Chain Growth Reactions Research Articles

Assessing the influences of kinetics and intrazeolite diffusion on propene oligomerization product selectivity in MFI zeolites

The inherently coupled influences of kinetics and intrazeolite diffusional constraints, together with the concurrent changes in zeolite properties among materials crystallized by conventional synthesis methods, obscure the relationship between propene oligomerization product selectivity and zeolite properties. Herein, we use a suite of MFI zeolites crystallized with independently varied H+-site density (0.3–5.7 H+/u.c.) and crystallite size (0.1–0.9 μm) together with effectiveness factor formalisms to assess the influences of kinetics and intrazeolite diffusional constraints on propene oligomerization selectivity, and the independent contributions of H+-site density and crystallite size to these influences. Extracting the kinetic influences of MFI properties and reaction conditions on propene oligomerization selectivity requires data measured at conditions where the extent of intrazeolite diffusional constraints imposed by products that occlude within MFI micropores and decrease effective diffusivity is fixed. Applying this framework to analyze product selectivity on MFI samples of varied crystallite size (0.3 H+/u.c.) reveals that selectivity to higher-rank products decreases with crystallite size because larger crystallites cause more severe intrazeolite propene concentration gradients, thereby decreasing rates of trimerization and higher-rank oligomerization reactions disproportionately relative to dimerization. MFI samples of higher H+-site density exhibit lower selectivity to higher-rank products, but a higher selectivity to oligomer products, reflecting differences in both kinetic rate constants and the composition of occluded products among these samples. Together, these findings demonstrate and rationalize the influences of H+-site density and crystallite size on propene oligomerization selectivity on MFI zeolites and provide a framework through which selectivity in transport-limited systems involving chain-growth reactions can be evaluated.

Dynamic Insights into the Growth Mechanisms of 2D Covalent Organic Frameworks on Graphene Surfaces.

Producing high-quality two-dimensional (2D) covalent organic frameworks (COFs) is crucial for industrial applications. However, this remains significantly challenging with current synthetic techniques. A deep understanding of the intermolecular interactions, reaction temperature, and oligomers is essential to facilitate the growth of highly crystalline COF films. Herein, molecular dynamics simulations were employed to explore the growth of 2D COFs from monomer assemblies on graphene. Our results showed that chain growth reactions dominated the COF surface growth and that van der Waals (vdW) interactions were important in enhancing the crystallinity through monomer preorganization. Moreover, appropriately tuning the reaction temperature improved the COF crystallinity and minimized the effects of amorphous oligomers. Additionally, the strength of the interface between the COF and the graphene substrate indicated that the adhesion force was proportional to the crystallinity of the COF. This work reveals the mechanisms for nucleation and growth of COFs on surfaces and provides theoretical guidance for fabricating high-quality 2D polymer-based crystalline nanomaterials.

Theoretical Investigation of Bimolecular Carbon Chain Growth Reactions in the Interstellar Media.

Detection of molecular anions in interstellar media implies that negatively charged species play a prominent role in astrochemical reactions. Among the observed species, carbon chain anions are important, as they can be precursors for the production of complex organic molecules. These anions can form either via direct electron attachment to the corresponding neutral species or through chain growth reactions of smaller anions, resulting in longer chains. In a recent study, crossed beam experiments coupled with velocity map imaging techniques were used to investigate the carbon chain growth reaction C2n- + C2H2 → C2n+2Hm- + H2-m (n = 1-3, m = 0,1). Products and branching ratios were established from experimental data. In the present work, electronic structure calculations and on-the-fly direct dynamics simulations were used to study these reactions. Energy profiles were investigated by using different density functional methods. Direct trajectory simulations were performed at the experimental collision energies using the B3LYP/6-31+G* level of theory. Trajectory analysis showed a variety of reaction pathways, and detailed atomic-level reaction mechanisms are presented.

