Carbon Monoxide Conversion Research Articles

A Comparative Study of Hydrothermally Leached Al3TM and Al3TM-Rh (TM=Zr, V, Ce) Intermetallic Compounds for Catalytic Oxidation of Carbon Monoxide.

Rise of the mute assassin "carbon monoxide (CO)" levels impact all aerobic life. The elevated rates of CO concentration endure climatic and geographical characteristics that exacerbate air pollution. Herein, a simple approach for hydrothermal leaching (HyTL) of Al3TM-Rh0.5 (Target material (TM)=Zr, V, Ce) and Al3TM (TM=Zr, V, Ce) intermetallic compounds produces leached products of ZrO2, VO2, and CeO2 with Rhodium (Rh) as an active component. The characterization result reveals the HyTL process and the presence of the active Rh element that elevated the performance of HyTL-Al3Zr-Rh0.5 towards CO conversion compared to other samples. Further, the cubic ZrO2 phase selectively forms after HyTL at 130 °C even though the formation of the cubic ZrO2 phase takes place at a high temperature. Moreover, the presence of Rh promotes higher catalytic activity in all the cases with low temperatures. The advancement in the present study towards the catalytic oxidation of CO over the hydrothermally leached ZrO2-Rh nanocatalyst guarantees the perspective of the aggregation-activation process.

Steering the Selectivity of CORR from Acetate to Ethanol via Tailoring the Thermodynamic Activity of Water

AbstractThe electrochemical conversion of carbon monoxide (CO) into oxygenated C2+ products at high rates and selectivity offers a promising approach for the two‐step conversion of carbon dioxide (CO2). However, a major drawback of the CO electrochemical reduction in alkaline electrolyte is the preference for the acetate pathway over the more valuable ethanol pathway. Recent research has shed light on the significant impact of thermodynamic water activity on the electrochemical CO2 reduction reaction pathways, but less is understood for the electrochemical reduction of CO. In this study, we investigated how the water activity at the electrified interface can be enhanced to adjust the selectivity between acetate and ethanol. We employed an ionomer modifier to lower the local concentration of alkali ions (via Donnan exclusion), successfully enhancing ethanol production while suppressing acetate formation. We observed a remarkable improvement in the Faradaic efficiency of ethanol and alcohol (i. e. ethanol, propanol etc), which reached 42.5 % and 55.1 %, respectively, at a current density of 700 mA cm−2. The partial current densities of ethanol and alcohol reached 698 and 942 mA cm−2 at 2000 mA cm−2. Furthermore, we achieved a 3.7‐fold increase in the ethanol/acetate ratio, providing clear evidence of our successful modulation of product selectivity.

Nanostructural evolution by applying various fuels in combustion design of CuZnAl mixed-oxides over HZSM-5 used in one-step production of CH3–O–CH3

The influence of different fuels (urea, ethylene glycol and citric acid) in combustion-based design of nano-structured CuO–ZnO–Al2O3/HZSM-5 catalyst was investigated. The catalytic performance were evaluated in a single step production of dimethyl ether form syngas. The X-ray diffraction, Field emission scanning electron microscopy, Transmission electron microscopy, Energy-dispersive x-ray, Temperature Programmed Reduction-H2, N2 Adsorption and Desorption isotherms and Fourier-transform infrared spectroscopy techniques were used to characterize physico-chemical properties of prepared nanocatalysts. The X-ray diffraction results clarified that application of citric acid increased relative crystallinity of Cu and Zn oxides existed in catalyst structure. The Fourier-transform infrared spectroscopy results demonstrated that the zeolite structure was not destroyed after CuO–ZnO–Al2O3/HZSM-5 introduction. The Field emission scanning electron microscopy and Transmission electron microscopy images illustrated that the nanocatalyst synthesized with citric acid has the highest porosity and less population of particle agglomerations. The highest amount of surface area was obtained when citric acid was used as fuel. According to Temperature Programmed Reduction-H2 profiles, the reducibility of nanocatalyst synthesized with citric acid is higher than other samples. The activity of the fabricated nanocatalysts for syngas to Dimethyl ether process were tested at temperature and pressure range of 225–300 °C and 10–40 bar, respectively. Using citric acid as fuel led to achieve greater amount carbon monoxide conversion and Dimethyl ether yield. Furthermore, stability test represented that the activity of this nanocatalyst remained quite stable during 1060 min.

