Petroleum Chemistry最新文献

This study investigates the kinetics of deactivation of a commercial NaY zeolite catalyst in alkylation of aniline with methanol due to coke deposition. In order to identify the accumulation trend, composition, and localization of coke deposits, a series of zeolite catalyst samples differing in reactor residence time were obtained. The catalysts and the accumulated coke deposits were characterized by X-ray fluorescence analysis, X-ray powder diffraction, TGA/DTA, SEM, low-temperature nitrogen adsorption, ²⁷Al and ¹³C MAS NMR, NH₃-TPD, and GC/MS. The coke species deposited on the catalyst during the reaction were found to mostly consist of long-chain aliphatic compounds (mainly alkanes) and heterocyclic aromatics. Both the TGA and GC/MS data showed that the relative content of aliphatic compounds increased with the progress of the catalyst deactivation. Moreover, the variation in the zeolite’s interplanar distances (measured by XRD) showed that the aliphatics were mainly localized in the zeolite pores.

The study investigates the effects of synthesis conditions on the physicochemical properties and biological activity of Beta zeolites. Specifically, it addresses the effects of the tetraethylammonium hydroxide (TEAOH) content in the reaction mixture on the crystallinity, particle size and morphology, textural properties, acidity, and hemolytic activity of the zeolites synthesized. Reducing the TEAOH content by factors of 2, 4, and 6 compared to the reference composition was found to lower the zeolite crystallinity, increase the mean particle size (from 240 to 515 nm), change the particle morphology, and reduce the concentration of acid sites (from 822 to 638 µmol/g). Hemolytic activity tests demonstrated that the zeolite toxicity for human erythrocytes increased with a reduction in the TEAOH content.

The hydraulic system plays a role in drilling operations significantly impacting drilling efficiency and costs. This study extensively reviews the literature on optimizing bit hydraulics from 2012 to the present. Employing a systematic review approach, the study identifies and synthesizes key trends and findings in bit hydraulic optimization. Getting the most out of your drilling operation starts with a well-tuned system, especially when drilling through tough rocks like shale. By carefully designing and maintaining your hydraulics and paying close attention to things like nozzle size, weight applied to the drill bit, and how fast it spins, you can significantly improve your drilling speed and keep your costs down. The review addresses a primary challenge: “balling,” where cuttings accumulate on the bit face, impeding the drilling process. A well-optimized bit hydraulic design prevents balling and enhances the bottom-hole cleaning, mitigating disruptions in drilling activities. This paper contributes to a nuanced understanding of the importance of bit hydraulic optimization in drilling operations, presenting a detailed overview of relevant research papers. The inclusion of diverse perspectives and methodologies enriches the discourse surrounding hydraulic optimization. The exploration of concepts such as Bit Hydraulic Horsepower, Bit Hydraulic Optimization, Bit Impact Force, Hydraulic Optimization, and Nozzle Velocity further illuminates the multifaceted nature of bit hydraulic optimization and its broader implications for advancing the efficiency and cost-effectiveness of rotary drilling operations.

The use of Gaviscon expired drug as the corrosion inhibitor on the carbon steel was studied in the 0.1 M HCl solution at 303, 313, 323 and 333 K by electrochemical method. Gaviscon was demonstrated to be an effective inhibitor for carbon steel, the efficiency reached 80.7% at concentration of inhibitor 24 mL/L at 303 K, 91.973% for 48 mL/L at 313 K, 89.42% for 48 mL/L at 323 K and 97.81% for 24 mL/L at 333 K. The polarization resistance of Gaviscon was revealed, and the highest value was 121.758 for 24 mL/L at 333 K. The surface morphology of the carbon steel was analyzed using scanning electron microscopy (SEM) to show the film randomly distributed throughout the entire carbon steel surface. The antibacterial activity of the inhibitor was also tested by agar well diffusion which exhibit that no inhibition zone was observed, indicating that the Gaviscon drug was reactivity against E. coli. and S. aureus bacterial. Fourier-transform infrared spectroscopy (FTIR) for the Gaviscon drug confirmed the inhibitory role of inhibition efficiency.