Designing a Mordenite Catalyst with Enhanced Acidity for Dimethyl Ether Carbonylation by Engineering Open Sn Sites

Due to their tunable acidity, shape selectivity, and excellent stability, zeolites are of great importance as solid acid materials in industrial catalysis. Tuning the properties of the acid sites in zeolites allows for the rational design and fabrication of catalysts for target reactions. Dimethyl ether (DME) carbonylation, a critical chain-growth reaction for C1 resource utilization, is selectively catalyzed by the Brønsted acid sites within the eight-membered rings (8-MRs) of mordenite (MOR). It is anticipated that strengthening the Brønsted acidity—particularly in 8-MRs—will improve the catalytic performance of MOR. In this work, density functional theory (DFT) calculations are first employed and the results used to design a modified MOR with stannum (Sn) and to predict the corresponding changes in acidity. Guided by the theoretical studies, a series of Sn-modified MOR are synthesized via a defect-engineering and subsequent heteroatom-substitution strategy. After partial desilication, isolated tetrahedral Sn species in an open configuration are successfully synthesized for the first time, within which tetrahedrally coordinated Al sites are preserved. An acidic characterization is used to confirm that the acidity of the Brønsted acid sites is enhanced by the introduction of the Sn species; as a result, the sample exhibits excellent activity in DME carbonylation reaction. Kinetic and DFT studies reveal that this strengthened acidity facilitates the adsorption of DME and reduces the activation barriers of DME dissociation and acetyl formation, accounting for the improved activity. The work demonstrates mechanistic insights into the promoting effects of strong acidity on DME carbonylation and offers a promising strategy to precisely control the acidic strength of zeolites.

Insights into the Structural Evolution Process of Na/ZnFe2O4 Spinel Catalyst in CO2 Hydrogenation

AbstractThe CO2 hydrogenation to olefins process over Fe‐based catalysts offer a promising route for the production of high‐value chemicals from non‐fossil route. Herein, we present a Na promoted ZnFe2O4 spinel catalyst and their structural evolution from fresh state to reduction and to reaction period was elucidated. The clear phase segregation between Fe and Zn occurred after reduction/reaction because of crystalline phase transformation in the order of ZnFe2O4→ZnO+Fe7C3+χ‐Fe5C2→FeO+ZnO+Fe7C3+χ‐Fe5C2. The formation of iron carbide phases (Fe7C3 and χ‐Fe5C2) was enhanced dramatically by Na promoter. The adjacent Na promoter increase the electron density in Fe−Zn interfaces and enhance its ability to dissociate CO* to form adsorbed CHx* species, thus promoting the formation of olefins. This Na promoted rich electronic Fe−Zn interfaces alters the balance between iron oxides and iron carbides on the catalyst surface, which accelerate the chain growth reaction and facilitate the coupling efficiency of tandem reaction. The various catalysts were characterized by N2 physisorption, SEM, HR‐TEM, HAADF‐STEM, ex‐situ /in situ XRD, Mössbauer spectra, ICP, in situ XPS, and operando DRIFTs.

Improving the high-temperature performance by constructing restricted amorphous regions in PEEK

Improving the high-temperature performance of polymers through crosslinking without compromising properties such as ductility and processability remains a significant challenge. In this study, we synthesize a cross-linkable poly (ether ether ketone) end-capped with phenylethynyl groups (PEEK-PEPs) and subsequently melt-blended it with semi-crystalline PEEK to create the PEEK alloy (PEEK/PEEK-PEPs). Under thermal treatment, the curing process of PEEK-PEPs is dominated by the formation of a cross-linked network, accompanied by chain growth reactions. The chain growth reaction will gradually become the dominant reaction as the treatment time increases. These results are validated by successive self-nucleation and annealing, as well as measurements of gel fraction and viscosity before and after thermal treatment. With this approach, the storage modulus (E') of PEEK/PEEK-PEPs is improved by 95 % at 290 °C, and the heat deflection temperature (HDT) is increased by 25 °C. Meanwhile, the tensile strength of PEEK/PEEK-PEPs at room temperature and 150 °C increases to 125 MPa and 72 MPa, respectively, which is 30 % and 31 % higher than that of pristine PEEK resins, while the strain at break remains at the same level as PEEK. These findings potentially provide an advanced polymer alloy preparation method for high-temperature applications, particularly in extreme environments.