CO-Free Fuel Processing of Water Gas Shift Feedstocks: Effect of Support on CuMn Spinel Performance

AbstractCleaning up carbon monoxide (CO) in water gas shift feedstocks is crucial for fuel cell applications. The catalytic transformation of CO in hydrogen-rich feeds poses a significant challenge in environmental catalysis. To address this issue, a range of Cu–Mn-based monometallic and bimetallic catalysts with diverse supports (such as alumina, silica, zirconia, and titania) were employed. Temperature programming techniques were utilised to observe the reduction and oxidation behaviours of these catalysts. The investigation involved testing CO oxidation at various temperatures over copper and manganese-based supported catalysts in the presence of H2O and CO2 (simulating realistic conditions). A positive impact of H2O on catalytic performance was noted, whereas CO2 had a suppressive effect. Furthermore, the specific support materials (Al2O3, SiO2, TiO2, and ZrO2) were studied to understand their roles in CO oxidation under realistic conditions. In the presence of water, alumina catalysts containing bimetallic metals (Cu–Mn) exhibited 100% CO conversion even at a lower temperature of 160 °C. Conversely, under the predominant influence of CO2, alumina catalyst (Cu–Mn) showed 55% CO conversion. The exceptional performance was attributed to CO preferential adsorption on highly active Cu–Mn sites and a small H2-oxidative atmosphere of the catalysts. The activity results highlighted the strong dependence of CO conversion on reaction temperatures, the presence of metals, and the types of supports. Overall, these findings suggest the potential use of these catalysts for H2 purification under realistic conditions. Graphical Abstract

Carbon monoxide conversion by anaerobic microbiome in a thermophilic trickle bed reactor

Biomethanation offers a promising route for the valorization of synthesis gas, yet significant challenges arise from the limited conversion of carbon monoxide (CO). This study investigated the adaptation of an anaerobic microbiome in a continuous trickle bed reactor (TBR) with CO as the sole carbon and energy source. We evaluated reactor performance and microbial community changes under different CO loading rates and gas retention times (GRT). Optimal performance was achieved at a CO loading rate of 5.16 Nm³ m⁻³ d⁻¹ and a GRT of 60.6 min, resulting in average production rates of 0.99 Nm³ m⁻³ d⁻¹ for CH₄ and 2.55 Nm⁻³ m⁻³ d⁻¹ for CO₂, with an 88 % CO conversion rate. Microbial analysis indicated that the community was dominated by the genus Methanothermobacter, known for its ability to utilize CO as a sole substrate, followed by a co-dominance of syntrophic acetate-oxidizing bacteria Syntrophaceticus. This syntrophic relationship between Methanothermobacter and Syntrophaceticus is expected to be crucial for the efficient CO conversion process. Additionally, the study proposes a two-reactor system for converting synthesis gas to grid-quality methane.

Highly Efficient Carbonylation of Propylene Oxide into β‐Butyrolactone Catalyzed over Co‐Al Bimetallic Species†

