Search results for: refining
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 131

Search results for: refining

71 Artificial Intelligence-Based Thermal Management of Battery System for Electric Vehicles

Authors: Raghunandan Gurumurthy, Aricson Pereira, Sandeep Patil

Abstract:

The escalating adoption of electric vehicles (EVs) across the globe has underscored the critical importance of advancing battery system technologies. This has catalyzed a shift towards the design and development of battery systems that not only exhibit higher energy efficiency but also boast enhanced thermal performance and sophisticated multi-material enclosures. A significant leap in this domain has been the incorporation of simulation-based design optimization for battery packs and Battery Management Systems (BMS), a move further enriched by integrating artificial intelligence/machine learning (AI/ML) approaches. These strategies are pivotal in refining the design, manufacturing, and operational processes for electric vehicles and energy storage systems. By leveraging AI/ML, stakeholders can now predict battery performance metrics—such as State of Health, State of Charge, and State of Power—with unprecedented accuracy. Furthermore, as Li-ion batteries (LIBs) become more prevalent in urban settings, the imperative for bolstering thermal and fire resilience has intensified. This has propelled Battery Thermal Management Systems (BTMs) to the forefront of energy storage research, highlighting the role of machine learning and AI not just as tools for enhanced safety management through accurate temperature forecasts and diagnostics but also as indispensable allies in the early detection and warning of potential battery fires.

Keywords: electric vehicles, battery thermal management, industrial engineering, machine learning, artificial intelligence, manufacturing

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70 Microstructure and Properties of Cu-Bearing Hypereutectic High Chromium Cast Iron

Authors: Liqiang Gong, Hanguang Fu

Abstract:

In order to further improve the wear resistance of Hypereutectic High Chromium Cast iron (HHCCI), the effects of different Cu contents on the microstructure and properties of HHCCI were systematically studied. It was found that with the increase of Cu content, the carbide size was refined, and the increase of Cu content led to the increase of austenite and the decrease of hardness in as-cast HHCCI. After heat treatment at 1050 °C, the hardness of HHCCI increased significantly compared with as-cast. And with the increase of Cu content, the hardness of HHCCI increased first and then decreased, and the hardness was the highest when 0.5 wt.% Cu was added. The increase of copper content promotes the precipitation of secondary carbides and makes the interface between α-Fe and M23C6-type secondary carbides a semi-coherent boundary. With the increase of Cu content, the wear loss of HHCCI decreased after heat treatment at 1050 °C, and the wear resistance improved. When the Cu content increased to 1.0 wt.%, the wear resistance of HHCCI was the best, which was 2.6 times that of copper-free HHCCI. The continued increase of copper content has no obvious effect on the wear resistance of HHCCI. In addition, a small amount of Cu tends to adsorb on the (0001) preferential growth surface of M₇C₃-type carbides, thereby refining the carbides. From the First-principles calculations, the solid solution strengthening effect of Cu on the matrix and the adsorption and refinement of carbides were revealed, and the influence mechanism on the wear resistance of HHCCI was characterized.

Keywords: hypereutectic high chromium cast iron, cu alloying, carbides, wear resistance, first-principles calculations

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69 Effect of Molybdenum Addition to Aluminum Grain Refined by Titanium Plus Boron on Its Grain Size and Mechanical Characteristics in the Cast and After Pressing by the Equal Channel Angular Pressing Conditions

Authors: A. I. O. Zaid, A. M. Attieh, S. M. A. Al Qawabah

Abstract:

Aluminum and its alloys solidify in columnar structure with large grain size which tends to reduce their mechanical strength and surface quality. They are, therefore, grain refined by addition of either titanium or titanium plus boron to their melt before solidification. Equal channel angular pressing, ECAP, process is a recent forming method for producing heavy plastic deformation in materials. In this paper, the effect of molybdenum addition to aluminum grain refined by Ti+B on its metallurgical and mechanical characteristics are investigated in the as cast condition and after pressing by the ECAP process. It was found that addition of Mo or Ti+B alone or together to aluminum resulted in grain refining of its microstructure in the as cast condition, as the average grain size was reduced from 139 micron to 46 micron when Mo and Ti+B are added together. Pressing by the ECAP process resulted in further refinement of the microstructure where 32 micron of average grain size was achieved in Al and the Al-Mo microalloy. Regarding the mechanical strength, addition of Mo or Ti+B alone to Al resulted in deterioration of its mechanical behavior but resulted in enhancement of its mechanical behavior when added together, increase of 10% in flow stress was achieved at 20% strain. However, pressing by ECAP addition of Mo or Ti+B alone to Al resulted in enhancement of its mechanical strength but reduced its strength when added together.

Keywords: ECAP, aluminum, cast, mechanical characteristics, Mo grain refiner

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68 Dependence of Free Fatty Acid and Chlorophyll Content on Thermal Stability of Extra Virgin Olive Oil

Authors: Yongjun Ahn, Sung Gyu Choi, Seung-Yeop Kwak

Abstract:

Selective removal of free fatty acid (FFA) and chlorophyll in extra virgin olive oil (EVOO) is necessary to enhance the thermal stability in the condition of the deep frying. In this work, we demonstrated improving the thermal stability of EVOO by selective removal of free fatty acid and chlorophyll using (3-Aminopropyl)trimethoxysilane (APTMS) functionalized mesoporous silica with controlled pore size. The adsorption kinetics of free fatty acid and chlorophyll into the mesoporous silica were quantitatively analyzed by Freundlich and Langmuir model. The highest chlorophyll adsorption efficiency was shown in the pore size at 5 nm, suggesting that the interaction between the silica and the chlorophyll could be optimized at this point. The amino-functionalized mesoporous silica showed drastically improved removal efficiency of FFA than the bare silica. Moreover, beneficial compounds like tocopherol and phenolic compounds maintained even after adsorptive removal. Extra virgin olive oil treated by aminopropyl-functionalized silica had a smoke point high enough to be used as commercial frying oil. Based on these results, it is expected to attract the considerable amount of interest toward facile adsorptive refining process of EVOO using pore size controlled and amino-functionalized mesoporous silica.