Methane-assisted selective bio-oil deoxygenation for high-quality renewable fuel production: A rational catalyst design and mechanistic study

Methane is the main component of naturally abundant natural gas resources and is under-utilized. Bio-oil is a promising energy source with lower economic and environmental costs compared to fossil fuels. However, pyrolysis-derived bio-oil obtained from lipid sources is hindered by high oxygen content and unsaturated species. In this work, an Ir-Ga-Ce/TiO2-A catalyst is theorized and subsequently tailored to optimize deoxygenation product oil quality. After synthesis, 2-hexyl-1-decanol is employed as a model compound to understand the mechanism of deoxygenation under different atmospheres and rationalize the assistance of methane compared to inerts. It is found that methane significantly facilitates the deoxygenation and chain growth reactions by direct incorporation into the paraffinic and naphthenic liquid-phase products. In the gas-phase products, isotopic labeling studies reveal that methane is directly involved with deoxygenation as a major contributor to CO2, and potentially CO. The role of each catalyst component (Ir, Ga, Ce, and TiO2-A) is elucidated, resulting in a sophisticated network tailored for deoxygenation of alcohols with the assistance of methane. The Ir-Ga-Ce/TiO2-A catalyst is then subject to testing on a real pyrolysis-derived bio-oil and shows 84.7% deoxygenation, 0.07% water content by weight, 0.2 (mg KOH g−1) TAN and greater than 1.5% methane conversion, while maintaining the product oil’s structural integrity as a renewable fuel. This work illustrates the potential of a methane-assisted deoxygenation process and explains multiple roles methane can play in achieving better reaction performance and product quality. The effective utilization of methane for bio-oil deoxygenation demonstrates unique benefits for the natural gas and fatty waste industries.

Copolymerization of butadiene and styrene under the influence of n-butyllithium

It is known that styrene-butadiene copolymers having an increased content of 1,2-links of butadiene give tires a unique combination of good grip properties and low rolling resistance. Under conditions of severe operation, heat generation, and, therefore, rolling resistance of this rubber turned out to be less than that of polymers with a conventional structure. Compared to other rubbers, SSBR rubber with a high content of carbon black (mire than 50%) is highly economical. Lower heat generation in SSBR tires is a significant advantage over other rubbers and is preferable for long-term safety of the run even in desert conditions. The growing requirements for energy saving, safety of road transport, ecology, as well as a sufficient level of scientific research in the field of ionic polymerization of monomers were prerequisites for the creation of technology for obtaining solution copolymers based on dienes and vinyl aromatic monomers with special properties based on the mathematical model of the isothermal process of copolymerization of styrene and butadiene in an aliphatic solvent on the n-BuLi/mod catalytic system, which includes four chain growth reactions, two chain transfer reactions to a transfer agent, the concentration of which is recalculated. The calculation of the copolymerization constants of styrene and butadiene in hexane in the presence of the tested catalytic system is presented and the parameters of the obtained mathematical model are determined. Compliance with the optimal mode of conducting the polymerization process makes it possible to obtain rubber with specified physical and mechanical properties. The models presented in this paper take into account the most complex mechanisms of the copolymerization process, taking into account the hydrodynamics and heat transfer in the system, as well as the features of the real technological process. For the first time, the universal approach to solving the problem of obtaining SSBR rubber with a predictable set of properties is proposed. Based on mathematical modeling, laboratory experiments and optimization of the copolymerization process, the possibility of directed synthesis of functionalized DSSC rubber with the required physical and mechanical characteristics has appeared.

