CO <sub>2</sub> hydrogenation to dimethyl ether over In <sub>2</sub> O <sub>3</sub> catalysts supported on aluminosilicate halloysite nanotubes
A. A. Pechenkin, Д. И. Потемкин, С. Д. Бадмаев, E. M. Smirnova, Kirill A. Cherednichenko, В. А. Винокуров, А. P. Glotov
Abstract
Abstract 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.