Keywords: mesoporous silica, extra virgin olive oil, selective adsorption, thermal stability

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67 Effect of Parenting Style on Aggression and Empathy in Children Between the Age of 10-12

Authors: Debangana Mukherjee

Abstract:

This study delves into the pivotal role of parenting styles in shaping the development of aggression and empathy in children aged 10 to 12. Using a sample of 300 school students, we employed self-assessment questionnaires and scales to investigate correlations between parenting styles—authoritative, authoritarian, permissive, and neglectful—and behavioural traits, focusing on aggression and empathy as primary outcomes. The findings underscore the intricate relationships between parenting styles, aggressive behaviours, and empathetic tendencies. Notably, certain parenting approaches demonstrated strong correlations with specific behavioural outcomes. For instance, authoritarian parenting showed associations with increased aggression and reduced empathy, while authoritative parenting exhibited the opposite trend. These correlations emphasize the potential impact of parenting styles on children's behavioural development during this critical transitional phase. However, this study is limited by its correlational nature, which does not imply causation. The complexities of human behaviour, the limited scope of analysis, and the need for further research into causative relationships and cultural influences call for a nuanced understanding of these dynamics. Moving forward, longitudinal studies, causality investigations, consideration of cultural diversity, and exploration of additional variables could enrich our understanding of the interplay between parenting styles, empathy, and aggression. Validating these findings across diverse populations and refining interventions could pave the way for nurturing healthy behavioural development in children.

Keywords: aggression, correlational nature, empathy, longitudinal studies, parenting style

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66 Cyberfraud Schemes: Modus Operandi, Tools and Techniques and the Role of European Legislation as a Defense Strategy

Authors: Papathanasiou Anastasios, Liontos George, Liagkou Vasiliki, Glavas Euripides

Abstract:

The purpose of this paper is to describe the growing problem of various cyber fraud schemes that exist on the internet and are currently among the most prevalent. The main focus of this paper is to provide a detailed description of the modus operandi, tools, and techniques utilized in four basic typologies of cyber frauds: Business Email Compromise (BEC) attacks, investment fraud, romance scams, and online sales fraud. The paper aims to shed light on the methods employed by cybercriminals in perpetrating these types of fraud, as well as the strategies they use to deceive and victimize individuals and businesses on the internet. Furthermore, this study outlines defense strategies intended to tackle the issue head-on, with a particular emphasis on the crucial role played by European Legislation. European legislation has proactively adapted to the evolving landscape of cyber fraud, striving to enhance cybersecurity awareness, bolster user education, and implement advanced technical controls to mitigate associated risks. The paper evaluates the advantages and innovations brought about by the European Legislation while also acknowledging potential flaws that cybercriminals might exploit. As a result, recommendations for refining the legislation are offered in this study in order to better address this pressing issue.

Keywords: business email compromise, cybercrime, European legislation, investment fraud, NIS, online sales fraud, romance scams

Procedia PDF Downloads 57
65 Effect of Parenting Style on Aggression and Empathy in Children Between the Ages of 10-12

Authors: Debangana Mukherjee

Abstract:

This study delves into the pivotal role of parenting styles in shaping the development of aggression and empathy in children aged 10 to 12. Using a sample of 300 school students, we employed self-assessment questionnaires and scales to investigate correlations between parenting styles—authoritative, authoritarian, permissive, and neglectful—and behavioural traits, focusing on aggression and empathy as primary outcomes. The findings underscore the intricate relationships between parenting styles, aggressive behaviours, and empathetic tendencies. Notably, certain parenting approaches demonstrated strong correlations with specific behavioural outcomes. For instance, authoritarian parenting showed associations with increased aggression and reduced empathy, while authoritative parenting exhibited the opposite trend. These correlations emphasize the potential impact of parenting styles on children's behavioural development during this critical transitional phase. However, this study is limited by its correlational nature, which does not imply causation. The complexities of human behaviour, the limited scope of analysis, and the need for further research into causative relationships and cultural influences call for a nuanced understanding of these dynamics. Moving forward, longitudinal studies, causality investigations, consideration of cultural diversity, and exploration of additional variables could enrich our understanding of the interplay between parenting styles, empathy, and aggression. Validating these findings across diverse populations and refining interventions could pave the way for nurturing healthy behavioural development in children.

Keywords: aggression, correlational nature, empathy, longitudinal studies, parenting style

Procedia PDF Downloads 28
64 Visual Speech Perception of Arabic Emphatics

Authors: Maha Saliba Foster

Abstract:

Speech perception has been recognized as a bi-sensory process involving the auditory and visual channels. Compared to the auditory modality, the contribution of the visual signal to speech perception is not very well understood. Studying how the visual modality affects speech recognition can have pedagogical implications in second language learning, as well as clinical application in speech therapy. The current investigation explores the potential effect of speech visual cues on the perception of Arabic emphatics (AEs). The corpus consists of 36 minimal pairs each containing two contrasting consonants, an AE versus a non-emphatic (NE). Movies of four Lebanese speakers were edited to allow perceivers to have partial view of facial regions: lips only, lips-cheeks, lips-chin, lips-cheeks-chin, lips-cheeks-chin-neck. In the absence of any auditory information and relying solely on visual speech, perceivers were above chance at correctly identifying AEs or NEs across vowel contexts; moreover, the models were able to predict the probability of perceivers’ accuracy in identifying some of the COIs produced by certain speakers; additionally, results showed an overlap between the measurements selected by the computer and those selected by human perceivers. The lack of significant face effect on the perception of AEs seems to point to the lips, present in all of the videos, as the most important and often sufficient facial feature for emphasis recognition. Future investigations will aim at refining the analyses of visual cues used by perceivers by using Principal Component Analysis and including time evolution of facial feature measurements.

