Petroleum Chemistry最新文献

Novel pyrazoles namely 1-(3-(4-hydroxyphenyl)-5-(thiophen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)ethanone (HTPE) and 4-(5-(thiophen-2-yl)-4,5-dihydro-1H-pyrazol-3-yl) aniline (TPA) was synthesized from the condensation of chalcone derivatives with hydrazine hydrates, and their inhibitive characteristics for the corrosion of mild steel in 0.5 M hydrochloric acid solution were investigated to both chalcons and pyrazoles compounds by electrochemical method, and the scanning electron microscopy (SEM). The result shows the chalcone compound (ATP) has been essential in preventing mild steel corrosion in an acidic solution.

The study presents the development of a novel magnetic g-C₃N₄/MXene nano-photocatalyst for the efficient removal of pharmaceutical azithromycin from real wastewater. The escalating levels of pharmaceutical pollutants, particularly azithromycin, necessitate robust removal techniques. Photocatalysis, known for its affordability and eco-friendliness, is explored here, focusing on combining g-C₃N₄ with 2D MXene, offering stability, light absorption, and magnetic properties. The synthesis and characterization methods confirm the structural integrity and successful production of the nano-photocatalyst. High-performance liquid chromatography measures azithromycin levels in actual wastewater. Under sunlight exposure, the nano-photocatalyst exhibits exceptional photodegradation, removing 94% of azithromycin in just 120 min. Kinetic studies reveal pseudo-second-order kinetics and significant organic carbon removal efficiency exceeding 85% in less than 90 min is observed. Overall, the research highlights the potential of the magnetic g-C₃N₄/MXene nano-photocatalyst for sustainable and effective pharmaceutical contaminant remediation, positioning it as a promising solution for water treatment processes.

A five factor, three-level Central composite design (CCD) combining with response surface (RSM) was employed for maximizing crystal violet adsorption capacity (q_e) and removal dye from aqueous solution using a low-cost biosorbent prepared from a 50 : 50 mixture of two microalgae species: green (Chlorella vulgaris) and blue-green (Arthrospira platensis). The biosorbent was characterized by Fourier-transform infrared spectroscopy (FT-IR). Central composite design within response surface methodology (RSM) was employed to optimize five critical factors affecting crystal violet (CV) removal: pH 3‒11, biosorbent dose 250‒750 mg, temperature 20‒50°C, initial CV concentration 10‒30 ppm, and adsorption time 5‒15 min. MINITAB 18 software was used to maximize the adsorption capacity. The highest experimental crystal violet dye capacity of 140 mg/g was found in the lowest algae dose, consistent with calculated values based on numerical optimization. Kinetic modeling revealed the best fit with the pseudo-first-order model R² (0.9829), while equilibrium isotherm data were best described by the Langmuir model R² (0.9960). Thermodynamic parameters (ΔG⁰, ΔH⁰, and ΔS⁰) indicated the spontaneity and endothermic nature of the biosorption process. Finally, the study of mass transfer adsorption models was examined using the Weber and Morris model, the liquid film diffusion model, and Bangham and Burt’s model. When comparing these models, Bangham’s and Burt’s model has the highest R² (0.9971). The rapid dye uptake suggests the potential of this algal biosorbent for efficient and simultaneous dye removal in real-world contaminated environments.

For the first time, the study systematically investigates, the effects of the partial pressures of CO and H₂ on Fischer–Tropsch performance in a slurry bubble column reactor (SBCR) over an iron-based nanodispersion. It is shown that, over the tested temperature range, both decreasing CO partial pressure and increasing H₂ partial pressure enhance CO conversion. At CO/H₂ molar ratios of 1 : 1.5 to 1 : 2, reactor pressures of 1.9–2.2 MPa, and temperatures of 240–300°C, methane and C₂–C₄ hydrocarbons are selectively produced. On the other hand, at CO/H₂ = 1 : 1, 1.5–2.0 MPa, and 280–300°C, the predominant products were C₅₊ hydrocarbons. The CO/H₂ molar ratios of 1 : 1 to 1 : 2, 1.5–2.2 MPa, and 240–260°C are the optimal reaction conditions to maximize the selectivity towards oxygenates. The XRD data for the spent catalysts corroborate the correlations identified during the catalytic test.

This study proposes a method for selectively producing diesel-range hydrocarbons by combining Fischer–Tropsch synthesis (FTS) over a zeolite-supported catalyst with the oligomerization of C₅–C₁₀ alkenes over an H-Beta zeolite. FTS was carried out under gas recirculation conditions (H₂/CO = 1.85, 2.0 MPa). At a recirculation ratio of 16, the diesel content in the product increased to 54.6 wt %, compared to 38.7 wt % under flow-through conditions. Finally, by oligomerizing the alkene-enriched gasoline fraction from the FTS over H-Beta-18, the overall diesel fuel content was enhanced to 69%.

