Formic acid decomposition to H₂-rich gas was investigated over a CuO-CeO₂/γ-Al₂O₃ catalyst. The catalyst was characterized by XRD, HR TEM and EDX methods. A 100% conversion of formic acid was observed over the copper-ceria catalyst under ambient pressure, at 200–300 °C, N₂:HCOOH = 75:25 vol.% and flow rate 3500–35,000 h⁻¹ with H₂ yield of 98%, wherein outlet CO concentration is below the equilibrium data (<0.5 vol.%). The copper-ceria catalyst proved to be promising for multifuel processor application, and the H₂ generation from dimethoxymethane, methanol, dimethyl ether and formic acid on the same catalyst for fuel cell supply.

This work presents results on CO ₂ hydrogenation to dimethyl ether (DME) over bifunctional catalysts consisting of In ₂ O ₃ , supported on natural clay halloysite nanotubes (HNT), and HNT modified with Al-MCM-41 silica arrays. The catalysts were characterized by TEM, STEM, EDX-mapping, NH ₃ -TPD, XRD, low-temperature nitrogen adsorption, TPO, and H ₂ -TPR techniques. Catalytic properties of In ₂ O ₃ /HNT and In ₂ O ₃ /Al-MCM-41/HNT in the CO ₂ hydrogenation to DME were investigated in a fixed-bed continuous flow stainless steel reactor at 10–40 atm, in the temperature range of 200–300°C, at GHSV = 12,000 h ⁻¹ and molar ratio of H ₂ :CO ₂ = 3:1. The best catalyst for CO ₂ hydrogenation was In ₂ O ₃ /Al-MCM-41/HNT that provided DME production rate 0.15 g _DME ·(g _cat ·h) ⁻¹ with DME selectivity 53% and at 40 bar, GHSV = 12,000 h ⁻¹ , and T = 250°C. It was shown that In ₂ O ₃ /Al-MCM-41/HNT exhibited stable operation for at least 40 h on stream.

The performance of a СuO–ZnO/γ-Al2O3catalyst for the reactions of methanol, dimethyl ether (DME) and dimethoxymethane (DMM) steam reforming (SR) to hydrogen-rich gas was studied. The catalyst was...

Hydrogenation of CO₂ relative to valuable chemical compounds such as methanol or dimethyl ether (DME) is an attractive route for reducing CO₂ emissions in the atmosphere. In the present work, the hydrogenation of CO₂ into DME over CuO-In₂O₃, supported on halloysite nanotubes (HNT) was investigated in the temperature range 200–300 °C at 40 atm. HNT appears to be novel promising support for bifunctional catalysts due to its thermal stability and the presence of acidic sites on its surface. CuO-In₂O₃/HNT catalysts demonstrate higher CO₂ conversion and DME selectivity compared to non-indium CuO/HNT catalysts. The catalysts were investigated by N₂ adsorption, X-ray diffraction, hydrogen-temperature programmed reduction and transition electron microscopy. The acid sites were analyzed by temperature programmed desorption of ammonia. It was shown that CuO/HNT was unstable under reaction conditions in contrast to CuO-In₂O₃/HNT. The best CuO-In₂O₃/HNT catalyst provided CO₂ conversion of 7.6% with 65% DME selectivity under P = 40 atm, T = 250 °C, gas hour space velocity 12,000 h⁻¹ and H₂:CO₂ = 3:1.

The data obtained for the first time on the influence of the sequence of metal deposition and the conditions of formation of the Re-containing component on the properties of a series of catalysts 1.9 wt % Pt–1.8 wt % Re/Ce_0.75Zr_0.25O₂ in the water gas shift reaction are presented. It is shown that catalysts in which platinum is deposited first have a content of both metals close to the expected level and make it possible to achieve the maximum CO conversion at a lower temperature compared to a monometallic platinum catalyst. Based on the data on CO chemisorption and calculations of the reaction rate per platinum surface area, it is assumed that the role of the Re-containing phase is to a greater degree related to the stabilization of a highly dispersed platinum state, rather than to participation in the catalysis of the reaction.