Keywords: Arabic emphatics, machine learning, speech perception, visual speech perception

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63 Hydrodynamic Modeling of the Hydraulic Threshold El Haouareb

Authors: Sebai Amal, Massuel Sylvain

Abstract:

Groundwater is the key element of the development of most of the semi-arid areas where water resources are increasingly scarce due to an irregularity of precipitation, on the one hand, and an increasing demand on the other hand. This is the case of the watershed of the Central Tunisia Merguellil, object of the present study, which focuses on an implementation of an underground flows hydrodynamic model to understand the recharge processes of the Kairouan’s plain groundwater by aquifers boundary through the hydraulic threshold of El Haouareb. The construction of a conceptual geological 3D model by the Hydro GeoBuilder software has led to a definition of the aquifers geometry in the studied area thanks to the data acquired by the analysis of geologic sections of drilling and piezometers crossed shells partially or in full. Overall analyses of the piezometric Chronicles of different piezometers located at the level of the dam indicate that the influence of the dam is felt especially in the aquifer carbonate which confirms that the dynamics of this aquifer are highly correlated to the dam’s dynamic. Groundwater maps, high and low-water dam, show a flow that moves towards the threshold of El Haouareb to the discharge of the waters of Ain El Beidha discharge towards the plain of Kairouan. Software FEFLOW 5.2 steady hydrodynamic modeling to simulate the hydraulic threshold at the level of the dam El Haouareb in a satisfactory manner. However, the sensitivity study to the different parameters shows equivalence problems and a fix to calibrate the limestones’ permeability. This work could be improved by refining the timing steady and amending the representation of limestones in the model.

Keywords: Hydrodynamic modeling, lithological modeling, hydraulic, semi-arid, merguellil, central Tunisia

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62 Environment and Social Management Strategy at Kuwait Integrated Petroleum Industries Company

Authors: Hannan Al-Qanai, Haitham Mustafa, Rajeswaran Sivasankar

Abstract:

Kuwait Integrated Petroleum Industries Company (KIPIC, Company), established in 2016 as a subsidiary to Kuwait Petroleum Corporation (KPC), is responsible for operating and managing the largest grassroots integrated complex for refining, petrochemicals manufacture businesses, and liquefied natural gas import facilities at Al-Zour, Kuwait. KIPIC and its Contractors/sub-contractors employ over 69,000 staff in its current projects at Al-Zour during peak construction activity. KIPIC holds a unique responsibility to the society, which includes all stakeholders, and demonstrates its social commitment in developing an integrated environment & social management system (ESMS) and ensuring sustainability. This paper mainly demonstrates the knowledge on corporate branding from a corporate social responsibility (CSR) perspective and presents the achievements and best practices of KIPIC in the field of CSR and the challenges faced in handling social issues. Moreover, the study is based on qualitative data abstracted from KIPIC Health, Safety, Security & Environment Management System (HSSE MS) procedures, audit reports, the outcome of counseling sessions, national and international laws and regulations, and International Guidelines on Environment and Social Management System (ESMS). KIPIC has committed to caring for the environmental concerns and acting on social as they do on profits and economic growth. The main findings of this paper are that the successful implementation and operationalization of CSR within an organization depends on a simple but stringent process with both top-down and bottom-up commitment.

Keywords: welfare, corporate social responsibility, social management, sustainability

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61 From Plate to Self-Perception: Unravelling the Interplay Between Food Security and Self-Esteem Among Malaysian University Students

Authors: Amiraa Ali Mansor, Haslinda Abdullah, Angela Chan Nguk Fong, Norhaida Hanim Binti Ahmad Tajudin, Asnarulkhadi Abu Samah

Abstract:

Obesity has risen sharply over the past three decades, posing a grave public health concern globally. In Malaysia, it has also emerged as a significant health threat. While the second Sustainable Development Goal, "Zero Hunger", aims to ensure equitable access to nutritious food for all, a key challenge lies in addressing food insecurity. Food insecurity not only pertains to the quantity but also the quality of food, with both dimensions playing a pivotal role in health outcomes. To date, much of the research on food security has focused on household levels. There remains a research gap concerning university students, a population transitioning to independence from parental support and grappling with limited resources. This study seeks to bridge this gap by extending the Food Security Theory to incorporate the psychological dimension of self-esteem. Using a quantitative approach, data was collected from 452 public university students in Malaysia through a cross-sectional research design and a multi-stage cluster sampling technique. The anticipated findings will provide novel insights by linking food security with self-esteem. Such insights have implications for healthcare policy and the framing of preventive strategies against obesity. It is hoped that this research will not only contribute to the academic discourse on Food Security Theory but also serve as a foundation for refining national health policies and programs aimed at fostering a healthier lifestyle.

Keywords: obesity, food security, body image, self-esteem

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60 Towards Renewable Energy: A Qualitative Study of Biofuel Development Policy in Indonesia

Authors: Arie Yanwar Kapriadi

Abstract:

This research is aiming to develop deeper understanding of the scale of power that shaped the biofuel policy. This research is important for the following reasons. Firstly, this research will enrich the body of literature within the field of political ecology, scale and environmental governance. Secondly, by focussing on energy transition policies, this research offers a critical perspective on how government policy, aimed at delivering low carbon sustainable energy systems, being scaled and implemented through multi variate stakeholders. Finally, the research could help the government of Indonesia as a policy evaluation on delivering low carbon sustainable energy systems at the macro level that (possibility) being unable to be delivered at different scale and instead being perceived differently by different stakeholders. Qualitative method is applied particularly an in depth interview with government officials as well as policy stakeholders outside of government and people in positions of responsibility with regards to policy delivery. There are 4 field study location where interview took place as well as sites visit to some biofuel refining facilities. There are some major companies which involve on the production and distribution of biofuel and its relation with biofuel feedstock industry as the source of data. The research investigates how the government biofuel policies correlated with other policy issues such as land reclassification and carbon emission reduction which also influenced plantations expansion as well as its impact on the local people. The preliminary result shows tension of power between governing authorities caused the Indonesian biofuel policy being unfocused which led to failing to meet its mandatory blending target despite the abundance of its feedstock.

Keywords: biofuel, energy transition, renewable energy, political ecology

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59 Review of Sulfur Unit Capacity Expansion Options

Authors: Avinashkumar Karre

Abstract:

Sulfur recovery unit, most commonly called as Claus process, is very significant gas desulfurization process unit in refinery and gas industries. Explorations of new natural gas fields, refining of high-sulfur crude oils, and recent crude expansion projects are needing capacity expansion of Claus unit for many companies around the world. In refineries, the sulphur recovery units take acid gas from amine regeneration units and sour water strippers, converting hydrogen sulfide to elemental sulfur using the Claus process. The Claus process is hydraulically limited by mass flow rate. Reducing the pressure drop across control valves, flow meters, lines, knock-out drums, and packing improves the capacity. Oxygen enrichment helps improve the capacity by removing nitrogen, this is more commonly done on all capacity expansion projects. Typical upgrades required due to oxygen enrichment are new burners, new refractory in thermal reactor, resizing of 1st condenser, instrumentation changes, and steam/condensate heat integration. Some other capacity expansion options typically considered are tail gas compressor, replacing air blower with higher head, hydrocarbon minimization in the feed, water removal, and ammonia removal. Increased capacity related upgrades in sulfur recovery unit also need changes in the tail gas treatment unit, typical changes include improvement to quench tower duty, packing area upgrades in quench and absorber towers and increased amine circulation flow rates.

