Journal of Applied Research of Chemical -Polymer Engineering

Abstract Research subject: One of the common problems in natural gas transmission lines is congestion and pressure drop in gas transmission pipes due to the formation of gas hydrates. Gas hydrates are stable crystalline compounds that are formed from the contact of water molecules with some gas molecules of the right size and under the right thermodynamic conditions (low temperature and high pressure). These compounds are studied from both thermodynamic and kinetic perspectives. Despite many studies in the thermodynamic part of hydrates, the kinetics of hydrates require further study.
Research approach: To this end, in order to determine the equilibrium conditions of natural gas hydrate, 5 different experiments were conducted with a natural gas sample from Gas and Liquefied Gas Refinery 1300 in the temperature range of 285.5, 281.5, 276.21, 275.59, 273.92 Kelvin and pressure of 41.1, 28.2, 18.84, 13.4, 11.5 bar in a reactor using the constant volume method.
Main results: Based on the experimental data, the mass transfer coefficient was 0.243, 0.159, 0.153, 0.094, 0.131 meters per second, respectively, and the molecular diffusion coefficient was 4.516(×10-09), 4.785(×10-09), 1.175(×10-09), 2.847(×10-09), 1.147(×10-09) m2/s. These results show that with increasing reactor temperature (at constant pressure), the mass transfer coefficient decreases and the molecular diffusion coefficient increases. Also, with increasing pressure (at constant temperature), the mass transfer coefficient increases and the molecular diffusion coefficient decreases, which is consistent with empirical equations. Statistical analysis of the results revealed that the reactor pressure parameter has a greater effect on the mass transfer coefficient than temperature. Furthermore, statistical examination showed that temperature is a more influential parameter on the molecular diffusion coefficient (DAB) of natural gas in water.

Abstract Research subject: Following the implementation of primary and secondary recovery processes in hydrocarbon reservoirs, enhanced oil recovery (EOR) methods are employed to increase extraction efficiency further. Among the most prominent techniques within this domain is chemical enhanced oil recovery (CEOR), encompassing well-established methods such as polymer flooding, polymer–surfactant hybrid flooding, polymer–nanoparticle flooding, and alkaline–surfactant–polymer (ASP) flooding. Despite their proven efficacy, these conventional approaches are often hindered by high operational costs, technical and operational complexities, and potential environmental concerns. In light of these challenges, polymeric surfactants have recently emerged as a promising and viable alternative, offering the dual functionality of viscosity enhancement and interfacial tension (IFT) reduction in a single agent.
Research approach: This study presents a comprehensive review and critical evaluation of recent research efforts concerning the application of polymeric surfactants in oil recovery processes. Key mechanisms, including viscosity modulation, IFT reduction, and wettability alteration, were systematically analyzed. Furthermore, limitations associated with the synthesis of these materials, elevated production costs, and the fragmented nature of available field data were considered. The review seeks to identify performance trends and knowledge gaps to guide future investigations.
Main results: The findings indicate that, under most reservoir conditions, polymeric surfactants have the potential to significantly improve oil recovery factors. However, their widespread implementation is currently constrained by complex synthesis procedures, economic barriers, and the lack of extensive field validation. This research synthesizes the latest advancements and offers recommendations for future work, including formulation optimization, cost-reduction strategies, and the design of large-scale field trials to assess real-world performance.

Abstract Research subject: This research aims to revive outdated Kevlar fabrics for reuse in the manufacturing of polymer-based composite parts. As a polymer fiber with high tensile strength and significant resistance to impact and heat, Kevlar is used in various industries, including automotive, aerospace, and protective equipment manufacturing. This type of reinforcement alone does not give a good bond with polymer resins, and to create a strong bond, a conciliator (sizing agent) is used, which has a useful life. The physical and mechanical properties change over time due to environmental influences such as humidity, ultra-violet rays, and high temperature.
Research approach: In this research, among the thermal, mechanical, chemical, plasma, nanoparticles, and layering methods, the chemical method was chosen to revive outdated Kevlar fabrics. For this purpose, at first, three waste fabric samples were selected and finally, the tensile properties of regenerated and non-regenerated fabrics were compared according to the ASTM D638 standard tensile test.
Main results: The results showed that the chemically regenerated fabric had about 11.3% more tensile strength than non-regenerated fabrics, and the chemical regeneration process positively improved the mechanical properties of old Kevlar fibers. This achievement paves the way for the reutilization of aged fibers in advanced structures. This shows that the chemical regeneration process not only increases the mechanical strength of materials, but can also positively affect their durability and stability against environmental factors. In addition, this research provides an economic and ecological method for reviving old fibers, providing a basis for reducing industrial waste and reusing polymer materials.

