction using isopropyl alcohol, and solvent recovery through simple distillation. The resulting biopesticide extract exhibited potent insecticidal activity against key agricultural pests—mealy bugs (Phenacoccus solenopsis), caterpillars (Spodoptera litura), and plant lice (Aphidoidea spp)—in controlled laboratory assays. Mortality rates exceeded 80% at optimized concentrations within 48–72 hours post-application, with minimal non-target impact. The novelty of this work lies in its demonstration of a low-cost, solvent-efficient, and scalable extraction process using a common laboratory Soxhlet apparatus to produce a natural biopesticide from agro-waste, yielding ≥18% bioextract with consistent bioefficacy and >90% solvent recovery. Unlike previous studies that focused on crude methanolic or aqueous extracts, this research delivers a semi-purified formulation with confirmed stability and repeatable insecticidal performance. Additionally, comparative analyses reveal advantages over conventional synthetic pesticides in terms of biodegradability, ecological safety, and target specificity. This study highlights the immense potential of A. squamosa seeds in promoting circular bioeconomy approaches and delivering eco-friendly pest management tools, contributing significantly to sustainable agriculture and integrated pest management systems.
Copyright (c) 2025 P. Balaganesh https://creativecommons.org/licenses/by-nc/4.0
Pectin-based Bioink and Bioprinting Parameter Optimization and Industrialization
Bioprinting for tissue engineering and regenerative medicine offers a promising solution to the growing demand for organ transplants. A pectin-based bioink was engineered to offer cost-effectiveness and operational simplicity. This project focuses on the commercialization and industrial production of this bioink. The bioink formulation and bioprinting parameters for extrusion-based bioprinting were optimized, as extrusion-based bioprinters are most commonly used in bioprinting. The optimization process focused on structural integrity, resolution, and cell viability. Additionally, an industrial-scale production process was designed using SuperPro Designer. The bioink formulation with optimized bioprinting parameters shows great potential for extrusion-based bioprinting with scalable manufacturing capabilities.
Copyright (c) 2025 Alexis Berka, Aidan Callahan, Sonia Grade, Benjamin Lilienkamp, Annika Peters, Rebecca Salzman, Mason Dopirak, Wujie Zhang https://creativecommons.org/licenses/by-nc/4.0
Ultra-Low Emission Strategies in Steel, Coking, and Cement Industries: Pathways to Decarbonization and Sustainability
Steel, coking and cement industries make up nearly 30% of global industrial CO2 emissions and are key to becoming net-zero. Although earlier research usually looked at each industry in isolation, this paper provides an overview of ULE strategies that examines both technology and policy together across the various industries. Recent improvements in hydrogen-based steelmaking, molten oxide electrolysis, coke dry quenching, catalytic reforming coke oven gas, alternative binders for cement and carbon capture are synthesized and evaluated for capacity, costs and environmental impact. The review uniquely compares what causes emissions in different sectors, how far away each technology is from being fully developed, how far digitization has advanced and what roadblocks stand in the way. The paper introduces new results on CO2 control, energy used in processes and marginal abatement costs to evaluate the practical feasibility of new technologies. AI controls, modular CCUS, hydrogen infrastructure and the industrial symbiosis framework are explored in terms of how they push the sector into transformation. Ultimately, the review suggests areas of research and policy such as combining electrification and CCUS into systems, creating free-to-use lifecycle tools and reforming institutions to support ULE use in SMEs and developing areas. This review sets out roadmaps using several approaches that show how ULE strategies could be applied across hard-to-abate sectors with both technical and institutional support.
Copyright (c) 2025 Koti B.T. Vagdandam, Prathyusha T., Dilip K. Behara https://creativecommons.org/licenses/by-nc/4.0
Innovative Biosorbents from Agro-Waste: Advancing Sustainable Solutions for Heavy Metal, Dye, and Organic Pollutant Removal
Ensuring clean water and safe food remains a global challenge due to the rising contamination of natural resources by heavy metals, dyes, and organic pollutants. This review highlights innovative, low-cost, and eco-friendly biosorbents derived from agricultural waste, presenting a comprehensive overview of their application in wastewater treatment. Unlike conventional reviews, this study categorizes a wide range of agro-waste materials including fruit peels, shells, husks, and plant residues according to their sorption properties and pollutant specificity. Notably, biosorbents such as activated carbon from rice husk, coconut shells, and banana peels demonstrated high adsorption capacities (up to 744.39 mg/g for dyes and 480.9 mg/g for heavy metals) under optimized conditions. The review further provides an in-depth analysis of chemical, thermal, and magnetic modifications that significantly enhance adsorption performance and selectivity. A key contribution of this work is the original economic analysis of these biosorbents, revealing their cost-effectiveness (as low as 0.49 €/kg) and practical scalability compared to commercial activated carbon. By integrating recent advancements, environmental implications, and regeneration potential, this review offers a valuable roadmap for researchers and practitioners aiming to implement sustainable, circular economy-based solutions in water purification systems.