Keywords: Claus process, oxygen enrichment, sulfur recovery unit, tail gas treatment unit

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58 Evaluation of Immunology of Asthma Chronic Obstructive

Authors: Milad Gholizadeh

Abstract:

Asthma and chronic obstructive pulmonary disease (COPD) are very shared inflammatory diseases of the airlines. They togethercause airway tapering and are cumulative in occurrence throughout the world, imposing huge burdens on health care. It is currently recognized that some asthmatic inflammation is neutrophilic, controlled by the TH17 subset of helper T cells, and that some eosinophilic inflammation is controlled by type 2 innate lymphoid cells (ILC2 cells) temporary together with basophils. Patients who have plain asthma or are asthmatic patients who smoke with topographies of COPD-induced inflammation and might advantage from treatments targeting neutrophils, countingmacrolides, CXCR2 antagonists, phosphodiesterase 4 inhibitors, p38 mitogen-activating protein kinase inhibitors, and antibodies in contradiction of IL-1 and IL-17.Viral and bacterial infections, not only reason acute exacerbations of COPD, but also intensify and continue chronic inflammation in steady COPD through pathogen-associated molecular patterns. Present treatment plans are absorbed on titration of inhaled therapies such as long-acting bronchodilators, with cumulative interest in the usage of beleaguered biologic therapies meant at the underlying inflammatory devices. Educationssuggest that the mucosal IgA reply is abridged in COPD, and a lacking conveyance of IgA across the bronchial epithelium in COPD has been recognized, perhaps involving neutrophil proteinases, which may damage the Ig receptor mediating this transepithelialdirection-finding. Future instructions for investigation will emphasis elucidating the diverse inflammatory signatures foremost to asthma and chronic obstrucive, the development of reliable analytic standards and biomarkers of illness, and refining the clinical organization with an eye toward targeted therapies.

Keywords: imminology, asthma, COPD, CXCR2 antagonists

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57 The Optimization of the Parameters for Eco-Friendly Leaching of Precious Metals from Waste Catalyst

Authors: Silindile Gumede, Amir Hossein Mohammadi, Mbuyu Germain Ntunka

Abstract:

Goal 12 of the 17 Sustainable Development Goals (SDGs) encourages sustainable consumption and production patterns. This necessitates achieving the environmentally safe management of chemicals and all wastes throughout their life cycle and the proper disposal of pollutants and toxic waste. Fluid catalytic cracking (FCC) catalysts are widely used in the refinery to convert heavy feedstocks to lighter ones. During the refining processes, the catalysts are deactivated and discarded as hazardous toxic solid waste. Spent catalysts (SC) contain high-cost metal, and the recovery of metals from SCs is a tactical plan for supplying part of the demand for these substances and minimizing the environmental impacts. Leaching followed by solvent extraction, has been found to be the most efficient method to recover valuable metals with high purity from spent catalysts. However, the use of inorganic acids during the leaching process causes a secondary environmental issue. Therefore, it is necessary to explore other alternative efficient leaching agents that are economical and environmentally friendly. In this study, the waste catalyst was collected from a domestic refinery and was characterised using XRD, ICP, XRF, and SEM. Response surface methodology (RSM) and Box Behnken design were used to model and optimize the influence of some parameters affecting the acidic leaching process. The parameters selected in this investigation were the acid concentration, temperature, and leaching time. From the characterisation results, it was found that the spent catalyst consists of high concentrations of Vanadium (V) and Nickel (Ni); hence this study focuses on the leaching of Ni and V using a biodegradable acid to eliminate the formation of the secondary pollution.

Keywords: eco-friendly leaching, optimization, metal recovery, leaching

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56 Experimental and Numerical Evaluation of a Shaft Failure Behaviour Using Three-Point Bending Test

Authors: Bernd Engel, Sara Salman Hassan Al-Maeeni

Abstract:

A substantial amount of natural resources are nowadays consumed at a growing rate, as humans all over the world used materials obtained from the Earth. Machinery manufacturing industry is one of the major resource consumers on a global scale. Even though the incessant finding out of the new material, metals, and resources, it is urgent for the industry to develop methods to use the Earth's resources intelligently and more sustainable than before. Re-engineering of machine tools regarding design and failure analysis is an approach whereby out-of-date machines are upgraded and returned to useful life. To ensure the reliable future performance of the used machine components, it is essential to investigate the machine component failure through the material, design, and surface examinations. This paper presents an experimental approach aimed at inspecting the shaft of the rotary draw bending machine as a case to study. The testing methodology, which is based on the principle of the three-point bending test, allows assessing the shaft elastic behavior under loading. Furthermore, the shaft elastic characteristics include the maximum linear deflection, and maximum bending stress was determined by using an analytical approach and finite element (FE) analysis approach. In the end, the results were compared with the ones obtained by the experimental approach. In conclusion, it is seen that the measured bending deflection and bending stress were well close to the permissible design value. Therefore, the shaft can work in the second life cycle. However, based on previous surface tests conducted, the shaft needs surface treatments include re-carburizing and refining processes to ensure the reliable surface performance.