The current paper presents to study effect of consuming a direct slot jet inside a square channel to increase the heat transfer convection in a channel prepared with a heated block and slot jet with different nozzle arrangements. In numerical solution, to construct a two-dimensional domain for simulation, the SOLIDWORKS 2018 software was used, and the numerical tool (ANSYS Fluent Workbench 2020 R2) is employed. The study included the effects of the following parameters such as slot Nozzle opening d = 3, 4, and 5 mm, slot Nozzle distance to opening ratio x/d = 2, 4 and 8, slot Nozzle velocity v_j = 1, 2, 4 m/s, Heat flux q′′ = 1000 W/m², Duct inlet velocity u = 1 m/s, slot Nozzle hit h = 3.5 cm and slot nozzle types flat, converge, diverges. The present numerical study uses a computational domain of a square duct with a length of 90 cm and a side dimension of 20 cm, which is used for air passage. The main airflow from the surroundings entered the channel inlet to achieve a fully developed flow is about 42.5 cm. The results showed that using the convergent nozzle, which increased in Nu by 73% compared to that of the divergent nozzle, and the enhancement of Nu is 77% associated with that of the flat nozzle when using the convergent Nozzle at x_j = 6 mm and d_j = 3 mm.

Spouted bed reactors (SBRs) are highly valued for their effectiveness in chemical and biochemical processes due to their mixing and heat transfer capabilities. Understanding the heat transfer mechanisms in these reactors is necessary. This research delves into the heat transfer behavior of SBRs, which plays a role in enhancing their performance under operational conditions. The study conducted experiments to measure the heat transfer coefficient (HTC) at varying gas velocities (ranging from 0.32 to 0.74 m/s) at radial positions (r/R = 0, ±0.28, ±0.56, and ±0.85) and axial levels (H/D = 0.8, 2.1, and 3.5) within the spouted bed (SB) column using a technique, for the assessment of local heat transfer coefficients (LHTCs). The results we obtained revealed the velocity of the gas, its radial position in the reactor, and its axial height. For instance, higher gas speeds led to heat transfer efficiency and variations in radial positions highlighted how the reactor’s shape influences heat transfer dynamics. It’s worth noting that increasing the gas speed from the lowest to the level tested resulted in a 25% increase in heat transfer coefficients. These discoveries provide insights for improving the design and performance of SBRs with ranging applications in industries that rely on effective heat transfer processes.

A series of micro–mesoporous ZSM-5 zeolites with SiO₂/Al₂O₃ molar ratios ranging from 40 to 280 were synthesized hydrothermally using natural aluminosilicate halloysite nanotubes (HNTs) as a precursor for silica and alumina and as a co-template for the generation of mesopores. The physicochemical properties of the synthesized materials were characterized by energy dispersive X-ray fluorescence, X-ray diffraction, scanning and transmission electron microscopy, low-temperature nitrogen adsorption–desorption, and temperature-programmed ammonia desorption. Using the zeolite sample with an optimal combination of physicochemical properties, a Pt catalyst was prepared and tested in hydroisodewaxing of a hydrotreated diesel fuel (DF) feedstock. The catalyst supported on the HNT-based zeolite exhibited high performance in the isodewaxing of middle distillates, thus producing arctic diesel fuels at lower temperatures than those recorded for the catalyst supported on a commercial zeolite with a similar SiO₂/Al₂O₃ ratio.

