Methyl mercaptan is a sulfur-based chemical found as a co-product in produced natural gas and it causes corrosion in pipelines, storage tanks, catalysts, and solid adsorption beds. To improve the quality of methane produced, researchers have studied the use of metal oxides and aluminum silicates as catalysts for removing mercaptan. However, there are restrictive limitations on the efficiency of metal oxides or aluminum silicates as adsorbents for this application. Therefore, this study investigated the performance of these materials in a fixed-bed reactor with simulated natural gas streams under various operating conditions. The testing procedure includes a detailed assessment of the adsorbent/catalysts by several techniques, such as Braeuer–Emmett–Teller (BET), Scanning Electron Microscope (SEM), Energy-Dispersive X-ray Spectrometry (EDS), and X-ray Photoelectron Spectroscopy. The results revealed that metal oxides such as copper, manganese, and zinc performed well in methyl mercaptan elimination. The addition of manganese, copper, and zinc oxides to the aluminum silicate surface resulted in a sulfur capacity of 1226 mg S/g of catalyst. These findings provide critical insights for the development of catalysts that combine metal oxides to increase adsorption while reducing the production of byproducts like dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) during methyl mercaptan removal.

Methyl Mercaptan is a sulfur-based chemical found as a co-product in produced natural gas and causes corrosion in pipelines, storage tanks, catalysts, and solid adsorption beds. To improve the quality of methane produced, researchers studied the use of metal oxides and aluminum silicates as catalysts for removing mercaptan. However, there are restricted limitations on the efficiency of metal oxides or aluminum silicates as adsorbents for this particular application. Therefore, this study investigated the performance of these materials in a fixed-bed reactor with simulated natural gas streams under various operating conditions. The testing procedure includes a detailed assessment of the adsorbent/catalysts by several techniques, such as Braeuer-Emmett-Teller (BET), Scanning Electron Microscope (SEM), Energy-Dispersive X-ray Spectrometry (EDS), and X-ray Photoelectron Spectroscopy. The result revealed that metal oxides such as copper, manganese, and zinc performed well in methyl mercaptan elimination. The addition of manganese, copper, and zinc oxides to the aluminum silicate surface resulted in a sulfur capacity of 1226 mg S/g of catalyst. These findings provide critical insights for the development of catalysts that combine metal oxides to increase adsorption while reducing the production of byproducts like dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) during methyl mercaptan removal.

The presence of toxic, corrosive, and environmentally harmful sulfur compounds within natural gas streams necessitates their removal to ensure compliance with fuel quality standards and regulations. Previous studies into MMOs (mixed metal-oxides) as adsorbents or catalysts for sulfur compound removal have generally focused on hydrogen sulfide (H₂S); however, few studies have assessed the removal of organic sulfur compounds such as ethyl mercaptans. The purpose of this research is to investigate the effects of various preparation routes on the performance of supported metal-oxide catalysts that remove ethyl mercaptans from natural gas; specifically, filtration-based and evaporation-based catalyst synthesis methods were investigated. A set of different catalysts—Mn, Cu, Zn, Ni, and a composite (Mn-Cu-Zn-Ni)—were prepared using filtration or evaporation solvent removal in this research and characterized by BET, FTIR, XRD, SEM, EDS, and XPS, and their sulfur-removal performance was evaluated through fixed-bed breakthrough experiments under representative operating conditions (25 °C, 200 psi, 36 mL/min). The results demonstrate that catalysts prepared via evaporation consistently exhibit greater sulfur adsorption performance compared to catalysts prepared through filtration, which is consistent with improved surface oxide exposure. Structural characterization further showed that evaporation-assisted preparation promoted improved surface oxide development, greater surface heterogeneity, and more accessible surface morphologies. Among the investigated catalysts, evaporation-prepared Mn and Cu catalysts achieved the highest breakthrough times of approximately 1410 min and 1350 min, respectively, exceeding the commercial benchmark catalyst (1200 min) under identical operating conditions. These findings demonstrate that the evaporation method enables more effective utilization of surface metal-oxide active sites involved in sulfur adsorption and surface redox interactions. Overall, this work establishes evaporation as a superior and scalable preparation strategy for metal oxide catalysts and provides important structure-performance insights for the design of cost-effective catalysts for industrial natural gas desulfurization, particularly for the removal of organic sulfur compounds such as ethyl mercaptan from natural gas.