Keywords: deflection, FE analysis, shaft, stress, three-point bending

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55 The Role of Fluid Catalytic Cracking in Process Optimisation for Petroleum Refineries

Authors: Chinwendu R. Nnabalu, Gioia Falcone, Imma Bortone

Abstract:

Petroleum refining is a chemical process in which the raw material (crude oil) is converted to finished commercial products for end users. The fluid catalytic cracking (FCC) unit is a key asset in refineries, requiring optimised processes in the context of engineering design. Following the first stage of separation of crude oil in a distillation tower, an additional 40 per cent quantity is attainable in the gasoline pool with further conversion of the downgraded product of crude oil (residue from the distillation tower) using a catalyst in the FCC process. Effective removal of sulphur oxides, nitrogen oxides, carbon and heavy metals from FCC gasoline requires greater separation efficiency and involves an enormous environmental significance. The FCC unit is primarily a reactor and regeneration system which employs cyclone systems for separation.  Catalyst losses in FCC cyclones lead to high particulate matter emission on the regenerator side and fines carryover into the product on the reactor side. This paper aims at demonstrating the importance of FCC unit design criteria in terms of technical performance and compliance with environmental legislation. A systematic review of state-of-the-art FCC technology was carried out, identifying its key technical challenges and sources of emissions.  Case studies of petroleum refineries in Nigeria were assessed against selected global case studies. The review highlights the need for further modelling investigations to help improve FCC design to more effectively meet product specification requirements while complying with stricter environmental legislation.

Keywords: design, emission, fluid catalytic cracking, petroleum refineries

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54 Effectiveness of Management Transfer Programs for Managing Irrigation Resources in Developing Countries: A Case Study of Farmer- and Agency-Managed Schemes from Nepal

Authors: Tirtha Raj Dhakal, Brian Davidson, Bob Farquharson

Abstract:

Irrigation management transfer has been taken as the important policy instrument for effective irrigation resource management in many developing countries. The change in governance of the irrigation schemes for its day-to-day operation and maintenance has been centered in recent Nepalese irrigation policies also. However, both farmer- and agency-managed irrigation schemes in Nepal are performing well below than expected. This study tries to link the present concerns of poor performance of both forms of schemes with the institutions for its operation and management. Two types of surveys, management and farm surveys; were conducted as a case study in the command area of Narayani Lift Irrigation Project (agency-managed) and Khageri Irrigation System (farmer-managed) of Chitwan District. The farm survey from head, middle and tail regions of both schemes revealed that unequal water distribution exists in these regions in both schemes with greater percentage of farmers experiencing this situation in agency managed scheme. In both schemes, the cost recovery rate was very low, even below five percent in Lift System indicating poor operation and maintenance of the schemes. Also, the institution on practice in both schemes is unable to create any incentives for farmers’ willingness to pay as well as for its economical use in the farm. Thus, outcomes from the study showed that only the management transfer programs may not achieve the goal of efficient irrigation resource management. This may suggest water professionals to rethink about the irrigation policies for refining institutional framework irrespective of the governance of schemes for improved cost recovery and better water distribution throughout the irrigation schemes.

Keywords: cost recovery, governance, institution, irrigation management transfer, willingness to pay

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53 Sonodynamic Activity of Porphyrins-SWCNT

Authors: F. Bosca, F. Foglietta, F. Turci, E. Calcio Gaudino, S. Mana, F. Dosio, R. Canaparo, L. Serpe, A. Barge

Abstract:

In recent years, medical science has improved chemotherapy, radiation therapy and adjuvant therapy and has developed newer targeted therapies as well as refining surgical techniques for removing cancer. However, the chances of surviving the disease depend greatly on the type and location of the cancer and the extent of the disease at the start of treatment. Moreover, mainstream forms of cancer treatment have side effects which range from the unpleasant to the fatal. Therefore, the continuation of progress in anti-cancer therapy may depend on placing emphasis on other existing but less thoroughly investigated therapeutic approaches such as Sonodynamic Therapy (SDT). SDT is based on the local activation of a so called 'sonosensitizer', a molecule able to be excited by ultrasound, the radical production as a consequence of its relaxation processes and cell death due to different mechanisms induced by radical production. The present work deals with synthesis, characterization and preliminary in vitro test of Single Walled Carbon Nanotubes (SWCNT) decorated with porphyrins and biological vectors. The SWCNT’s surface was modified exploiting 1, 3-dipolar cycloaddition or Dies Alder reactions. For this purpose, different porphyrins scaffolds were ad-hoc synthesized using also non-conventional techniques. To increase cellular specificity of porphyrin-conjugated SWCNTs and to improve their ability to be suspended in aqueous solution, the modified nano-tubes were grafted with suitable glutamine or hyaluronic acid derivatives. These nano-sized sonosensitizers were characterized by several methodologies and tested in vitro on different cancer cell lines.

Keywords: sonodynamic therapy, porphyrins synthesis and modification, SWNCT grafting, hyaluronic acid, anti-cancer treatment

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52 Assessment of Air Quality Around Western Refinery in Libya: Mobile Monitoring

Authors: A. Elmethnani, A. Jroud

Abstract:

This coastal crude oil refinery is situated north of a big city west of Tripoli; the city then could be highly prone to downwind refinery emissions where the NNE wind direction is prevailing through most seasons of the year. Furthermore, due to the absence of an air quality monitoring network and scarce emission data available for the neighboring community, nearby residents have serious worries about the impacts of the oil refining operations on local air quality. In responding to these concerns, a short term survey has performed for three consecutive days where a semi-continues mobile monitoring approach has developed effectively in this study; the monitoring station (Compact AQM 65 AeroQual) was mounted on a vehicle to move quickly between locations, measurements of 10 minutes averaging of 60 seconds then been taken at each fixed sampling point. The downwind ambient concentration of CO, H₂S, NOₓ, NO₂, SO₂, PM₁, PM₂.₅ PM₁₀, and TSP were measured at carefully chosen sampling locations, ranging from 200m nearby the fence-line passing through the city center up to 4.7 km east to attain best spatial coverage. Results showed worrying levels of PM₂.₅ PM₁₀, and TSP at one sampling location in the city center, southeast of the refinery site, with an average mean of 16.395μg/m³, 33.021μg/m³, and 42.426μg/m³ respectively, which could be attributed to road traffic. No significant concentrations have been detected for other pollutants of interest over the study area, as levels observed for CO, SO₂, H₂S, NOₓ, and NO₂ haven’t respectively exceeded 1.707 ppm, 0.021ppm, 0.134 ppm, 0.4582 ppm, and 0.0018 ppm, which was at the same sampling locations as well. Although it wasn’t possible to compare the results with the Libyan air quality standards due to the difference in the averaging time period, the technique was adequate for the baseline air quality screening procedure. Overall, findings primarily suggest modeling of dispersion of the refinery emissions to assess the likely impact and spatial-temporal distribution of air pollutants.