Abstract Research subject: Multi-component catalysts based on metal-organic frameworks (ZIF-8), combined with various additives such as cerium oxide (CeO2) and zirconium oxide (ZrO2), have been developed separately to investigate the role that metal oxides, in combination with metal-organic frameworks, play in the conversion of CO2 to Methanol. The study seeks to explore how these metal oxides interact with ZIF-8 and contribute to improving the catalytic performance for the efficient conversion of CO2 into Methanol, which is an important process for reducing CO2 emissions and producing renewable fuels.
Research approach: The structural, physical, and chemical properties of the synthesized catalysts were meticulously analyzed using a variety of advanced techniques. These included XRD, FT-IR, BET, SEM, TGA, TPR, and H2/CO2 TPD. Unlike earlier studies focusing on a single oxide, this work highlights the comparative effect of two key oxides within the same catalytic framework using advanced characterization techniques. Cerium oxide (CeO2) plays a pivotal role in the catalytic system by creating strong basic sites, which are essential for activating CO2. It also facilitates the formation of different oxidation states (Ce3+ and Ce4+), which enhance the reducibility of the catalyst and increase its specific surface area. Meanwhile, zirconium oxide (ZrO2) significantly improves the dispersion of active sites within the catalyst structure, which leads to an increase in the number of active sites available for the CO2 hydrogenation process. Moreover, a controlled thermal treatment was applied to refine the formation and distribution of these active sites, resulting in an overall enhancement in catalytic performance.
Main results: The presence of cerium oxide improves the conversion of CO2 to Methanol by introducing more abundant and active basic sites, which facilitate the reaction. On the other hand, zirconium oxide improves the dispersion of active sites across the catalyst surface, leading to a significant increase in Methanol selectivity. These two metal oxides, when used in combination, play complementary roles in improving both the efficiency and selectivity of ZIF-8-based catalysts in the hydrogenation of CO2 to Methanol. The synergistic effect of these oxides makes the catalyst more effective, allowing for a more efficient CO2 conversion process.

Abstract Research subject: Poly (vinyl chloride) (PVC) is non-biodegradable, and the widespread use of conventional plasticizers, particularly phthalates, in its formulation poses significant risks to human health and the environment. In this research, various blends of PVC and poly (lactic acid) (PLA) with different ratios were prepared in an internal mixer. The effect of PLA content, as well as the influence of various plasticizers including dioctyl phthalate (DOP), dioctyl adipate (DOA), epoxidized soybean oil (ESO), and chlorinated paraffin wax, on the mechanical and biodegradability properties was investigated. Furthermore, the role of a compatibilizer in improving the distribution of the PLA phase and increasing the compatibility between the polymers was evaluated.
Research approach: Tensile testing and dynamic mechanical analysis (DMTA) were performed to study the mechanical behavior. Scanning electron microscopy (SEM) imaging was used to examine the morphology and the distribution of the PLA phase. In addition, a biodegradability test was carried out to analyze the degradation behavior of samples in the environment.
Main results: The results indicated that the PVC/PLA(90/10)-DOP blend exhibited a suitable distribution of the PLA phase within the PVC matrix, whereas a poor distribution of PLA in PVC was observed in the PVC/PLA(80/20)-DOP blend. The addition of a compatibilizer to the PVC/PLA(80/20)-DOP sample led to increased uniformity in the PLA phase distribution and improved tensile strength. Samples with higher PLA content showed greater biodegradability behavior, suggesting the role of PLA as a degradability-enhancing agent. The comparison of different plasticizers indicated that several of the ones used in this research exhibit properties comparable to DOP and may be considered as effective substitutes for it. The findings suggest that the simultaneous use of PLA and appropriate plasticizers such as ESO, along with the application of a compatibilizer, is an effective method for producing PVC samples with enhanced mechanical and biodegradability properties.

Abstract Research subject: Chemical process design is one of the foundational pillars for the advancement of oil, gas, and petrochemical industries. The inherent complexity and multidimensional nature of chemical processes have transformed process engineering projects into highly interdisciplinary collaborations. Consequently, beyond the challenges of process design itself, the synchronization and facilitation of cooperation among diverse engineering disciplines are among the core difficulties of such projects. The involvement of process design engineers as experts in chemical engineering is essential to address these challenges through direct engagement, indirect contribution, or overarching supervision.
Research approach: This study analyzes the structural framework of chemical process engineering projects, from the ideation phase to the end of the design life cycle, focusing on the complexities of oil, gas, and petrochemical systems. The roles of process design engineers across different project phases are identified and categorized. Their decision-making frameworks are modeled using process systems engineering (PSE) methodologies. To improve interdisciplinary collaboration and data integration, an ontology-based approach is adopted to define foundational concepts and standardize relationships between project components. Additionally, to clarify decision-making mechanisms and better understand the challenges and design stages, visualization techniques are applied to map information structures and depict the decision flows and responsibilities of process design engineers.
Main results: The findings demonstrate that process design engineers play a pivotal role in the success of engineering projects at three levels: direct involvement, indirect influence, and supervisory oversight. The role of process design engineers and their decision-making in addressing challenges within oil, gas, and petrochemical projects, across all stages from concept to operation, has been analyzed through the examination of process system characteristics. The application of these analytical tools in enhancing decision-making quality and improving understanding of process systems has been presented. Emerging AI tools significantly enhance the effectiveness of engineering decisions and contribute to cost and time reduction through enabling modeling, simulation, data analysis, and optimized decision-making. Moreover, the application of these tools improves understanding of complex industrial systems and enhances performance under uncertainty.