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The management and prevention of hydrates are crucial for the gas industry. This study delves into the intricate challenges associated with gas hydrate formation, with a specific focus on investigating the impact of corrosion by‐products on prevention strategies. Employing a distinctive methodology, the sapphire pressure–volume temperature (PVT) cell was utilized. Experimental tests were conducted using sodium chloride (NaCl) concentrations of 1% and 3% to simulate brine solution levels at the wellhead, incorporating 3% filtrate and unfiltered iron carbonate (FeCO3) as corrosion products associated with the production process. The 1% and 3% salt concentrations were chosen to encompass a broad range of temperature depressions, reflecting common industry standards for simulating realistic environmental conditions. PVT cell test conditions ranged from 80 to 200 bar, with increments of 40 bar. The experiments investigate the effects of common pipeline salts on a monoethylene glycol (MEG)/water mixture in the presence of methane gas at typical industry high‐pressure conditions. The investigation uncovers that the introduction of salts to water, methane, and MEG solutions serves as a hydrate inhibitor, with inhibitory effects directly correlated to salt concentration. While generally hydrate growth inhibition is beneficial in natural gas pipelines, the findings indicate that elevated salt concentrations and lower pressure conditions contribute to the formation of larger hydrates, heightening the risk of surface adhesion and potentially introducing complications in piping equipment, despite the decreased temperature at which these hydrates form due to the inhibitory effects of the salts. In particular, the mixed condition of 3% NaCl and 3% FeCO3 (filtered) has the strongest effect. Examination of hydrate formation temperature and macroscopic observations suggests that the existence of substantial precipitates, as evidenced in the unfiltered FeCO3 sapphire cell experiment, may have the potential to enhance hydrate growth. [ABSTRACT FROM AUTHOR]

In this research, successive electro-oxidation (EO) process was utilized to eliminate some of the primary organic contaminants in effluent wastewater, specifically phenol and chemical oxygen demand (COD). The performance of the electro-oxidation process was studied by using two graphite electrodes as anodes and three stainless steel electrodes as cathodes, which is a new strategy in this field. Taguchi method has been used to design experiments to approach the best experimental conditions for phenol and COD removal as significant responses. The best operating conditions that resulted in the maximum reduction of phenol and COD were current density (CD=25 mA/cm²), pH=4, support electrolyte (NaCl=2g/l), the distance between electrodes (Dist.=5mm), and time of 60 minutes. At these operating conditions, phenol and COD removal were 99.27% and 99.96%, respectively. This work provides important insights into a novel water and wastewater treatment method with a detailed analysis of the results. [ABSTRACT FROM AUTHOR]

Currently, there is a lack of detailed knowledge about methane (CH4) reactions on metal oxide surfaces. This reaction involves in different processes such as chemical looping combustion and catalytic carbon dioxide (CO2) reforming of CH4. In this study, in situ diffuse reflectance infrared Fourier transform spectroscopy was used to investigate CH4 reaction on three transition metal oxides (CoO, CuO, and α-Fe2O3) which are commonly used in these processes at temperatures ranging from 100 °C to 700 °C. The results show that CH4 is adsorbed on the metal oxide surfaces as methoxy and formate, and then the methoxy group reacts with the metal oxide lattice oxygen forming bicarbonate. Under the effect of the used reaction temperature, the bicarbonate decomposes to CO2 and water vapor. [ABSTRACT FROM AUTHOR]

The interactions of carbon dioxide (CO2) with metal oxides are a significant subject due to the numerous applications in which this reaction is involved. Although this reaction has been extensively studied by various infrared (IR) techniques, only a few (if any) have utilized in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). DRIFTS has an essential advantage over other traditional IR techniques in that it involves minimal sample preparation before analysis. In this work, CO2 adsorption on CoO, CuO, and α‐Fe2O3 nanoparticle surfaces was investigated by using DRIFTS. While the majority of species on CoO and CuO surfaces were observed as carbonate, on α‐Fe2O3 bicarbonate was more prevalent. [ABSTRACT FROM AUTHOR]

In this work, Fe3O4-SiO2 nanoparticles were synthesized, characterized, and applied as adsorbent material to remove methyl blue stain from an aqueous solution. The prepared nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and Brunauer-Emmett-Teller (BET) to determine the physical surface properties and correlate them to the adsorption efficiency. In addition, this study investigated the influence of several parameters on the removal percentage and adsorption capacity. Specifically, this study investigated the impact of changing the following parameters: pH (1 - 8), agitation speed (Uspeed; 100 - 350 rpm), initial methyl blue (MB) concentration (1 - 100 mg/L), adsorbent dose (0.05 to 0.15 g), and contact time (10 - 100 min). The characterization study reveals that the prepared material has an excellent surface area (385 ± 5 m2/g) and pore volume (0.31 cm3/g) which enhances the adsorption capacity. In addition, the prepared material showed excellent efficiency where the removal percentage reached 99.0±1% at the optimal operating conditions and the maximum adsorption capacity was 40 mg/g. This study delivers a full elucidation of the adsorption of MB dye by Fe3O4-SiO2 NPs which considers a promising inexpensive adsorbent. It also delivers important insight information about the adsorption process and the influence of each parameter, which fill the lack in this field. [ABSTRACT FROM AUTHOR]