Keywords: air quality, mobil monitoring, oil refinery

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51 From Mobility to Complexity: French Language Use among Algerian Doctoral Postgraduates in Scotland

Authors: Hadjer Chellia

Abstract:

The study explores the phenomenon of second language use in a migratory setting and uses the case of Algerian international students in Scotland, United Kingdom. The linguistic history of Algeria reveals that French language has a high status among the Algerians’ verbal repertoires and Algerian English students consider it as a language of prestige. With mobility of some of these students towards Scotland -in the guise of internationalization of higher education, mobility and exchange programs, the transition was deemed to bring more complexity to their pre-migratory linguistic repertoires and resulted into their French language- being endangered and threatened by a potential shift to English. The study employed semi-structured interviews among six Ph.D. ethnically related students, and the main aim behind that is to explore their current experiences with regards to French language use and to provide an account of the factors which assist in shifting to English as a second language instead. The six participants identified in interviews were further invited to focus group sessions based on an in-group interaction fashion to discuss different topics using heritage languages. This latter was opted for as part of the methodology as a means to observe their real linguistic practice and to investigate the link between behaviors and previous perceptions. The findings detect a variety of social, individual and socio-psychological factors that would contribute in refining the concept of language shift among newly established émigré communities with short stay vis a vis the linguistic outcomes of immigrants with long stay, across generational basis that was –to some extent-the focus of previous research on language shift. The results further reveal a mismatch between students' perceptions and observed behaviors. The research is then largely relevant to international students’ sociolinguistic experience of study abroad.

Keywords: complexity, mobility, potential shift, sociolinguistic experience

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50 Towards a Robust Patch Based Multi-View Stereo Technique for Textureless and Occluded 3D Reconstruction

Authors: Ben Haines, Li Bai

Abstract:

Patch based reconstruction methods have been and still are one of the top performing approaches to 3D reconstruction to date. Their local approach to refining the position and orientation of a patch, free of global minimisation and independent of surface smoothness, make patch based methods extremely powerful in recovering fine grained detail of an objects surface. However, patch based approaches still fail to faithfully reconstruct textureless or highly occluded surface regions thus though performing well under lab conditions, deteriorate in industrial or real world situations. They are also computationally expensive. Current patch based methods generate point clouds with holes in texturesless or occluded regions that require expensive energy minimisation techniques to fill and interpolate a high fidelity reconstruction. Such shortcomings hinder the adaptation of the methods for industrial applications where object surfaces are often highly textureless and the speed of reconstruction is an important factor. This paper presents on-going work towards a multi-resolution approach to address the problems, utilizing particle swarm optimisation to reconstruct high fidelity geometry, and increasing robustness to textureless features through an adapted approach to the normalised cross correlation. The work also aims to speed up the reconstruction using advances in GPU technologies and remove the need for costly initialization and expansion. Through the combination of these enhancements, it is the intention of this work to create denser patch clouds even in textureless regions within a reasonable time. Initial results show the potential of such an approach to construct denser point clouds with a comparable accuracy to that of the current top-performing algorithms.

Keywords: 3D reconstruction, multiview stereo, particle swarm optimisation, photo consistency

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49 The Effects of Water Fraction and Salinity on Crude Oil-Water Dispersions

Authors: Ramin Dabirian, Yi Zhang, Ilias Gavrielatos, Ram Mohan, Ovadia Shoham

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Oil-water emulsions can be found in almost every part of the petroleum industry, namely in reservoir rocks, drilling cuttings circulation, production in wells, transportation pipelines, surface facilities and refining process. However, it is necessary for oil production and refinery engineers to resolve the petroleum emulsion problems as well as to eliminate the contaminants in order to meet environmental standards, achieve the desired product quality and to improve equipment reliability and efficiency. A state-of-art Dispersion Characterization Rig (DCR) has been utilized to investigate crude oil-distilled water dispersion separation. Over 80 experimental tests were ran to investigate the flow behavior and stability of the dispersions. The experimental conditions include the effects of water cuts (25%, 50% and 75%), NaCl concentrations (0, 3.5% and 18%), mixture flow velocities (0.89 and 1.71 ft/s), and also orifice place types on the separation rate. The experimental data demonstrate that the water cut can significantly affects the separation time and efficiency. The dispersion with lower water cut takes longer time to separate and have low separation efficiency. The medium and lower water cuts will result in the formation of Mousse emulsion and the phase inversion happens around the medium water cut. The data also confirm that increasing the NaCl concentration in aqueous phase can increase the crude oil water dispersion separation efficiency especially at higher salinities. The separation profile for dispersions with lower salt concentrations has a lower sedimentation rate slope before the inflection point. Dispersions in all tests with higher salt concentrations have a larger sedimenting rate. The presence of NaCl can influence the interfacial tension gradients along the interface and it plays a role in avoiding the Mousse emulsion formation.

Keywords: oil-water dispersion, separation mechanism, phase inversion, emulsion formation

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48 Wear Progress and -Mechanisms in Torpedo Ladles in Steel Industry

Authors: Mattahias Maj, Fabio Tatzgern, Karl Adam, Damir Kahrimanovic, Markus Varga

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Torpedo ladles are necessary transport carriages in steel production to move the molten crude iron from the blast furnace to the steel refining plant. This requires the ladles to be high temperature resistant and insulate well to preserve the temperature and hold the risk of solidification at bay. Therefore, the involved refractories lining the inside of the torpedo ladles are chosen mostly according to their thermal properties, although wear of the materials by the liquid iron is also of major importance. In this work, we combined investigations of the thermal behaviour with wear studies of the lining over the whole lifetime of a torpedo ladle. Additional numerical simulations enabled a detailed model of the mechanical loads and temperature propagation at the various stations (heating, filling, emptying, cooling). The core of the investigation were detailed 3D measurements of the ladle’s cavity and thereby quantitative information of the wear progress at different time intervals during the lifetime of the ladles. The measurements allowed for a separation of different wear zones according to severity, namely the “splash zone” where the melt directly hits the ladle, the “melt zone” where during transport always liquid melt is present, and the “slag zone”, where the slag floats on the melt causing the most severe wear loss. Numerical simulations of the filling process were taken to calculate stress levels and temperature gradients, which led to the different onset of wear on those zones. Thermal imaging and punctual temperature measurements allowed for a study of the thermal consequences entailed by the wear onset. Additional “classical” damage analysis of the worn refractories complete the investigation. Thereby the wear mechanisms leading to the substantial wear loss were disclosed.