Facile preparation of epoxidized soybean oil-hexanediamine resin for fabrication of pressure-sensitive adhesives

Due to the massive consumption of petroleum-derived resources, it is imperative to develop biomass adhesives to replace traditional petroleum-derived materials. The current work deals with the possibility to undergo crosslinking of epoxidized soybean oil (ESO) using hexanediamine (HDA) via one-pot method to produce a pressure-sensitive adhesive, poly(epoxidized soybean oil)-hexanediamine (PESH). The chain growth reaction between ESO and HAD involved the ester group in ESO be destroyed via aminolysis, as evidenced by Fourier Transform Infrared Spectroscopy (FTIR) and 1H Nuclear Magnetic Resonance (1H NMR). The bonding properties of PESH pressure-sensitive adhesive were studied by rolling ball method, shear strength and 180° peeling. The results revealed that the initial viscosity, adhesion persistence and peeling were significantly improved when the molar ratio of ESO to HDA was 1:3. At the same time, the PESH adhesive exhibited good bonding performance under water, especially with PVC substrates, in which the underwater bonding strength can reach 1043 KPa. In addition, PESH adhesive with high crosslinking degree presented excellent resistivity at high voltage. It can be implied that the addition of HDA can acquire the PSA antifungal action. All the results support that at a molar ratio of ESO to HDA of 1:3, it is easier to produce robust crosslinked network structure with overall upgraded properties. Conclusively, the developed PESH adhesive can provide a good application prospect in packaging and insulating fields.

Hydrocarbon Products Occluded within Zeolite Micropores Impose Transport Barriers that Regulate Brønsted Acid-Catalyzed Propene Oligomerization.

Brønsted acid zeolites catalyze alkene oligomerization to heavier hydrocarbon products of varied size and branching. Propene dimerization rates decrease monotonically with increasing crystallite size for MFI zeolites synthesized with fixed H+-site density, revealing the strong influence of intrazeolite transport limitations on measured rates, which has gone unrecognized in previous studies. Transient changes in dimerization rates upon step-changes in reactant pressure (150-470 kPa C3H6) or temperature (483-523 K) reveal that intrazeolite diffusion limitations become more severe under reaction conditions that favor the formation of heavier products. Together with effectiveness factor formalisms, these data reveal that product and reactant diffusion, and consequently oligomerization rates and selectivity, are governed by the composition of hydrocarbon products that accumulate within zeolitic micropores during alkene oligomerization. This occluded organic phase strongly influences rates and selectivities of alkene oligomerization on medium-pore zeolites (MFI, MEL, TON). Recognizing the coupled influences of kinetic factors and intrazeolite transport limitations imposed by occluded reaction products provides opportunities to competently tailor rates and selectivity in alkene oligomerization and other molecular chain-growth reactions through judicious selection of zeolite topology and reaction conditions.

Spatially controlling the mechanical properties of 3D printed objects by dual-wavelength vat photopolymerization

To date, the 3D printing of polymers with heterogeneous and locally controlled material properties is still a challenging area in additive manufacturing. In terms of vat photopolymerization 3D printing, the fabrication of multi-material objects typically relies on an automatic material exchange of different resin vats. However, along with the high complexity of the printing equipment, this technique suffers from a low build speed and often yields 3D printed objects with week interlayer adhesion across the various material interfaces. Herein, we use chemo-selective wavelengths to fabricate objects with multi-material properties by dual-wavelength vat photopolymerization 3D printing employing a single vat. The photopolymers’ stiffness and flexibility are conveniently controlled by two photoreactions working at two different wavelengths. In particular, a dual photocurable resin is applied containing multi-functional acrylates, which are cured by a radical induced chain growth reaction at 405 nm, and bi-functional epoxy monomers, which additionally undergo cationic curing upon UV exposure (365 nm). FT-IR experiments confirm the wavelength selective network formation whilst dynamic mechanical analysis and tensile tests give evidence of the distinctive difference of the related mechanical properties. By being able to produce soft (ε = 24%, σ = 1.0 MPa) and stiff (ε = 4%, σ = 39.1 MPa) networks with a single resin vat, we demonstrate the efficient fabrication of 3D structures with locally controlled mechanical properties using a dual-wavelength 3D printer operating at 405 and 365 nm. In contrast to previous work in this field, we were able to significantly expand the range of mechanical properties by appropriate selection of the acrylic components and to drastically accelerate the build speed by changing the cationic photoinitiator and using a customized printer with high intensity LED sources.