AbstractRational designation of the catalyst for efficient atom‐economic conversion of propylene oxide (PO) and carbon monoxide (CO) into β‐butyrolactone is of current significance. By employing the O,N,O‐tridentate ligands R1,R2LH2 (1–4), the aluminium compounds (R1,R2LAlCl)2 (R1,R2=H,H (5), tBu,tBu (6), Cl,Cl (7), Br,Br (8)) and the derived anion‐cation pairs [H,HLAl(THF)3]+[Co(CO)4]− (9) and [(R1,R2LAl)2Cl(THF)2]+[Co(CO)4]− (R1,R2=tBu,tBu (10), Cl,Cl (11), Br,Br (12)) as well as the aluminium‐cobalt bimetallic cluster compounds [(R1,R2LAl)2Cl(THF)][Co3(CO)10] (R1,R2=tBu,tBu (13), Cl,Cl (14), Br,Br (15)) were prepared. Compounds 9–12 efficiently catalyzed the PO carbonylation into β‐butyrolactone to achieve up 93.4–98.9 % yields while 13–15 gained 95.2–99.0 % yields all at 25 °C and 0.1 MPa CO pressure. The Lewis acidic property of the aluminium compounds 5–8 was investigated. The kinetic of the catalytic reaction using compound 10 was studied. The cooperatively catalytic reaction mechanism by the Co−Al bimetallic species is proposed.

Photochemical conversion of CO to C1 and C2 products mediated by porphyrin rhodium(II) metallo-radical complexes

Unimolecular reduction and bimolecular reductive coupling of carbon monoxide (CO) represent important ways to synthesize organic feedstocks. Reductive activation of CO through open-shell pathways, though rare, can help overcome the barriers of many traditional organometallic elementary reactions that are hard to achieve. Herein we successfully achieve the unimolecular reduction of CO to (TPP)RhCH2OSiR1R2R3 (TPP = 5,10,15,20-tetraphenylporphyrin), and the release of products CH3OSiR1R2R3, TEMPO-CH2OSiR1R2R3 and BrCH2OSiR1R2R3 in near-quantitative yield under visible light (420–780 nm), which involves radical formation from Rh-C bond homolysis. Bimolecular CO reductive coupling products, (TPP)RhCOCH2OSiR1R2R3, are then obtained via a radical mechanism. Subsequent treatment with n-propylamine, BrCCl3 or TEMPO under thermal or photochemical conditions afford small-molecule bimolecular reductive coupling products. To the best of our knowledge, homogeneous systems which reductively couple CO under photochemical conditions have not been reported before. Here, the use of an open-shell transition metal complex, that delivers more than one kind of small-molecule CO reductive coupling products bearing different functional groups, provides opportunities for useful CO reductive transformations.

Steering the Selectivity of CORR from Acetate to Ethanol via Tailoring the Thermodynamic Activity of Water.

The electrochemical conversion of carbon monoxide (CO) into oxygenated C2+ products at high rates and selectivity offers a promising approach for the two-step conversion of carbon dioxide (CO2). However, a major drawback of the CO electrochemical reduction in alkaline electrolyte is the preference for the acetate pathway over the more valuable ethanol pathway. Recent research has shed light on the significant impact of thermodynamic water activity on the electrochemical CO2 reduction reaction pathways, but less is understood for the electrochemical reduction of CO. In this study, we investigated how the water activity at the electrified interface can be enhanced to adjust the selectivity between acetate and ethanol. We employed an ionomer modifier to lower the local concentration of alkali ions (via Donnan exclusion), successfully enhancing ethanol production while suppressing acetate formation. We observed a remarkable improvement in the Faradaic efficiency of ethanol and alcohol (i.e. ethanol, propanol etc), which reached 42.5% and 55.1%, respectively, at a current density of 700 mA cm-2. The partial current densities of ethanol and alcohol reached 698 and 942 mA cm-2 at 2000 mA cm-2. Furthermore, we achieved a 3.7-fold increase in the ethanol/acetate ratio, providing clear evidence of our successful modulation of product selectivity.