Copyright (c) 2025 Mehwish Kiran, Fazal Haq, Sahid Mehmood, Tariq Aziz https://creativecommons.org/licenses/by-nc/4.0
Process Simulation of Wet Flue Gas Desulfurization
During combustion in power plants, sulfur in coal forms SO2, a key air pollutant causing acid rain. Denitrification of SO2 in exhaust gases is crucial, and simulation is a practical research approach. This article applies Aspen Plus software to simulate and optimize the limestone-gypsum wet flue gas desulfurization process. The results show that the established model can effectively reduce SO2 content, achieving a desulfurization rate of 95.9%, which verifies the feasibility of the process flow. Through sensitivity analysis and orthogonal experiments, it is found that the inlet temperature of flue gas, calcium-sulfur ratio, and water content in limestone slurry are the key factors affecting the desulfurization efficiency. The optimal operating parameter combination is an inlet temperature of flue gas of 80°C, a calcium-sulfur ratio of 1.03, and water content in limestone slurry of 35 kmol/hr, with the calcium-sulfur ratio having the most significant impact on desulfurization efficiency. The study indicates that the combination of this software and the process has good application prospects.
Copyright (c) 2024 Changhong Li, Baiqiang Zhang, Junhui Li, Yanhao Hu https://creativecommons.org/licenses/by-nc/4.0
Characterization and Analysis of Gas-Solid Flow Dynamics in Fluidized Bed Systems
Fluidization is a critical process in various industrial applications, particularly in the oil and gas sector, where it plays a pivotal role in optimizing production, phase separation, and the efficiency of mass and heat transfer, as well as chemical reactions involved in physical and chemical operations. The significance of fluidization stems from its direct impact on key parameters such as pressure drop, flow velocity, particle concentration, and void fraction in multiphase flows. In this context, fluidization enhances the interaction between fluid and solid particles, reducing resistance to heat and mass transfer and promoting material homogenization. This experimental study aims to investigate the flow behavior of a particulate system within a fluidized bed, specifically focusing on the fraction of the continuous (gas) phase relative to a defined volume of solid particles. The results obtained, when compared to existing literature primarily concerned with the effects of particle size and flow rate on fluidization, demonstrate consistency in both qualitative and quantitative analyses. These findings suggest that the increase in the volume of the continuous phase in such flows is strongly influenced by the Reynolds number and the particle size within the system. Thus, this study makes significant contributions to the optimization of fluidization processes, particularly in industrial sectors like oil and gas. By providing detailed experimental insights into the factors that influence fluidized bed performance, the findings offer practical implications for improving the efficiency of heat and mass transfer, phase separation, and reaction rates in industrial applications where the behavior of the continuous phase is crucial.
Copyright (c) 2024 Elaine M.G. de Araújo, Emerson Barros, António A.C. Barros https://creativecommons.org/licenses/by-nc/4.0
Effect of Hot-rolling Deformation on Microstructure and Mechanical Properties of Nd2Fe14Bp/Al-5Co-0.4Sm Composites
Nd2Fe14Bp/Al-5Co-0.4Sm composites were prepared via microwave sintering and hot rolling. The effects of hot-rolling deformation on the microstructure and mechanical properties of Nd2Fe14Bp/Al-5Co-0.4Sm composites were studied. The results showed that the internal porosity of the composites significantly decreased when the hot-rolling deformation rate was 45%. The Nd2Fe14B particles were broken into fine particles under rolling stress. Consequently, the particles were uniformly distributed. Moreover, numerous high-density dislocations were observed around the particles, which improved the strength and toughness of the material. When the deformation rate was 45%, the micro-nano hardness and elastic modulus of the interface of the composites were 3.6 and 91 GPa, respectively. The interfacial deformation resistance of the composites was significantly higher than that of the composites before rolling. The tensile strength of Nd2Fe14Bp/Al-5Co-0.4Sm composites increased as the deformation rate increased, whereas the elongation gradually decreased. Furthermore, when the deformation rate was 45%, the tensile strength and elongation of the composites were 161 MPa and 6.5%, respectively. The tensile strength was 14.2% higher than that of the unrolled sample.