The presence of toxic, corrosive, and environmentally harmful sulfur compounds within natural gas streams necessitates their removal to ensure compliance with fuel quality standards and regulations. Previous studies into MMOs (mixed metal oxides) as adsorbent or catalysts for sulfur compound removal have generally focused upon hydrogen sulfide (H₂S); however, few studies have assessed the removal of organic sulfur compounds like mercaptans. The purpose of this research is to investigate the effects of various preparation routes on the performance of supported metal-oxide catalysts that remove mercaptans from natural gases; specifically, filtration-based and evaporative based catalyst synthesis methods were investigated. A set of different catalysts; Mn, Cu, Zn, Ni and a composite (Mn-Cu-Zn-Ni) were prepared using filtration or evaporation solvent removal in this research and characterized by BET, FTIR, XRD, SEM, EDS and XPS, and their adsorption performance was assessed through fixed-bed breakthrough experiments under representative operating conditions (25°C, 200 psi, 36 mL/min). The results demonstrate that catalysts prepared via evaporation consistently exhibit greater sulfur compounds adsorption performance compared to catalysts prepared through filtration method, primarily due to enhanced retention of active metal species and improved surface accessibility. As confirmed from the characterization, all these improvements result from the fact that the evaporation method enhances the interaction between the metals and oxygen (FTIR); increases the amount of oxides formed as well as improves their distribution (XRD); provides access to more available metal surfaces (XPS/EDS); and creates pore structures and morphologies that are more open and accessible (SEM/BET). Among the catalysts studied, the Mn and Cu catalysts prepared by evaporation achieved the highest breakthrough times 1410 minutes and 1350 minutes, respectively, exceeding the performance of a commercial benchmark catalyst with breakthrough time of 1200 minutes under identical conditions. These findings demonstrate that the evaporation method enables more effective utilization of metal-oxygen active sites and significantly enhances sulfur adsorption capacity. Overall, this work establishes evaporation as a superior and scalable preparation strategy for metal oxide catalysts and provides important structure performance insights for the design of cost-effective catalyst for industrial natural gas desulfurization, particularly for the removal of organic sulfur compounds from natural gas.

The removal of sulfur compounds such as ethyl mercaptan from natural gas remains a critical challenge due to their detrimental effects on downstream processes, catalyst poisoning, and environmental emissions. In this study, a series of halloysite-supported transition metal oxide catalysts was synthesized and evaluated for the removal of sulfur compounds from natural gas at 25 °C, 200 psi, and 36 mL/min, using 0.5 g of the catalyst. The nanotubular structure and dual surface chemistry of halloysite promote enhanced metal dispersion and improved mass transfer. Single-metal (manganese, copper, zinc, and nickel) catalysts were developed and tested, after which a multi-metal oxide (base) catalyst comprising a composite of the single metals (Zn-Cu-Mn-Ni) was developed as a base catalyst to combine adsorption-active and redox-active functionalities, and its performance was further enhanced by the addition of palladium as promoter. A combination of analytical techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform infra-red spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) analysis, scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS), provided evidence that highly dispersed metal oxide phases were formed and the halloysite structure was preserved. XPS data showed the presence of oxidation states of metals that were active (Zn²⁺, Cu²⁺, Ni²⁺, Mn³⁺/Mn⁴⁺ and Pd²⁺), an indication of a redox-active surface for sulfur interaction. Results from the breakthrough experiments showed that the base catalyst significantly improved sulfur removal compared to single-metal catalysts, while the Pd-promoted catalyst exhibited the highest performance, with a breakthrough time of 630 min. Palladium was incorporated at low loading as a promoter, enhancing adsorption performance while maintaining a favorable balance between efficiency and material cost. This enhancement is attributed to synergistic interactions between adsorption-active sites and redox-active species, as well as improved electron transfer facilitated by palladium. The results demonstrate that rational design of multi-metal oxide catalysts supported on naturally occurring halloysite provides an effective and scalable approach for sulfur removal from natural gas, with strong potential for industrial applications.