Microtubular Electrodes for Efficient Electrochemical CO2/CO Reduction to Value-Added Products

The conversion of carbon dioxide (CO2) or carbon monoxide (CO) to commodity fuels and chemicals, empowered by low-carbon electricity, has attracted much attention as an alternative to conventional routes of chemical production [1]. Numerous studies have focused on CO2 reduction to CO or formic acid and active/efficient electrocatalysts with high Faradaic efficiencies (FEs) have been developed [2]. However, CO2 reduction to higher value C2+ products needs the critical C-C coupling step, and to date, Cu has been the main electrocatalyst for this conversion [3]. Electrochemical carbon monoxide reduction (CORR) to C2+ products has advantages over electrochemical CO2 conversion (CO2RR) as issues such as carbonation, and CO2 loss during CO2RR are omitted in CORR due to the stability of CO in alkaline solutions. Facing common challenges as CO2RR, CORR suffers more from mass transport resistance and intrinsically lower aqueous CO solubility. Therefore gas-diffusion electrodes (GDEs) are desired to boost the formation of triple phases and active sites to obtain higher reaction rates.Herein for the first time we design Cu-based HFGDEs for efficient CORR to C2+ products with ethylene as the main product. The pristine Cu HFGDEs showed low selectivity towards C2+ products. Therefore, we tuned the Cu catalyst shape morphology and orientated growth of nanocubes on the outer surface of HFGDEs by electrodeposition. Due to the efficient C-C coupling and high C2+ _selectivity of copper nanocubes with dominant Cu(100), the HFGDEs showed exceptionally high current densities in the 1.0 M KOH electrolyte, outperforming conventional GDEs tested for CORR under similar conditions. Compared with CO2RR in a bicarbonate medium, significantly higher current densities and FEs of C2+ products (>90%) and ethylene (>65%) were achieved when the HFGDE were used for CORR. Moreover, lower partial current densities of C2+ were obtained when using the hollow fibers in the non-GDE mode, confirming the significant performance of HFGDEs for achieving high-rate and selective CO reduction through maximizing triple-phase interfaces and local CO concentration. By increasing the concentration of KOH, an ethylene partial current density of 472 mA cm2- was obtained using the flow-cell reactor, indicating the promises of HFGDEs as an emerging electrode configuration for efficient CORR to C2+ products. Figure 1

Fe-MOF-74 Reactivity Explored: Comprehensive Computational Assessment of O and S Atom Influence on CO2 and CO Reduction Reactions

The conversion of carbon dioxide (CO2) and carbon monoxide (CO) into higher-value materials is crucial for addressing escalating levels of greenhouse gases in Earth’s atmosphere. Employing first-principles methods, we investigated the electrocatalytic reduction of CO2 and CO on two Fe-based MOFs: Fe2DOBDC and Fe2DSBDC. By directly comparing these MOFs, we aimed to discern the impact of introducing S atoms into the framework without changing the topological framework. Several chemical properties such as electronegativity, atomic radius, polarizability, and charge density are expected to lead to significant changes for the reduction reactions upon the replacement of O atoms with S atoms. CM5 atomic charge analysis highlights some of these differences by showing the equatorial Fe-O/S bonds of Fe2DSBDC are less polarized and result in smaller positive and negative charges on the Fe and O/S atoms, respectively. Additionally, the larger S atoms are expected to weaken adsorbate binding due to less favorable van der Waals interactions near the open-metal Fe site. Consequently, the less electropositive Fe site and the larger S atoms of Fe2DSBDC impede the adsorption of reduced CO2 and CO products, while the more electropositive Fe site and smaller O atoms of Fe2DOBDC strongly favor product adsorption. This implies that CO2 and CO reduction on Fe2DSBDC is likely to yield only 2e- products (HCOOH and CH2O, respectively), whereas Fe2DOBDC is expected to produce deeper reduction products (CH2O and CH4, respectively). This insight offers a foundation for constructing novel MOFs with tunable reaction behaviors by strategically replacing O atoms with heavier S atoms in the MOF scaffold.