Copyright (c) 2024 Huang Jun-jie, Huang You-wei, He Jia-xin, Kang Ma, Wang Hong-ming https://creativecommons.org/licenses/by-nc/4.0
Antisolvent Crystallization (ASC) in Aqueous System: Fundamentals, Sustainability Aspects, and Applications
The present perspective focuses on fundamental and applied attributes of antisolvent crystallization (ASC) in aqueous systems and establishes its potential for various industrial applications. In the ASC method, supersaturation is attained by adding a secondary solvent (antisolvent) to a solution leading to the crystallization of the solute. ASC offers the advantages of increasing yields, and conserving energy over the conventional evaporative or cooling crystallization, and thus appears to be a growing industrially important and sustainable process. The insights on the role of phase equilibrium thermodynamics and kinetics in controlling the crystallization process and crystal properties during ASC are discussed. The choice of solvents is a critical factor in ASC, and the solvent type, properties, and selection are considered briefly. The evaluation of the sustainability aspect of ASC by assessing the environmental benignity of solvents, the impact of their life cycles on the ecology, and associated economic costs are presented. A comprehensive list of solvents used for ASC and their usage pattern is also included. Successively reintegrating ASC into process design and developing different process configurations (stand-alone and hybrid) are reviewed. Finally, the paper highlights the opportunity for more widespread application of ASC in the fields of salt extraction, water treatment, hydrometallurgy, bioprocessing, and the pharmaceutical industry.
Copyright (c) 2024 Sameer Bhatti, Parul Sahu https://creativecommons.org/licenses/by-nc/4.0
Recent Advances in Chitosan-based Nanocomposite Membrane Materials for Water Treatment
In recent years, research on chitosan (CS)-based nanocomposite membranes has made significant progress in the field of water treatment. This innovative membrane material incorporates a variety of excellent biological properties, including the biocompatibility and adsorption properties of the natural polymer chitosan (CS) and the introduction of nanotechnology. Furthermore, it enables the composite material to have excellent functional characteristics, such as higher water flux and selectivity. Furthermore, the enhancement of the structural and intrinsic properties of membrane materials will facilitate the attainment of further advancements in a multitude of performance characteristics, including stability, durability, and adsorption selectivity. Consequently, this field has become a promising area of research in water treatment technology, attracting extensive research and attention. However, the publication of a large number of related research reports in recent years, accompanied by numerous and complex performance optimization schemes and research ideas, has resulted in a paucity of articles that summarize these performance optimization strategies and research paths. Consequently, there are few meaningful references for subsequent research. In light of the aforementioned considerations, this paper will provide a comprehensive review of the most recent research advances in the field of water treatment, with a particular focus on the latest research strategies and frameworks for optimizing the performance of related materials. Furthermore, this paper will illustrate the innovative and beneficial applications of such materials from various vantage points, including their sources and preparation processes. It is anticipated that this paper will serve as a valuable source of inspiration for further research in this field.
Copyright (c) 2023 Ziao Zhang, Yujie Lu, Yiman Zhao, Shuping Wu https://creativecommons.org/licenses/by-nc/4.0
Review of Recyclable Bio-based Epoxy Resins with Dynamic Chemical Bonds
Epoxy thermosetting resins are usually reliant on fossil fuel-based resources, commonly diglycidyl ether bisphenol A (DGEBA) type epoxy monomers. Most raw materials of these thermoset resin are toxic to the health of human, and their eternal cross-links make them difficult to reuse and recycle. To alleviate concerns about the environment and human health, it is an effective way to design new bio-based epoxy thermosetting materials to replace petroleum based thermosetting materials. The introduction of cleavable and dynamic bonds for bio-based thermosetting materials can also realize the recycling of bio-based epoxy resin. In this way, the damaged thermosetting materials can be recovered to prolong their service lifetime and reduce the thermosetting waste. This review article aims to outline the latest improvements in intrinsically recyclable bio-based epoxy thermosetting materials. This review first describes the synthesis method of recyclable bio-based epoxy, then reviews the structure, recyclable and other properties of bio-based epoxy containing different dynamic bonds, and finally summarizes the challenges and opportunities for the recyclable bio-based epoxy.
