Physical mixing of a catalyst and a hydrophobic polymer promotes CO hydrogenation through dehydration

Abstract

In many reactions restricted by water, selective removal of water from the reaction system is critical and usually requires a membrane reactor. We found that a simple physical mixture of hydrophobic poly(divinylbenzene) with cobalt-manganese carbide could modulate a local environment of catalysts for rapidly shipping water product in syngas conversion. We were able to shift the water-sorption equilibrium on the catalyst surface, leading to a greater proportion of free surface that in turn raised the rate of syngas conversion by nearly a factor of 2. The carbon monoxide conversion reached 63.5%, and 71.4% of the hydrocarbon products were light olefins at 250°C, outperforming poly(divinylbenzene)-free catalyst under equivalent reaction conditions. The physically mixed CoMn carbide/poly(divinylbenzene) catalyst was durable in the continuous test for 120 hours.

Advances in Selectivity Control for Fischer–Tropsch Synthesis to Fuels and Chemicals with High Carbon Efficiency

“…One route is based on bifunctional catalysis using oxide–zeolite composite catalyst (OX-ZEO), where the activation of CO and the C–C bond formation are performed on separated active sites. ,,, Therefore, the product selectivity can be facilely controlled, and the selectivity to lower olefins in hydrocarbons reaches up to ∼80%, surpassing the maximum value predicated by the ASF model. Fischer–Tropsch to olefins (FTO) is another promising direct route for olefin production from syngas. ,,,,, Although the selectivity to lower olefins is limited by the ASF model, the FTO process is highly efficient for long-chain olefin production, and a higher CO conversion as well as olefin yield can be readily obtained. The typical FTO catalysts include Fe-based and Co-based systems …”

“…Fischer−Tropsch to olefins (FTO) is another promising direct route for olefin production from syngas. 16,23,24,83,88,89 Although the selectivity to lower olefins is limited by the ASF model, the FTO process is highly efficient for long-chain olefin production, and a higher CO conversion as well as olefin yield can be readily obtained. The typical FTO catalysts include Fe-based and Co-based systems.…”

Microenvironment engineering of supported metal nanoparticles for chemoselective hydrogenation

“…The authors interpreted this observation to the entropic stabilization of a product-like intermediate by the Lewis acid interaction of these species with the amino groups of polymer layers. More recently, Xiao, Wang, Zheng and co-workers reported that the physical mixture of CoMnC catalysts and a hydrophobic polymer greatly promoted CO hydrogenation activity through fast removal of generated H 2 O 132.…”

Liquid–Liquid–Solid Triphase Interface Microenvironment Mediates Efficient Photocatalysis

“…The interfacial microenvironment around the catalyst is often the determining factor to the reaction performance − because it affects the diffusion of reactants and products, the local pH value, and the number of active sites, and then significantly influences the catalytic process and/or kinetics. − For example, by enhancing the hydrophobicity of catalysts, the interface microenvironment can be tuned from a liquid–solid diphase into a gas–liquid–solid triphase, which leads to a much-increased interface concentration of gaseous reactants and kinetics of photocatalytic, enzymatic, and electrocatalytic reactions. − Similarly, by enhancing the hydrophilicity (aerophobicity) of catalysts, the adhesion of gaseous product on the electrode surface can be greatly reduced, which allows more active sites to be exposed and leads to a much-enhanced gas-born electrocatalytic reaction. − Very recently, modulation of the local environment via the physical mixing of catalysts and a hydrophobic polymer was found to benefit the rapid shipping of water products from the reaction system and promote CO hydrogenation through dehydration . Therefore, rational design and modulation of reaction interface architecture are an important strategy to boost the catalytic performance without optimizing the catalysts themselves.…”