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Microkinetics simulations are presented based on DFT‐determined elementary reaction steps of the Fischer–Tropsch (FT) reaction. The formation of long‐chain hydrocarbons occurs on stepped Ru surfaces with CH as the inserting monomer, whereas planar Ru only produces methane because of slow CO activation. By varying the metal–carbon and metal–oxygen interaction energy, three reactivity regimes are identified with rates being controlled by CO dissociation, chain‐growth termination, or water removal. Predicted surface coverages are dominated by CO, C, or O, respectively. Optimum FT performance occurs at the interphase of the regimes of limited CO dissociation and chain‐growth termination. Current FT catalysts are suboptimal, as they are limited by CO activation and/or O removal.

The kinetics of synthesis gas conversion on the stepped Rh(211) surface were investigated by computational methods. DFT calculations were performed to determine the reaction energetics for all elementary reaction steps relevant to the conversion of CO into methane, ethylene, ethane, formaldehyde, methanol, acetaldehyde, and ethanol. Microkinetics simulations were carried out based on these first-principles data to predict the CO consumption rate and the product distribution as function of temperature. The elementary reaction steps that control the CO consumption rate and the selectivity were analyzed in detail. Ethanol formation can only occur on the stepped surface, because the barrier for CO dissociation on Rh terraces is too high; step-edges are also required for the coupling reactions. The model predicts that formaldehyde is the dominant product at low temperature, ethanol at intermediate temperature, and methane at high temperature. The preference for ethanol over long hydrocarbon formation is due to the lower barrier for C(H) + CO coupling as compared with the barriers for CH x + CH y coupling reactions. The C(H)CO surface intermediate is hydrogenated to ethanol via a sequence of hydrogenation and dehydrogenation reactions. The simulations show that ethanol formation competes with methane formation at intermediate temperatures. The rate-controlling steps are CO oxidation to create empty sites for the dehydrogenation steps in the reaction sequence leading to ethanol, CH x CH y O hydrogenation for ethanol formation, and CH 2 and CH 3 hydrogenation for methane formation. CO dissociation does not control the overall reaction rate on Rh. The most important reaction steps that control the selectivity of ethanol over methane are CH 2 and CH 3 hydrogenation as well as CHCH 3 dehydrogenation.

MIL‐101, a chromium‐based metal–organic framework, is known for its very large pore size, large surface area and good stability. However, applications of this material in catalysis are still limited. 5‐Hydroxymethylfurfural (HMF) has been considered a renewable chemical platform for the production of liquid fuels and fine chemicals. Phosphotungstic acid, H3PW12O40 (PTA), encapsulated in MIL‐101 is evaluated as a potential catalyst for the selective dehydration of fructose and glucose to 5‐hydroxymethylfurfural. The results demonstrate that PTA/MIL‐101 is effective for HMF production from fructose in DMSO and can be reused. This is the first example of the application of a metal–organic framework in carbohydrate dehydration.