Copyright (c) 2024 Mengting Wan, Xuemei Liu, Yuan Zhang https://creativecommons.org/licenses/by-nc/4.0
A Study on Failure Rate, Reliability, and Collection Efficiency Trend of Bag Filters in a Cement Plant
This thesis presents a comprehensive study on the failure rate, reliability, and collection efficiency trends of bag filters in a cement plant over 15 years. Bag filters are vital pollution control equipment used in various industries, including cement plants, to maintain environmental compliance. Understanding their performance and failure patterns is crucial to ensure efficient and reliable operation while adhering to stringent pollution control standards. The research findings reveal that the failure rate trend of bag filters closely follows the bathtub curve, with an initial high failure rate, a period of lower failures, and a subsequent increase in failures as the equipment nears the end of its life cycle. Reliability trends align with Madhab's Hat curve, exhibiting higher reliability during the first 10 to 12 years of operation, followed by a decline in reliability. The collection efficiency of bag filters declines as the equipment ages, with the efficiency decreasing from 99.998% in the early years to 95.05% in the 15th year. This emphasizes the importance of maintenance and retrofitting for older dust collection equipment to maintain high collection efficiency. The study concludes that the typical life span of bag filters ranges from 10 to 15 years, after which major maintenance interventions are necessary to minimize failure rates. The research provides valuable insights for maintenance engineers, design engineers, and reliability engineers, enabling them to improve the performance of pollution control equipment, such as bag filters, reverse air bag houses (RABH), and electrostatic precipitators (ESP), to meet the pollution control standards set by regulatory authorities.
Copyright (c) 2023 Madhab C. Jena, Sarat K. Mishra, Himanshu S. Moharana https://creativecommons.org/licenses/by-nc/4.0
Enzymatic Treatment of Cotton Fabric for Desizing
The possibility of softening the conditions of biochemical treatment to remove the sizing agent from the surface of the fibers in the preparation of cotton fabric for dyeing has been studied. The efficiency of the α-amylase enzyme was evaluated by the amount of sugars reduced in the modifying solution, as well as by the capillarity of the samples of the treated fabrics. The enzyme used is active towards starch starting from a low concentration (0.02 g/l) and low temperature (32°C). The effect of enzyme concentration from 0.02 to 6.0 g/l, solution pH from 4.5 to 8.5, temperature from 32 to 60°C on the amount of sugars in the solution after enzymatic treatment, and fabric capillarity was determined. Almost complete removal of sizing from the surface of fibers of the original fabric was achieved under moderate and mild processing conditions: α-amylase concentration 1.0÷5.0 g/l, pH=6.0÷7.0, temperature 50-55°C. Based on the dependence of the logarithm of the reaction rate on the reciprocal temperature, the activation energy of the desizing reaction was calculated, which turned out to be equal to E = 17.5 kJ/mol. The low activation energy shows that the desizing process is carried out under energetically favorable conditions with moderate heating. The surface morphology of treated and untreated samples of cotton fabric was studied by scanning electron microscopy. The removal of the adhesive substance from the surface of the fibers, the separation of individual fibers, and the smoothing of the fabric surface after treatment with an amylase solution were recorded.
Copyright (c) 2023 Adham S. Rafikov, Kamola Fayzullaeva, Tulkin E. Shonakhunov, Dilnoza B. Qizi Soyibova, Nataliya N. Yasinskaya https://creativecommons.org/licenses/by-nc/4.0
Water Sustainability Initiatives to Meet the Water Crisis in India
One of the most pressing global challenges we face today is the rapid growth of the population. As the population continues to expand, the need for rapid industrialization has become paramount. However, this industrialization and urbanization have given rise to a significant and detrimental consequence: environmental pollution. This pollution, in turn, has led to various crises, including those related to water, food, and air quality. Water, being an essential element for human existence, is of utmost importance. Without access to clean and sufficient water, life on Earth would be unsustainable. Unfortunately, India has been grappling with a prominent water crisis, particularly during the summer seasons, resulting in the loss of countless lives each year. Even during other seasons, the availability of water is often satisfactory, but the quality of water remains a concern in many parts of the country. The shortage of water can be attributed primarily to the declining levels of underground water and the ever-increasing demand for this precious resource. India receives ample rainfall during the monsoon season; however, a significant portion of this water flows into the oceans, causing floods in various regions. Conversely, during the summer months, the scarcity of water leads to droughts in many areas. Therefore, it is imperative to initiate sustainable water management practices, including rainwater harvesting, to address this water crisis. This review article delves into various types of water sustainability initiatives with a structured approach and analyzes the associated challenges. Additionally, it proposes detailed systems that can be implemented to enhance water availability and distribution throughout the country. These measures are crucial steps toward mitigating the water crisis and ensuring a sustainable water future for India.
A Comprehensive Review on Third-Generation Photovoltaic Technologies
The renewable energy industry has revolutionized due to photovoltaic (PV) technologies, which offer a clean and sustainable alternative to conventional energy sources. Third-generation photovoltaic technologies refer to a group of emerging PV technologies aiming to surpass the efficiency and cost-effectiveness of traditional silicon-based solar cells. Different ceramic materials have also been investigated for use in these advanced PV technologies. This review examines the science, current state, and advancements of third-generation PV systems for wide-scale implementation. The first section of this study provides an overview of the development of PV technologies from the first to the third generation, highlighting the most significant novel developments made at each step. Organic photovoltaic (OPV) cells, dye-sensitized solar cells (DSSCs), and perovskite solar cells (PSCs) are discussed here as a few new technologies that constitute the third generation, also known as the next generation of advanced PV. This review presents how these devices can be used in specialized settings, including indoor and low-light environments, thereby expanding the range of energy harvesting potential. The brief history of these emerging technologies, their current status, future developments, and key challenges are discussed in this review paper.