Effect of microcrystalline cellulose on the preparation and performance of rigid polyurethane foam

In order to study the effect of microcrystalline cellulose on the reaction kinetics of polyurethane, in this work, the multi-scale microcrystalline cellulose was added to the foaming system of multifunctional polyether and multifunctional MDI polyurethane. While the chemical reaction was carried out, it was found through in situ FTIR combined with in situ rheological analysis that what was different from the usual inorganic fillers, the hydroxyl on the surface of the microcrystalline cellulose could preferentially react with MDI to generate urethane under the action of the catalyst. In the initial 5–6 min of the reaction, the reaction of soft segment chain growth was the main reaction. Then the main reaction quickly converted to the cross-linking reaction, which greatly increased the viscosity of the system. The addition of microcrystalline celluloses accelerated the improvement of the cross-linking degree and viscosity of the system. The higher the surface hydroxyl content of microcrystalline cellulose, the more significant this trend become. In addition, although the amount of microcrystalline cellulose added was different, the ratio of the reaction rate of the isocyanate group with the hydroxyl group and the amine group eventually tended to be constant, which indicated that there was a stable reactivity rate in the gradual addition reaction during the cross-linking reaction. Combined with SEM analysis, it was found that 25–60 μm microcrystalline cellulose with large hydroxyl content could act as a nucleating agent when the addition amount was less than 0.1%, which was beneficial to increase the cell density and reduce the pore size and improved the impact performance of the foam. The microcrystalline cellulose with a length of more than 90 μm continuously penetrated through several cell walls and destroyed integrity of the cell structure, which would consequently reduce the impact strength of the foam. This paper provided theoretical guidance for polyurethane modified by microcrystalline cellulose.

Study on Microwave Curing of Unsaturated Polyester Resin and Its Composites Containing Calcium Carbonate.

Microwave curing technology has been widely used in resin and its composite materials. In order to study its effect for curing unsaturated polyester resin (UPR) composites containing calcium carbonate (CaCO3) filler, this paper first investigated the influence of microwave power and microwave irradiation time on the curing characteristics of UPR. Then, CaCO3 particles were added to the UPR to investigate the microwave curing effect of the UPR composites containing the CaCO3. The results showed that microwave irradiation could heat the UPR sample evenly, and rapidly cause the chain growth reaction, thus greatly shortening the curing time. The curing degree and products of the samples after microwave curing were consistent with that of the thermal curing. The addition of CaCO3 particles could increase the heating rate of the UPR composites, which would accelerate the curing rate of the UPR. However, higher microwave power could lead to pore defects inside the UPR composites with higher CaCO3 content, resulting in a lower strength. Thus, the compactness of the samples should be improved by reducing the microwave power and prolonging the microwave treatment time.

Toughening Poly(l-lactide) Blends: Effectiveness of Sequence-Controlled Six-Arm Star-Branched Block Copolymers of Poly(l-lactide) and Poly(ε-caprolactone).