Toward Sustainable Olefins: Electroreduction of CO2 to Multi-Carbon Olefins Using Trimetallic Cu-Rich Catalysts

The sustainable conversion of carbon monoxide (CO2) into value-added chemicals via electrochemical methods, powered by renewable electricity, is considered as a promising approach to meet the global energy demand and close the anthropogenic carbon cycle. However, this technology is in the early stage of development, particularly in the production of multi-carbon (C2+) hydrocarbons due to well-studied thermodynamic and kinetic barriers. To overcome these challenges, developing a catalyst with high activity and selectivity is crucial to minimize energy input and maximize the effectiveness of C2+ products formation.In this work, we will present our recent advancement on developing non-precious tri-metallic catalysts with copper-rich surface synthesized by our developed atomically controllable and environmentally friendly synthesis method. The developed nanostructured tri-metallic electrocatalysts by this method show remarkable selectivity and activity in the electrochemical conversion of CO2 to olefins. In particular, our electrochemical results show an overall C2+ olefine Faradaic efficiency (FE%) of 69% more specifically 58% ethylene and 11% propylene at a current density of -112 mA/cm² under applied potential of -2.8 V in an anion exchange membrane (AEM) electrolyzer. To gain a better understanding of the catalytic performance and find a structural-performance relationships for the developed materials, we performed several physicochemical and electrochemical characterization experiments, including X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), and X-ray photoelectron spectroscopy (XPS). We will discuss morphology and atomic structure changes of the developed materials under realistic conditions, with a specific focus on understanding how different trimetallic interfaces influence selectivity and activity in the electrochemical CO2 reduction reaction (eCO2RR).

Optimization of process parameters and medium components for carbon monoxide bioconversion with Clostridium autoethanogenum

AbstractClostridium autoethanogenum is a model microbe capable of converting carbon monoxide (CO) into bioethanol and useful biochemicals. Successful process optimization when using CO as the primary carbon source requires an understanding of the influence of process parameters and growth medium components on cell growth and end‐product formation. We conducted a full factorial analysis of the effects of CO total pressure, pH, yeast extract (YE), and cysteine concentrations on acetic acid, ethanol, and biomass production utilizing C. autoethanogenum with CO as the primary substrate. Maximum ethanol production of 0.71 g L–1 was obtained at a pH of 4.5, yeast extract concentration of 0.5 g L–1 , CO pressure of 1.8 atm, and cysteine concentration of 1.5 g L–1. There was a tenfold enhancement when the pH was lowered from 6 to 4.5 and the YE concentration was reduced to 0.5 g L–1. Response optimization using the reduced gradient algorithm confirmed these results. The information presented in this study could prove valuable for process engineering design by assisting with the selection of parameters that yield syngas blends specifically intended for increased ethanol production.

Modulating CO hydrogenation activity through silane functionalization of cobalt catalysts

Cobalt oxide (CoO) nanoparticles (NPs) were modified with different silanes (tetraethoxysilane – TEOS, triphenyl ethoxysilane – TPES, or trimethyl chlorosilane - TMCS) by dispersing the as-synthesized CoO NPs in n-hexane solutions containing the silanes. Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of these silanes on the cobalt surfaces even after reduction in hydrogen (H2) at 573 K. Modifying CoO-NPs with TEOS resulted in face-centred cubic (fcc)-cobalt phase upon reduction whereas TPES or TMCS modification induced a mixture of hexagonal close-packed (hcp)- and fcc-cobalt phases. The modification of cobalt surfaces with the silanes alters the adsorption properties of carbon monoxide (CO) on the catalytically active sites. Furthermore, temperature programmed desorption of CO (CO-TPD) showed that the amount of dissociatively adsorbed CO relative to amount of associatively adsorbed CO increases on silane-modified cobalt surfaces, which correlates with an improved rate of CO conversion in the Fischer-Tropsch CO hydrogenation.