Keywords: high temperature, tribology, liquid-solid interaction, refractories, thermography

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47 Elucidating Microstructural Evolution Mechanisms in Tungsten via Layerwise Rolling in Additive Manufacturing: An Integrated Simulation and Experimental Approach

Authors: Sadman Durlov, Aditya Ganesh-Ram, Hamidreza Hekmatjou, Md Najmus Salehin, Nora Shayesteh Ameri

Abstract:

In the field of additive manufacturing, tungsten stands out for its exceptional resistance to high temperatures, making it an ideal candidate for use in extreme conditions. However, its inherent brittleness and vulnerability to thermal cracking pose significant challenges to its manufacturability. This study explores the microstructural evolution of tungsten processed through layer-wise rolling in laser powder bed fusion additive manufacturing, utilizing a comprehensive approach that combines advanced simulation techniques with empirical research. We aim to uncover the complex processes of plastic deformation and microstructural transformations, with a particular focus on the dynamics of grain size, boundary evolution, and phase distribution. Our methodology employs a combination of simulation and experimental data, allowing for a detailed comparison that elucidates the key mechanisms influencing microstructural alterations during the rolling process. This approach facilitates a deeper understanding of the material's behavior under additive manufacturing conditions, specifically in terms of deformation and recrystallization. The insights derived from this research not only deepen our theoretical knowledge but also provide actionable strategies for refining manufacturing parameters to improve the tungsten components' mechanical properties and functional performance. By integrating simulation with practical experimentation, this study significantly enhances the field of materials science, offering a robust framework for the development of durable materials suited for challenging operational environments. Our findings pave the way for optimizing additive manufacturing techniques and expanding the use of tungsten across various demanding sectors.

Keywords: additive manufacturing, layer wise rolling, refractory materials, in-situ microstructure modifications

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46 Synthesis and Gas Transport Properties of Polynorbornene Dicarboximides Bearing Trifluoromethyl Isomer Moieties

Authors: Jorge A. Cruz-Morales, Joel Vargas, Arlette A. Santiago, Mikhail A. Tlenkopatchev

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In industrial processes such as oil extraction and refining, products are handled or generated in the gas phase, which represents a challenge in terms of treatment and purification. During the past three decades, new scientific findings and technological advances in separation based on the use of membranes have led to simpler and more efficient gas separation processes, optimizing the use of energy and generating less pollution. This work reports the synthesis and ring-opening metathesis polymerization (ROMP) of new structural isomers based on norbornene dicarboximides bearing trifluoromethyl moieties, specifically N-2-trifluoromethylphenyl-exo,endo-norbornene-5,6-dicarboximide (2a) and N-3-trifluoromethylphenyl-exo,endo-norbornene-5,6-dicarboximide (2b), using tricyclohexylphosphine [1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene][benzylidene] ruthenium dichloride (I), bis(tricyclohexylphosphine) benzylidene ruthenium (IV) dichloride (II), and bis(tricyclohexylphosphine) p-fluorophenylvinylidene ruthenium (II) dichloride (III). It was observed that the -CF3 moiety attached at the ortho position of the aromatic ring increases thermal and mechanical properties of the polymer, whereas meta substitution has the opposite effect. A comparative study of gas transportation in membranes, based on these fluorinated polynorbornenes, showed that -CF3 ortho substitution increases permeability of the polymer membrane as a consequence of the increase in both gas solubility and gas diffusion. In contrast, gas permeability coefficients of the meta-substituted polymer membrane are rather similar to those of that which is non-fluorinated; this can be attributed to a lower fractional free volume. The meta-substituted polymer membrane, besides showing the largest permselectivity coefficients of all the isomers studied here, was also found to have one of the largest permselectivity coefficients for separating H2/C3H6 into glassy polynorbornene dicarboximides.

Keywords: gas transport membranes, polynorbornene dicarboximide, ROMP, structural isomers

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45 Digital Governance Decision-Making in the Aftermath of Cybersecurity Crises, Lessons from Estonia

Authors: Logan Carmichael

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As the world’s governments seek to increasingly digitize their service provisions, there exists a subsequent and fully valid concern about the security underpinning these digital governance provisions. Estonia, a small and innovative Baltic nation, has been refining both its digital governance structure and cybersecurity mechanisms for over three decades and has been praised as global ‘best practice’ in both fields. However, the security of the Estonian digital governance system has been ever-evolving and significantly shaped by cybersecurity crises. This paper examines said crises – 2007 cyberattacks on Estonian government, banks, and news media; the 2017 e-ID crisis; the ongoing COVID-19 pandemic; and the 2022 Russian invasion of Ukraine – and how governance decision-making following these crises has shaped the cybersecurity of the digital governance structure in Estonia. This paper employs a blended constructivist and historical institutionalist theoretical approach as a useful means to view governance and decision-making in the wake of cybersecurity incidents affecting the Estonian digital governance structure. Together, these theoretical groundings frame the topics of cybersecurity and digital governance in an Estonian context through a lens of ideation and experience, as well as institutional path dependencies over time and cybersecurity crises as critical junctures to study. Furthermore, this paper takes a qualitative approach, employing discourse analysis, policy analysis, and elite interviewing of Estonian officials involved in digital governance and cybersecurity in order to glean nuanced perspectives into the processes that followed these four crises. Ultimately, the results of this paper will offer insight into how governments undertake policy-driven change following cybersecurity crises to ensure sufficient security of their digitized service provisions. This paper’s findings are informative not only in continued decision-making in the Estonian system but also in other states currently implementing a digital governance structure, for which security mechanisms are of the utmost importance.