Copyright (c) 2023 Arko De, Jyoti Bhattcharjee, Sahana R. Chowdhury, Subhasis Roy https://creativecommons.org/licenses/by-nc/4.0
Solar Distiller Study for Freshwater Production by Seawater Desalination
Water covers 70% of the planet Earth. Of the total volume of water on the planet, 2/3 (two-thirds) is in the form of ice or underground water. On the other hand, fresh water is an increasingly scarce resource in the world, with only 3% of the world's water being drinkable. Data from the United Nations (UN), indicate that approximately 1.1 billion inhabitants on planet Earth do not have access to fresh water. The same data also reveal that 2.7 billion inhabitants suffer from water scarcity for approximately one month a year. According to these data, water scarcity currently affects more than 40% of the world's population. This condition has driven the proposition of technological solutions to minimize the impact of difficulties in accessing this good [1]. Allied to all these aspects, in recent decades, industrial development and the growth of the world population have demanded a greater need for fresh water. At the same time, pollution and the reduction of surface water sources limit access to available freshwater resources [2]. Thus, there is a need for alternative water sources, leading to a focus on using previously technologies, with an emphasis on saltwater desalination. Many areas affected by freshwater scarcity are close to the sea, favoring implementing these technologies.
Copyright (c) 2022 Antonio Andre Chivanga Barros, Adilson Narciso Francisco Pinto, Mário de Assunção Afonso Futa, Albino Joaquim Ngola, Chikunda Amões, Chelson Oliveira, Peterson Alves, Elma Mateus, Carlos Minunsidi, Tommaso de Pippo, Filipe Silvino de Pina Zau, Henrique Afonso https://creativecommons.org/licenses/by-nc/4.0
Behavior in Oxidation at 1000°C of Carbon-Containing Equimolar CoNiFeMnCr Alloys Added with Hafnium or Tantalum with High Contents
In this work, HfC–and TaC–reinforced cast versions of the equimolar CoNiFeMnCr alloy (Cantor) were tested in oxidation at 1000°C in laboratory air. Chromium seemingly shared, with manganese, its role as a selectively oxidized element. The principal oxide to form externally was an M2O3 one in which Mn and Cr were present in various proportions depending on the proximity with the alloy’s surface. The HfC carbides close to the oxidation front were oxidized in situ in HfO2, with the release of carbon diffusing inwards after that and inducing the solid-state precipitation of blocky or acicular chromium carbides. The behavior of the TaC carbides present close to the oxidation front was different since they dissolved, and Ta diffused towards the oxidation front to form CrTaO4 oxides. Even after 50 hours at 1000°C, the subsurfaces were more or less deeply impoverished in Cr and Mn, with minimal contents meager, especially for Mn. The evaluation of the Cr and Mn quantities and the exploitation of results in terms of equivalent oxide thickness and kinetic oxidation constant demonstrates that the resistance of the alloys against oxidation is feeble and must be significantly improved to allow benefiting of the superior high-temperature mechanical resistances of such alloys in practical application. For that, some ways are proposed.
Copyright (c) 2022 Patrice Berthod https://creativecommons.org/licenses/by-nc/4.0
Experimental Verification for Numerical Flow Analysis in Mixing Vessel
Visualization of a streak line pattern in a mixing vessel is quite useful for understanding the mixing mechanism and designing an optimal mixing vessel. However, conventional experimental methods for visualizing streak lines require a lot of time to construct impellers and prepare solutions. Although various commercial fluid analysis software has been developed, there are still no examples of its use for calculating streak lines in mixing vessels. A simulation method was developed to quickly evaluate the streak line pattern in a laminar mixing vessel by numerical analysis with commercial code. A commercial CFD code can calculate streak line patterns in a laminar mixing vessel. It was found that a lattice method was more suitable than a particle method for the simulation of the streak line.