Pre-pilot scale study of hydrogen production from biomass syngas via water-gas shift in Pd–Ag catalytic membrane reactor and dedicated hydrogen permeation unit

The water-gas shift reaction (WGS) was evaluated in two Pd–Ag membrane reactors operating in parallel and capable of processing 0.25 Nm3·h−1 of syngas. Various configurations, syngas compositions, and steam flow rates were explored within the temperature range of 300–350 °C and pressure range of 4–8bar. The performances were evaluated in a coupled configuration, consisting of a permeator and a membrane reactor operating in series, and single configuration of membrane reactor. Two syngas mixtures were fed and treated under different combinations of temperature, pressure, and steam/CO ratio. The syngas composition used was, in one case that typically produced by updraft gasifiers operated with air and having a content of H2 19.1 vol% and, in the second case, having content of 36.8 vol%, typically achievable by oxy-steam gasification. Carbon monoxide conversion, hydrogen permeation, and hydrogen permeability of membranes were determined. The use of these membranes effectively enhances the WGS reaction, overcoming the performances of a Gibbs reactor, and produces streams of ultrapure hydrogen. Competitive strong adsorption of CO was suggested from the permeability analysis and comparison with existing literature.

Zr doping on CeO2 nanocube catalysts to enhance oxygen storage capacity for Water-Gas shift reaction

Zr was doped on Co/CeO2 cubic catalysts to enhance oxygen storage capacity (OSC) in the water–gas shift (WGS) reaction using waste-derived synthesis gas. Zr concentrations (0, 0.22, 1.86, and 7.01 wt%) were changed systemically to see the effect of Zr on OSC. The analysis of the characteristics reveals that the newly synthesized catalysts demonstrate superior OSC compared to the CeO2 supported Co catalyst previously developed by our lab. The catalyst with the highest Zr content (7.01 wt%) demonstrated substantial carbon monoxide conversion after 50 h, highlighting the critical role of OSC in catalytic WGS stability. Conversely, a minimal Zr addition (0.22 wt%) resulted in the highest initial catalytic activity, which was attributed to an above-average Brunauer–Emmett–Teller surface area, Co dispersion, and relatively sufficient OSC. The findings emphasize that Zr doping considerably enhances the OSC of Co/CeO2 cubic catalysts, which is essentially linked to catalytic performance such as stability and activity. These insights confirm that precise Zr doping is a crucial strategy for modulating OSC, thereby enhancing the physicochemical properties of catalysts for improved efficiency in environmental and industrial applications, particularly in WGS reactions.

PRODUCTION OF SYNTHETIC HYDROCARBONS USING COBALT CATALYSTS BASED ON ZSM-5 ZEOLITE

In this work, cobalt catalysts based on zeolite ZSM˗5 were prepared by the triple impregnation method and chemically analyzed. Zirconium dioxide was used as a promoter (3 wt. %). Chemical analysis of the elemental composition and structure of the obtained catalysts was carried out using scanning electron microscopy. It is shown that the elemental composition of the catalysts with satisfactory accuracy corresponds to their given composition. Experiments for catalytic tests of the prepared catalysts were carried out on a laboratory Fischer-Tropsch synthesis unit and synthetic hydrocarbons were obtained. Comparative characterization of activity of the obtained catalysts with cobalt content of 10 % and 20 % has been carried out, dependence of carbon monoxide conversion and selectivity with respect to formation of gas hydrocarbons and yield of liquid products on temperature has been studied.

Ultralow doping of Zr species into Co3O4 catalyst enhance the CO oxidation performance

The oxidation of carbon monoxide (CO) has garnered significant interest for its application in treating automobile exhaust. In this study, we employed the sol-gel method to synthesize a series of cobalt-zirconium oxide catalysts with various Co/Zr ratios, aiming to catalyze the oxidation of CO effectively. The findings showed that the Co90Zr10 catalyst, with a cobalt-to-zirconium ratio of 90:10, not only exhibited exceptional catalytic efficiency, achieving a 90 % conversion of CO at 94 °C, but also sustained superior thermal stability and resistance to water. The presence of both cobalt defects and oxygen vacancies significantly enhances the catalytic activity, which is attributed to the doping of zirconium. The characterization analyses indicated the incorporation of zirconium into the Co3O4 spinel lattice modifies the valence states (Co3+/Co2+) and geometries (CoOh/CoTd) of the cobalt cations. This alteration results from a variety of partial electron transfers and substitution sites. Enhanced ratios of Co3+/Co2+ and CoOh/CoTd in the CoxZry catalysts lead to improved reducibility and oxygen mobility. Consequently, this facilitates the lower-temperature oxidation of intermediates during the catalytic conversion of CO. DFT result showed that the Co3O4 after Zr doped has lower adsorption energy and revealed the reaction mechanism of CO catalytic oxidation.