Well-defined six-arm star-branched bio-degradable block copolymers of l-lactide and ε-caprolactone were prepared using controlled ring-opening polymerization and a sequential monomer addition method using dipentaerythritol as the initiator core and organocatalysts at low temperatures in solution. Sequence of enchainment was changed by reversing the order of monomer addition giving, either, a crystalline PLA block or an amorphous PCL block as the outer segment. Well-defined six-arm poly(ε-caprolactone-b-l-lactide, 6s-PCL-b-PLA) block copolymers were obtained with a range of segment molecular weights. However, in the case of six-arm poly(l-lactide-b-ε-caprolactone, 6s-PLA-b-PCL), disruption of the block structure was observed on account of competing transesterification reactions accompanying a chain-growth reaction. Such sequence-controlled block copolymers showed interesting phase morphologies, as evidenced by differential scanning calorimetry (DSC) studies. 6s-PCL-b-PLA showed two glass-transition temperatures and two melting temperatures characteristic of the amorphous and crystalline blocks. 6s-PCL-b-PLA and 6s-PLA-b-PCL with different segment chain lengths were solution blended (10 wt %) with a commercially sourced PLA. All the blends were highly transparent. The structure and properties of the blend were examined by DSC, measurement of mechanical properties, and scanning electron microscopy. The results show that a phase-separated 6s-PCL-b-PLA copolymer results in two- to three-fold improvement in tensile toughness without the loss of modulus. A possible hypothesis for the mechanism of tensile toughness in the blend has been proposed.

Reactivity of short radicals at the initial stages of radical polymerization of allyl chloride: Chain growth versus addition to fullerene

AbstractA quantum‐chemical study of the C60 interaction with various radicals generated from monomers in radical polymerization is significant in the fundamental aspects. However, the interactions between fullerene and radicals formed from allyl monomers has been poorly studied. Using the modern density functional theory methods, we performed quantum‐chemical simulation on the C60 interaction with the radicals arising upon the initial stages of the allyl chloride polymerization. We have found that the addition of growth radicals (with 1–4 monomer units) to C60 are more favorable than the chain growth reactions. Herewith, the radicals with 2–4 monomer units are most reactive in the addition reaction. Our quantum‐chemical findings explain the features of the initial stages of the allyl chloride radical polymerization in the presence of C60, namely, the increasing inhibition degree of the radical copolymerization of allyl chloride with methyl methacrylate and increasing induction period of copolymerization with styrene.

A Guideline for the Synthesis of Amino-Acid-Functionalized Monomers and Their Polymerizations.

Amino acids have emerged as a sustainable source for the design of functional polymers. Besides their wide availability, especially their high degree of biocompatibility makes them appealing for a broad range of applications in the biomedical research field. In addition to these favorable characteristics, the versatility of reactive functional groups in amino acids (i.e., carboxylic acids, amines, thiols, and hydroxyl groups) makes them suitable starting materials for various polymerization approaches, which include step- and chain-growth reactions. This review aims to provide an overview of strategies to incorporate amino acids into polymers. To this end, it focuses on the preparation of polymerizable monomers from amino acids, which yield main chain or side chain-functionalized polymers. Furthermore, postpolymerization modification approaches for polymer side chain functionalization are discussed. Amino acids are presented as a versatile platform for the development of polymers with tailored properties.

Kinetic modeling of Fischer–Tropsch‐to‐olefins process via advanced optimization

AbstractThe reaction kinetics of a Fischer–Tropsch (FT) process to produce lower olefins was modeled utilizing the experimental data produced using an in‐house synthesized iron‐based catalyst. Along with FT chain growth reaction that is assumed to follow alkyl mechanism, water–gas shift reaction was also taken into consideration due to its significance. Not only the rate constants but also apparent activation energies were obtained via an integrated approach utilizing multiobjective and constrained nonlinear minimization methods in order to define a model valid at a temperature range instead of a single point. The adaption of a hybrid optimization method utilizing both population‐ and individual‐based techniques enhanced prediction accuracy compared with the case where only multiobjective genetic algorithm is used. Thanks to the developed model, the effect of process parameters on product distribution was investigated. Finally, the kinetic model was compared with Anderson–Schulz–Flory model and the deviations observed were discussed.

