Boreskov Institute of Catalysis of the Siberian Branch of Russian ...

PP-IV-30PRODUCTION OF CO-FREE HYDROGEN THROUGH SELECTIVECATALYTIC DECOMPOSITION OF PROPANE AND N-BUTANESolov’ev E.A., Kuvshinov D.G., Ermakov D.Yu.*, Kuvshinov G.G.Novosibirsk State Technical University,Karla Marksa Pr-t, 20, Novosibirsk, 630092, Russia*Boreskov Institute of Catalysis,Academic Lavrentiev Pr-t, 5, Novosibirsk, 630090, RussiaFax: +7-383-346-08-01, e-mail: kuvshinov_g@mail.ruHydrogen is an important clean energy source for use in fuel cell. The most promisingfuel cell is considered to be proton exchange membrane fuel cell (PEMFC) [1]. Hydrogen fuelfor PEMFC must not contain СО admixtures, because СО is a poison for catalysts which areused in fuel cells.The most perspective method of production of CO-free hydrogen at present-day iscatalytic decomposition of hydrocarbons. The essence of this process is the following:gaseous hydrocarbons in the presence of catalysts which contain metals of the VIII groupdecompose to mainly H 2 , CH 4 and carbon nanofibers. At that a negligible admixtures ofhydrocarbons С 2 -С 3 [2-3] can appear in products depending on the composition ofhydrocarbon feedstock and conditions of process carrying out. It should be noticed that usingof hydrocarbons heavier than CH 4 as a feedstock such as C 3 H 8 and n-C 4 H 10 allows to carryout the process at much lower temperatures in comparison with CH 4 and also to receivehigher H 2 yields per mass unit of a catalyst during its deactivation. Moreover C 3 H 8 andn-C 4 H 10 catalytic decomposition under certain conditions allows increasing the selectivity ofhydrogen and reducing the concentration of CH 4 in gaseous products almost to the zero-level.This circumstance has a great practical importance due to the fact that H 2 could be easierseparated from C 2 -C 4 hydrocarbons than CH 4 (e.g. by relatively inexpensive membraneseparation).Four types of high-loaded bimetallic catalysts was used: (70 wt.% Ni–20 wt.% Cu)/Al 2 O 3 ,(63 wt.% Ni–24 wt.% Cu)/SiO 2 , (50 wt.% Ni–40 wt.% Cu)/SiO 2 and (40 wt.% Ni–50 wt.%Cu)/SiO 2 . Experiments were carried out in quartz flow reactor with a vibrofluidized bed underatmospheric pressure at 500–700°C. Undiluted C 3 H 8 and n-C 4 H 10 were used. Hydrocarbonflow of 100 L·h –1 per 1 gram of catalyst was maintained by Mass-Flow controller.Experimental investigations have shown that the (50 wt.% Ni–40 wt.% Cu)/SiO 2 catalystexhibited the best activity and selectivity. At 600°C the catalyst provides production ofmixture with more than 30 vol.% of hydrogen concentration (see Fig. 1).448