Keywords: cybersecurity, digital governance, Estonia, crisis management, governance in crisis

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44 Utilization of Pozzolonic Material for the Enhancement of the Concrete Strength: A Comprehensive Review Paper

Authors: M. Parvez Alam, M. Bilal Khan

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Concrete is the material of choice where strength, performance, durability, impermeability, fire resistance, and abrasion resistance are required. The hunger for the higher strength leads to other materials to achieve the desired results and thus, emerged the contribution of cementitious material for the strength of concrete In present day constructions, concrete is chosen as one of the best choices by civil engineers in construction materials. The concept of sustainability is touching new heights and many pozzolonic materials are tried and tested as partial replacement for the cement. In this paper, comprehensive review of available literatures are studied to evaluate the performance of pozzolonic materials such as ceramic waste powder, copper slag, silica fume on the strength of concrete by the partial replacement of ordinary materials such as cement, fine aggregate and coarse aggregate at different percentage of composition. From the study, we conclude that ceramic wastes are suitable to be used in the construction industry, and more significantly on the making of concrete. Ceramic wastes are found to be suitable for usage as substitution for fine and coarse aggregates and partial substitution in cement production. They were found to be performing better than normal concrete, in properties such as density, durability, permeability, and compressive strength. Copper slag is the waste material of matte smelting and refining of copper such that each ton of copper generates approximately 2.5 tons of copper slag. Copper slag is one of the materials that is considered as a waste which could have a promising future in construction Industry as partial or full substitute of aggregates. Silica fume, also known as micro silica or condensed silica fume, is a relatively new material compared to fly ash, It is another material that is used as an artificial pozzolonic admixture. High strength concrete made with silica fume provides high abrasion/corrosion resistance.

Keywords: concrete, pozzolonic materials, ceramic waste powder, copper slag

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43 In vitro Evaluation of Prebiotic Potential of Wheat Germ

Authors: Lígia Pimentel, Miguel Pereira, Manuela Pintado

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Wheat germ is a by-product of wheat flour refining. Despite this by-product being a source of proteins, lipids, fibres and complex carbohydrates, and consequently a valuable ingredient to be used in Food Industry, only few applications have been studied. The main goal of this study was to assess the potential prebiotic effect of natural wheat germ. The prebiotic potential was evaluated by in vitro assays with individual microbial strains (Lactobacillus paracasei L26 and Lactobacillus casei L431). A simulated model of the gastrointestinal digestion was also used including the conditions present in the mouth (artificial saliva), oesophagus–stomach (artificial gastric juice), duodenum (artificial intestinal juice) and ileum. The effect of natural wheat germ and wheat germ after digestion on the growth of lactic acid bacteria was studied by growing those microorganisms in de Man, Rogosa and Sharpe (MRS) broth (with 2% wheat germ and 1% wheat germ after digestion) and incubating at 37 ºC for 48 h with stirring. A negative control consisting of MRS broth without glucose was used and the substrate was also compared to a commercial prebiotic fructooligosaccharides (FOS). Samples were taken at 0, 3, 6, 9, 12, 24 and 48 h for bacterial cell counts (CFU/mL) and pH measurement. Results obtained showed that wheat germ has a stimulatory effect on the bacteria tested, presenting similar (or even higher) results to FOS, when comparing to the culture medium without glucose. This was demonstrated by the viable cell counts and also by the decrease on the medium pH. Both L. paracasei L26 and L. casei L431 could use these compounds as a substitute for glucose with an enhancement of growth. In conclusion, we have shown that wheat germ stimulate the growth of probiotic lactic acid bacteria. In order to understand if the composition of gut bacteria is altered and if wheat germ could be used as potential prebiotic, further studies including faecal fermentations should be carried out. Nevertheless, wheat germ seems to have potential to be a valuable compound to be used in Food Industry, mainly in the Bakery Industry.

Keywords: by-products, functional ingredients, prebiotic potential, wheat germ

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42 Recycling of Spent Mo-Co Catalyst for the Recovery of Molybdenum Using Cyphos IL 104

Authors: Harshit Mahandra, Rashmi Singh, Bina Gupta

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Molybdenum is widely used in thermocouples, anticathode of X-ray tubes and in the production of alloys of steels. Molybdenum compounds are extensively used as a catalyst in petroleum-refining industries for hydrodesulphurization. Activity of the catalysts decreases gradually with time and are dumped as hazardous waste due to contamination with toxic materials during the process. These spent catalysts can serve as a secondary source for metal recovery and help to sort out environmental and economical issues. In present study, extraction and separation of molybdenum from a Mo-Co spent catalyst leach liquor containing 0.870 g L⁻¹ Mo, 0.341 g L⁻¹ Co, 0.422 ×10⁻¹ g L⁻¹ Fe and 0.508 g L⁻¹ Al in 3 mol L⁻¹ HCl has been investigated using solvent extraction technique. The extracted molybdenum has been finally recovered as molybdenum trioxide. Leaching conditions used were- 3 mol L⁻¹ HCl, 90°C temperature, solid to liquid ratio (w/v) of 1.25% and reaction time of 60 minutes. 96.45% molybdenum was leached under these conditions. For the extraction of molybdenum from leach liquor, Cyphos IL 104 [trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate] in toluene was used as an extractant. Around 91% molybdenum was extracted with 0.02 mol L⁻¹ Cyphos IL 104, and 75% of molybdenum was stripped from the loaded organic phase with 2 mol L⁻¹ HNO₃ at A/O=1/1. McCabe Thiele diagrams were drawn to determine the number of stages required for the extraction and stripping of molybdenum. According to McCabe Thiele plots, two stages are required for both extraction and stripping of molybdenum at A/O=1/1 which were also confirmed by countercurrent simulation studies. Around 98% molybdenum was extracted in two countercurrent extraction stages with no co-extraction of cobalt and aluminum. Iron was removed from the loaded organic phase by scrubbing with 0.01 mol L⁻¹ HCl. Quantitative recovery of molybdenum is achieved in three countercurrent stripping stages at A/O=1/1. Trioxide of molybdenum was obtained from strip solution and was characterized by XRD, FE-SEM and EDX techniques. Molybdenum trioxide due to its distinctive electrochromic, thermochromic and photochromic properties is used as a smart material for sensors, lubricants, and Li-ion batteries. Molybdenum trioxide finds application in various processes such as methanol oxidation, metathesis, propane oxidation and in hydrodesulphurization. It can also be used as a precursor for the synthesis of MoS₂ and MoSe₂.

Keywords: Cyphos IL 104, molybdenum, spent Mo-Co catalyst, recovery

Procedia PDF Downloads 177