Copyright (c) 2022 Masaya Kano, Haruki Furukawa, Yoshihito Kato, Yuta Tanemori, Yuya Shudo, Takahito Mitome, Tsuyoshi Yamada, Kazuhiro Yamashita https://creativecommons.org/licenses/by-nc/4.0
A Double Salt Formation from Seawater Bittern and Ammonium Sulfate
Seawater bittern, a huge reserve containing numerous mineral materials, is an essential source for producing various industrial salts. In this work, the formation of a double salt between magnesia abundant in the seawater bittern and ammonium sulfate was studied via SEM and EDX analyses. In the next step, to optimize the efficiency of the double salt separation, the effects of technological parameters such as concentration of reactants and their ratio, as well as reaction time and temperature, were investigated. Afterward, the design of the experimental method was utilized to quantify the influence of these parameters. Based on the validation of the obtained model according to statistical criteria, only the ratio of reactants and reaction time have been shown to have decisive roles in the yield of the double salt recovery. The optimal yield reached a value of about 95%, demonstrating the feasibility of the applied technique for further processes, i.e., industrial production.
Copyright (c) 2022 Tam Minh Le, Phuong Thi Hong Pham, Nam Dong Hoang https://creativecommons.org/licenses/by-nc/4.0
The Influence of Concentration on the Formation of Chemical Bath Deposited Copper Tin Sulphide Thin Films: SEM and EDX Studies
Nanostructured copper tin sulphide films have been deposited on the substrate (soda lime glass) via an economical chemical bath deposition method. The scanning electron microscopy (SEM) technique and energy dispersive X-ray analyzer (EDX) method were employed in this work to study the films’ morphology and composition. The EDX data and SEM images confirmed that the content of elements (sulfur, tin, and copper), the shape, and the grain size strongly depended on the concentration of the precursors during the formation of films. Experimental results revealed that a higher atomic percentage of the element could be observed for the films prepared using a higher concentration of solution during the experiment.
Copyright (c) 2022 Ho Soonmin https://creativecommons.org/licenses/by-nc/4.0
Validation of Solar Dehydrator for Food Drying Applications: A Granny Smith Apple Study
Food loss is a global issue that may be alleviated with effective dehydration strategies. Solar dehydration, rather than traditional sun-drying, is one method that could allow for the safe, efficient preservation of food materials. In this study, passive solar dehydration was achieved using a psychrometric chamber to model the environment of sub-Saharan Africa, where the temperature was the major focus (24.3 °C to 29.4 °C). A mass decrease of 88.56% was achieved within 9 hours. Microbial testing (total aerobic bacteria, Gram-negative bacteria, and total yeasts and molds) demonstrated no difference (all negative) between food stored at 4 °C and dehydrated food, indicating that the dehydrator introduced no new contamination. A 16.0% decrease in vitamin C (VC) concentration was observed due to the lability of VC. Insight into the visual appeal of the food samples was provided by measuring browning values, where it was found that dehydrated green apples are significantly less brown than the sample exposed to air for the same length of time. Passive solar dehydrators could provide a simple method to reduce food waste and maintain nutritional content and visual appeal.
Copyright (c) 2022 Jude Ingham, Muskan Kanungo, Brandon Beauchamp, Michael Korbut, Michael Swedish, Michael Navin, Wujie Zhang https://creativecommons.org/licenses/by-nc/4.0
Characterization of Filmogenic/Edible Covering Based on Pectin Extracted from Cajá (Spondias mombin) Applied to Coating Green Acerolas (Malpighia emarginata)
Filmogenic coatings can be used as a post-harvest strategy to extend shelf life and ensure improvements in fruit quality and safety given their perishable nature. Due to their edibility, the composition of the coverings is a determining factor for their application, and for this reason, it is interesting and desirable that the constituents come from natural sources. The objective of the present study was to develop and characterize a pectin-based film extracted from cajá peel (Spondias mombin) and verify its efficiency as an edible coating in postharvest acerolas (Malpighia emarginata). The film was characterized in terms of mechanical properties by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM); as well as in terms of chemical properties using the analysis of structural bonds by Fourier Transformed Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). In addition, the antimicrobial activity against two bacteria was evaluated. The analyzed film was presented as a dense membrane, with the presence of pores, fissures, and a very rough surface. The degree of esterification of pectin extract from cajá peel was 44%, and for this reason it was classified as low methocxyl (LM) pectin. The filmogenic solution presented antimicrobial activity against the bacteria Pseudomonas aeruginosa and Staphylococcus aureus. The applicability of the edible coating was tested on green acerolas, monitoring their maturation stage through analyzes such as weight loss, titratable acidity, and total soluble solids. At the end of the 7 days of storage, acerolas with the application of the coating showed 8.97% weight loss while acerolas without coating showed 9.89%; the percentage of total soluble solids was 7.68% higher for acerolas with the coating, as well as ascorbic acid content was higher for the protected fruits, indicating that the coverage favored the delay in the maturation of acerolas.