This study presents the first investigation into the hydrodeoxygenation (HDO) of syringol (2,6-dimethoxyphenol) and 2-methoxyhydroquinone—model compounds for lignin depolymerization products—using in situ synthesized NiMoS nanocatalysts. The catalysts were formed from oil-soluble precursors (Mo(CO)₆ and Ni(II) 2-ethylhexanoate) and elemental sulfur. By varying the reaction conditions (300–350°C, 1–7 MPa H₂, 15–300 min, and substrate-to-Mo molar ratios of 10.5 : 1 to 105.3 : 1), product distribution can be controlled to achieve 100% conversion and high yields of deoxygenated products, primarily cyclohexane. Characterization by XRD, HR-TEM, and XPS revealed that the catalyst formed during syringol conversion consisted of highly dispersed three-layer nanoparticles (average length: 4.3 nm), dominated by MoS₂ (81.5%) and a Ni–Mo–S active mixed phase (80.4%). The proposed HDO pathway for syringol proceeds through initial demethoxylation to guaiacol and phenol, followed by their subsequent deoxygenation and hydrogenation.

This study investigates the synthesis and performance of iron–polymer composite catalysts for the conversion of syngas to higher alcohols. A promoted Fe–polyvinyl alcohol (PVA) composite catalyst, with a formulation denoted as 20Fe/2Al–2Mn–2K–2V/PVA, was synthesized via the organic matrix method. Its physicochemical properties and catalytic performance were evaluated. X-ray diffraction (XRD) analysis and Fourier transform infrared (FTIR) spectroscopy revealed that heat treatment facilitated the formation of active phases (Fe₃O₄, χ-Fe₅C₂, and Fe₇C₃), which were stabilized within a carbon matrix featuring a polyconjugated bond network. The resulting composite exhibited high catalytic activity in CO hydrogenation following hydrogen pre-reduction. The reduced catalyst achieved 82% CO conversion at 320°C, and the content of higher alcohols in the hydrocarbon phase reached 27 wt % with a marked predominance of heavy alcohols (C₈₊/C₄–C₇ ratio ≈ 2.1).

Tandem reactions based on hydroformylation are an alternative route from olefins to the products of high value, whose classical synthesis procedures involve several steps. Reduction of the number of synthesis steps, equipment required, separation and purification procedures make tandem reactions promising for the development of less power- and resource-consuming procedures for producing a wide range of demanded compounds. Search for effective heterogeneous multifunctional catalysts for tandem reactions based on hydroformylation allows solving problems associated with the catalyst separation and recycling. The most important examples of using heterogeneous catalytic systems for reductive hydroformylation, hydroaminomethylation, hydroformylation– acetalization, and hydroformylation–aldol condensation are considered in this review. Key advantages in this field, operating principles of multifunctional catalysts, and the existing drawbacks that presently restrict the use of such catalysts are discussed.

This study investigates ammonia decomposition over a series of cobalt/silica gel catalysts with the loading of active metal varying from 2.1 to 32.4 wt %. The reaction was conducted in a continuous-flow reactor at temperatures between 400 and 550°C and a weight hour space velocity (WHSV) of 3000 h^–1. The catalysts were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X–ray diffraction analysis (XRD), multimolecular Brunauer–Emmett–Teller (BET) adsorption, and hydrogen temperature-programmed reduction (H₂-TPR). The results demonstrate that catalytic activity is dependent on cobalt content, with an optimal loading of 15–20 wt % providing the highest catalytic performance.

The composition of gaseous products formed during hydroupgrading of a model feedstock containing benzothiophene and 2-methylnaphthalene over unsupported (dispersed) Ni–Mo sulfide catalysts under the water gas shift reaction conditions (reaction of carbon monoxide with water) was studied. The influence of the reaction conditions (Т = 340–400°C, Р = 5 MPa (at 25°C), t = 4–10 h) on the conversion of individual feed components and composition of gaseous products was examined. The process conditions ensure in situ hydrogen generation (Н₂ content 25–30 vol %) and formation of hydrocarbon gases by methanation and hydrogenation of CO and СО₂ (СН₄ content up to 50 vol %, content of С₂–С₄ hydrocarbons 23–30 vol %). For the model feedstock with equimolar component ratio, at 360–380°C, CO pressure of 5 MPa (at 25°C), and water content of 10 wt %, the 2-methylnaphthalene conversion in 8–10 h does not exceed 30–34%, whereas for the benzothiophene it reaches 100% already in 4 h.