This review provides an analysis of the advances in the development of zeolite catalysts for propane dehydrogenation reported over the past two decades. It discusses the main distinctive features of the industrially important reaction of propane dehydrogenation to propylene, including its capabilities, limitations, mechanism, and the actually achieved catalytic performance parameters such as feed conversion degree and propylene selectivity. Particular emphasis is placed on the stability of the catalytic parameters in time on stream and in reaction-regeneration cycles. An overview of the existing strategies for the synthesis of metal-based and oxide-based catalysts supported on molecular sieves is provided. To ensure a better understanding of the current research trends, the advanced approaches developed in recent years are discussed in a separate section. For each catalyst class, their catalytic performance is compared with that of the oxide-based catalysts commonly applied for this process. Particular attention is paid to research on “structure–catalytic performance” and “synthesis conditions–structure” correlations for active sites. Finally, conclusions are made regarding the most promising strategies that may be of use for the development of a new generation of industrial catalysts.

Metals’ potential hazards have drawn greater attention to the influence of metal pollution on water, making it a crucial subject of study in recent environmental research. This research aligns with the Sustainable Development Goals (SDGs), that aim to protect the world by addressing environmental concerns. As a consequence, understanding the impact of metal pollution on water is an essential aspect of the SDGs’ efforts to improve environmental preservation. This study provides insight into the removal of zinc ions from industrial wastewater using emulsion liquid membrane (ELM) technology. A study was conducted to investigate the use of ELM technology for removing zinc ions from industrial wastewater. Previous studies have shown that ELM can easily remove metals in their ionic form, but the presence of other organic or inorganic compounds like sulfates, phosphates, and carbonates in industrial wastewater increases their solubility and complexity of the removal. To develop the liquid membrane, a surfactant called Sorbitan monooleate (Span 80), an extractant called bis-2-ethylhexyl phosphoric acid (D2EHPA), hydrogen chloride as a reagent, and kerosene as a diluent were used. The study investigated the impact of surfactant concentration, homogenizer speed, extractant concentration, and external phase pH on zinc ion removal using a Box-Behnken design based on Response Surface Methodology (RSM). The results showed that surfactant concentration and pH had the greatest impact on removal efficiency, while homogenizer speed and surfactant extractant had a lower impact on zinc removal. The investigation adjusted numerous parameters to achieve a zinc recovery rate of more than 93% from the bioleaching solution. The most beneficial conditions were a stirring speed of 250 rpm for 10 min, 4.75% v/v Span 80, a homogenizer speed of 11 212 rpm for 8 min, a feed phase pH of 5 or 4.9, and 6% v/v D2EHPA in kerosene.

In this study, titanium dioxide (TiO₂) nanoparticles were prepared hydrolysis and condensation process. To obtain the anatase and rutile phases, the prepared product was subjected to a calcination process at a temperature of 400 and 700°C. Nanocomposites were adjusted from polymer blend of polyvinyl alcohol (PVA), polyethylene glycol (PEG), and polyvinylpyrrolidone (PVP) as a matrix with specific percentages (PVA 60, PEG 10, and PVP 5 wt %), and different concentrations (0 and 25 wt %) of TiO₂ NPs in the anatase and rutile phases. Several description techniques like X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), and energy dispersive spectroscopy (EDS) are utilized to investigate the impact of temperature on the crystalline size, crystalline phase, and shape of produced TiO₂ nanoparticles. XRD patterns show the presence of sharp peaks which proved that it had high degree of crystallization. The anatase phase formation occurs at 400°C, while the transition to rutile phase occurred at 700°C as a result of calcination process. The crystallite size was determined using the Scherer and Williamson‒Hall (W‒H) equations, micro-strain, degree of crystallinity, volume of the unit cell, and dislocation. An increase in calcination temperature leads to increase in both crystalline size and degree of crystallinity. FE-SEM micrographs reveal that increasing the temperature led to rise the size of TiO₂ nanoparticles. In the anatase phase, the particles exhibit a spherical shape, while in the rutile phase they often have a prismatic shape. The calcination at 700°C is considered more desirable and applicable, because of the incorporation of rutile with anatase—the heterophase—into the crystal structure. It leads to synergistic effects between the two crystal structures due to increased thermodynamic stability, which makes it effective in photodegradation of various pollutants in the environment.