Copyright (c) 2021 Estéfani Alves Asevedo, Sérgio Dantas de Oliveira Júnior, Everaldo Silvino dos Santos https://creativecommons.org/licenses/by-nc/4.0
Design of Experiment Method – An Application in Improving Quality of Magnesium Hydroxide Produced from Natural Seawater Bittern
Seawater bittern is an important resource for production of magnesium hydroxide. It is particularly meaningful for countries of which long beaches and high temperatures are available as natural advantages. This production process bases on the main reaction between solutions containing magnesium and various alkaline agents. Among of precipitants, lime slurry is frequently used as an inexpensive reactant. However, the contamination of calcium in the final magnesium hydroxide is a major problem which limits applicability of this product in many fields required extremely high quality of magnesium hydroxide such as pharmaceuticals, and catalyst, etc. In this work, magnesium hydroxide with more than 99% purity will be recovered from natural seawater bitterns by using the design of experiment (DOE) method. Selected from nine potential factors, a full factorial design considering four main effects was applied to construct a second-order regression model which allows predicting favorable conditions to pursuit high purity of magnesium hydroxide from multi-component seawater bittern and lime milk. On the one hand, the results for a 1.0 L batch investigation proved that factors such as concentration of Ca(OH)2 in lime suspension and residence time have strong negative influences on the product purity, besides positive effects of reaction temperature. On the other hand, magnesium concentration in the bittern was absent in the regression model. At the optimal conditions, the chemical purity of the solid product was obtained at a value of 99.35%. Thus, this product, and therefore its corresponding production conditions, can be recommended for applications required high quality of magnesium hydroxide.
Copyright (c) 2021 Tam Le-Minh, Nam Hoang Dong, Dzung Nguyen Tan https://creativecommons.org/licenses/by-nc/4.0
A Pilot Study of a Hybrid Process Involving In Situ Regenerated Activated Carbon, Membrane Separation and Advanced Oxidation for Water Pollution Abatement
The assessment of a pilot-scale hybrid system coupling powdered activated carbon (PAC) adsorption with membrane ultrafiltration (UF), in respect of activated carbon regeneration and organic micropollutant removal, was investigated in this study. Field tests with two adsorbents (i.e. a commercial PAC and a PAC-Fe(II) composite), conducted in the premises of Thessaloniki Water Treatment Plant, demonstrated the high efficiency of the combined PAC/UF process. Regeneration efficiencies varying between approximately 95% and 110%, complete diclofenac (DCF) degradation and rather moderate mineralization (TOC removal) rates of up to 47%, can be achieved by UVC/H2O2 or photo-Fenton oxidation after 4 hours of treatment; this performance is attributed to the in situ generation of reactive oxidant species by photolysis of H2O2, which seems to enhance the process effectiveness. Among the two adsorbent materials tested, composite PAC-Fe(II) exhibited a higher DCF adsorption capacity than the original PAC, probably due to the improved chemisorption and/or the electrostatic attractive interactions between the negatively charged DCF molecules and the positively charged iron species, at neutral pH. Furthermore, a rather insignificant effect of PAC-Fe(II) loading on the regeneration efficiency was observed. The advantages of totally controlled H2O2 dosages and short operating times render the hybrid PAC/UF system a promising alternative to conventional and advanced drinking water purification methods.
Copyright (c) 2021 Vasilis C. Sarasidis, Konstantinos V. Plakas, Anastasios J. Karabelas https://creativecommons.org/licenses/by-nc/4.0
Synthesis and Potential Applications of Modified Xanthan Gum
Designing high-performance adsorbents for wastewater treatment and antibacterial materials for food and biomedical applications and excellent drug carrier to prolong time retention of the therapeutic drug based on biodegradable polymers has gained more interest in recent years. Among these materials, xanthan gum, which is a natural polysaccharide and plays a vital role in various applications such as industry, enhanced oil recovery, water-based paints, pharmaceuticals, and personal care products because it has excellent properties such as biodegradability and non-toxicity. On the other hand, it has many affected limitations, including microbially attack, poor thermal and mechanical stability, and low surface area. So, in this review, we focused on the advanced modifications on xanthan gum and their applications in wastewater treatment, protein delivery, and designing antimicrobial materials.