Conversion of syngas to triptane-rich liquid hydrocarbons via oxygenates

The triptane-rich liquid hydrocarbons are produced from syngas via oxygenates in two stages: in the first stage the oxygenates (methanol and dimethyl ether) are formed from CO + H2 over the Cu-Zn-Al-catalyst; in the second stage the oxygenates are converted to triptane-rich liquid hydrocarbons over the combined Mg-HZSM-5/Pd-La-HY catalyst. Over the Mg-HZSM-5, light olefins are formed in high yield, while the formation of triptane occurs over the Pd-La-HY, which is active in the isomerization of aliphatic hydrocarbons and in the alkylation of light iso-paraffins with light olefins. The increased water content in the reaction zone was found to lead to an increase in the yield of gaseous products. Water acts as an inhibitor of chain growth and methylation reactions and leads to the accumulation of methanol in the condensate. For efficient and stable (more than 72 h) operation of Mg-HZSM-5/Pd-La-HY, the concentration of water in the feedstock should not exceed 10 wt. %.

Kinetics of ethylene oligomerization over Ni-H-Beta catalysts

We report the kinetics of ethylene oligomerization over the Ni-H-Beta for temperatures ranging between 50 and 100 °C and pressures ranging between 5 and 28 atm. According to our results, the apparent activation energies involved in the formation of butene, hexene, and octene are 44, 78, and 60 kJ.mol−1, respectively. The measured lower apparent activation energy for butene formation relative to hexene and octene is a likely result of the fact that the measured butene formation is not the true (forward) rate of formation of butene but it the net rate because of the consumption of butene in secondary reactions. Analysis of the reaction order indicates that participation of butene in chain-growth reactions takes place via desorption followed by re-adsorption of butene on the catalyst. The results also indicate that hexene undergoes a similar process. In the present paper, we refer to the pathway involving co-oligomerization of butene and hexene as “cascade co-oligomerization”. Based on these findings, we proposed a reaction network and modeled reaction rate expressions for ethylene consumption and butene, hexene, and octene formation based on the construction of a micro-kinetic model. We calculated the kinetic parameters involved in the reaction network proposed and found evidence that the formation of octene proceeds mainly via the “cascade co-oligomerization” of re-adsorbed butene with ethylene.

Insight into the role of Co2C supported on reduced graphene oxide in Fischer-Tropsch synthesis and ethene hydroformylation

The roles of Co2C supported on reduced graphene oxide (RGO) for both Fischer-Troprsch (FT) and ethene hydroformylation reactions have been studied for the first time. Two catalysts, cobalt supported by RGO (CG) and Rh promoted cobalt supported by RGO (RCG), have been successfully synthesized. A series of experiments were performed where the feed was switched between syngas and a syngas–ethene mixture. During H2 reduction: Metallic Co has been formed for the CG catalyst; However, Co2C was detected in RCG catalyst, which experimentally proved that the RGO was the carbon source for the formation of Co2C. After H2 reduction, both CG and RCG catalyst exhibited extremely low FT reactivity, which indicated that the interaction between the Co and RGO limited the FT chain growth reaction. The catalyst characterization results proved that the exposure of the CG and RCG catalysts to syngas or/and a syngas-ethene mixture could transform CoO or/and metallic Co to Co2C. It was found that the Co-Co2C interface derived from CG catalyst was inactive for FTS and exhibited low CO conversion with the main products being short chain alcohols and hydrocarbons (C1-C4). Nevertheless, exposing the Co-Co2C interface to CO/C2H4/H2 feed promoted the production of C3 oxygenates, which indicated the multi-phase of Co-Co2C was highly active for ethene hydroformylation. Moreover, a pure Co2C phase was obtained with the promotion of Rh, which was completely inactive for FTS but highly active for ethene hydroformylation. It is can be concluded that the interaction between RGO and cobalt species could suppress CO chain growth reaction, while promoting the CO insertion reaction to form aldehydes or alcohols.