The selective synthesis of lower olefins(C2 - C4) by the CO2 hydrogenation over Iron catalysts promoted with Potassium and supported on ion exchanged(H, K) Zeolite-Y

Electrochemical promotion of CO 2 hydrogenation on Ru catalyst–electrodes supported on a K–β″–Al 2 O 3 solid electrolyte

“…The turnover frequency (TOF) of the reaction, in units of s À1 , is computed from the expression TOF ¼ r=N G (14) where r is the catalytic rate expressed in mol/s and N G is the catalyst surface area expressed in mol Ru. From this N G value and the total mol number, N, of Ru in the sample (N = 2Á10 À3 g/101.7 mol/g = 1.97Á10 À5 mol) one computes a dispersion, N G /N, of 0.07.…”

“…The chemical promotion of CO 2 methanation catalysts by alkalis has been investigated by several groups [9,10,[13][14][15]. Kim et al [14] found that the basicity of the catalyst surface is increased by using potassium exchanged Y-zeolite resulting in a significant improvement of the hydrocarbon yield and of the C2-C4 olefins selectivity.…”

“…Kim et al [14] found that the basicity of the catalyst surface is increased by using potassium exchanged Y-zeolite resulting in a significant improvement of the hydrocarbon yield and of the C2-C4 olefins selectivity. On the other hand, hydrogen exchanged Y-zeolite depresses surface basicity resulting in an increased rate of methane production.…”

“…Steady-state effect of catalyst potential and corresponding K + ¼ 7kPa; P CO2 ¼ 1kPa, F v = 100 cm 3 STP/min and on the corresponding Turnover Frequency (TOF) values defined by Eq (14),. i.e.…”

Heterogeneous Catalysis for the Valorization of CO2: Role of Bifunctional Processes in the Production of Chemicals

“…methanol synthesis) or that result in a very wide spectrum of products (Fischer Tropsch like chemistry), over the last few years, the use of cascade thermochemical processes involving multifunctional catalysts or the combination of several catalysts in a single reactor vessel for the valorization of CO2 has gained a lot of attention. More specifically, the use of bifunctional catalysis (a combination of a metal/metal oxide and a zeolite) for the heterogeneous gas phase hydrogenation of CO2 to value added compounds (especially olefins and aromatics) is one of the most attractive technologies [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] . Olefins are key components of the chemical industry, being fundamental building blocks for many different derivatives, while aromatic compounds such as benzene, toluene and xylenes are in the top 20 chemicals produced in the world.…”