Recycling and characterization of spent catalyst: Carmoisine dye removal from water and carbon monoxide conversion to carbon dioxide in air

This study describes the recycling of the spent Co-Mo-Al2O3 catalysts in hydro-treating diesel fuel and subsequent application in purifying wastewater and air from harmful contaminants. A sodium carbonate solution was used for the selective extraction of molybdenum with an extraction efficiency of at least 90 %. As a result, Mo-Al2O3 material was obtained. The material was characterized by EDX and low-temperature nitrogen adsorption. The materials showed high activity and stability as a Fenton-type catalyst in the oxidative degradation of the carmoisine azo dye in aqueous solution with 98 % removal in 30 min having 8.0 g/L catalyst at pH 2.0 and 60 °C temp. The carbon monoxide conversion to carbon dioxide was 100 % at 475 °C. The present work is very useful for the purification of water by removing carmoisine dye and air by converting carbon monoxide to carbon dioxide.

Nano Technolgy Application to Enhance the Emission Control by Using Activated Carbons Modified by Magnesium Oxide

One of the fundamental processes for planet safety is the catalytic conversion of carbon monoxide (CO). CO has even been named one of the unseen toxins of this century. Inhaling CO can lead to hypoxic damage, neurological break, and even death. CO poisoning decays greenery life and accumulations in global warming and ozone layer depletion. CO is created in the atmosphere by the partial oxidation of carbon-containing mixtures. The primary origin of CO emissions is vehicles. Therefore, oxidizing contaminated CO to nonpoisonous CO2 under ambient conditions is essential for life protection in multiple applications. Additionally, low-temperature CO oxidation is crucial in reducing emissions at the cold start of an internal explosion in the engine. For controlling pollution, the available methods are pre-pollution control and post-pollution. This project depends on the post-pollution control method in Peugeot ROA automobiles using Activated Carbons Modified by Magnesium Oxide as a catalyst. An innovative catalytic converter design activated carbons modified by magnesium oxide nanoparticles as a catalyst to control pollution with different NPs lodgings and carbon structures. This proposed method aims for the reduction environmental pollution contributed by automobiles. It involves using more affordable materials than the existing rhodium nanoparticles, platinum, and palladium technique. The dispersion states of the grafted nanoparticles were examined with scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD), confirming the correlation between high grafted ratio states and improved properties. The nanocomposites' desired properties were significantly enhanced when the graft density was high.

CO electrolysis to multicarbon products over grain boundary-rich Cu nanoparticles in membrane electrode assembly electrolyzers

Producing valuable chemicals like ethylene via catalytic carbon monoxide conversion is an important nonpetroleum route. Here we demonstrate an electrochemical route for highly efficient synthesis of multicarbon (C2+) chemicals from CO. We achieve a C2+ partial current density as high as 4.35 ± 0.07 A cm−2 at a low cell voltage of 2.78 ± 0.01 V over a grain boundary-rich Cu nanoparticle catalyst in an alkaline membrane electrode assembly (MEA) electrolyzer, with a C2+ Faradaic efficiency of 87 ± 1% and a CO conversion of 85 ± 3%. Operando Raman spectroscopy and density functional theory calculations reveal that the grain boundaries of Cu nanoparticles facilitate CO adsorption and C − C coupling, thus rationalizing a qualitative trend between C2+ production and grain boundary density. A scale-up demonstration using an electrolyzer stack with five 100 cm2 MEAs achieves high C2+ and ethylene formation rates of 118.9 mmol min−1 and 1.2 L min−1, respectively, at a total current of 400 A (4 A cm−2) with a C2+ Faradaic efficiency of 64%.