Copyright (c) 2021 Mahmoud H. Abu Elella https://creativecommons.org/licenses/by-nc/4.0
Photocatalytic Reduction of Cr(VI) and Degradation of Organic Pollutants by Z-Scheme g-C3N4/Bi2S3 Heterojunction
Photocatalytic reduction of hexavalent Cr(VI) couping oxidative degradation of organic contamination is an emerging and practical approach for water treatment. In this study, Z-scheme g-C3N4/Bi2S3 heterojunctions with intimate interface were successfully synthesized by direct growth of Bi2S3 on g-C3N4 surface. Notably, the photocatalytic performance of Z-scheme g-C3N4/Bi2S3 was influenced by g-C3N4 content. The optimized 2% g-C3N4/Bi2S3 heterojunction shows the highest photocatalytic reduction performance with 93.4% reduction efficiency of Cr(VI) under UV-visible light due to efficient separation and transfer of charge carriers and proper band structure. Furthermore, 2% g-C3N4/Bi2S3 can degrade tetracycline and Rhodamine B. Free radical capturing and quantitative tests indicate that holes and superoxide radicals are primary active species for the degradation of organic pollutants, while Cr(VI) was reduced to Cr(III) by the photogenerated electrons. Overall, this study provides new insight into the synthesis of high-performance Z-scheme heterojunctions for the future advancement of photocatalysis technology.
Copyright (c) 2022 Lin Ding, Ying Deng, Xinggang Liu, Lingling Liu, Jingjing Ding, Fang Deng https://creativecommons.org/licenses/by-nc/4.0
Frost Heave and Ice Lenses Formation in Freezing Soils
A generalized model for secondary frost heave in freezing fine-grained soils is presented and discussed. The cryostatic suction effect, which increases upward water permeation, ice-lens growth during freezing, and, as a consequence, the increase of soil heave, is considered to be the main mechanism of moisture transfer. We recognize the need to determine the distribution of the moisture within the frozen fringe by approximation of the experimental data for the equilibrium unfrozen water content. This distribution is the result of the complicated interaction between water, ice and the mineral skeleton during the freezing process. The generalization of the Clapeyron relation, which is used in the studies of other authors, estimates only the drop in initial freezing temperature and does not define the connection with the external temperature gradient ∆T, which is responsible for the frost heave process. This very important aspect is discussed in detail in the introduction to our paper. We take also into account the ratio Pe/Ste # 1 (where Pe<<1). This approach allows us to obtain a more general solution. The criterion of the ice lenses formation in fine-grained soils and the model for calculation of the lenses' thickness and spacing are derived. The dynamics of the lenses formation in histogram form is presented and discussed. The theoretical results obtained from the solution for fine-grained soils are compared in good agreement with experimental investigations. The model presented predicts the frost heave and ice lenses formation in freezing soils with reasonable accuracy, satisfactorily reflects observed phenomena, and thus can be suitable for engineering practice.
Copyright (c) 2014 Leonid Bronfenbrener https://creativecommons.org/licenses/by-nc/4.0
Carbonization Kinetics of Various Biomass Sources
Hazelnut shell, apricot stone, grapeseed and chestnut shell samples were carbonized in a thermogravimetric (TG) analyzer at different conditions to determine the carbonization kinetic parameters. Three different calculation methods and 22 different model equations concerning solid-state rate controlling mechanisms were used for the kinetic analysis of the carbonization TG curves. A computer program in BASIC which enables regression analysis, was used to calculate the kinetic parameters from experimental TG data. It was observed that the different values of Arrhenius parameters (E and Log A) were obtained depending on the method of calculation, the gaseous atmosphere and the sample properties. The most appropriate kinetic model which represents the carbonization of the cellulosic and lignin ingredients of the biomass samples were found as f(α)=(1−α)2 and f(α)=0.5·(1−α)·[−ln(1−α)]−1, respectively.
Copyright (c) 2014 Didem Özcimen, Ayşegül Ersoy-Mericboyu https://creativecommons.org/licenses/by-nc/4.0
Production and Purification of Fungal Milk Clotting Enzyme from Aspergillus candidus
The search for rennet substitutes such as microbial rennet has increased fold due to increase in the demand for cheese products. Microbial rennet covers about one-third of the cheese consumption worldwide. Hence it is important to develop commercially viable and cost efficient method for purification of rennet from microbial sources. Hence the present work was focused on the production and purification of microbial rennet from Aspergillus candidus. The rennet was purified using a two step purification process involving solvent precipitation and chromatographic separation. The purity of the milk clotting enzyme was increased by 7.43 fold by solvent precipitation using equal mixture of 150% (v/v) ethanol-acetone. Then the enzyme was further purified using Diethylaminoethyl (DEAE) cellulose chromatography and 10.45 fold increase in enzyme activity was obtained after purification. The temperature of 35°C and substrate concentration of 0.25 mg/ml were found as optimum for maximum enzyme activity. The kinetics of the purified enzyme was studied and the Michaelis-Menten parameters such as rate constant (Km) and the maximum reaction rate (Vmax) were found as 0.059 mg/ml and 8.59 x 10-3 mmol/ml/sec respectively.
Copyright (c) 2014 G. Baskar, S. Babitha Merlin, D.V. Sneha , J. Angeline Vidhula https://creativecommons.org/licenses/by-nc/4.0