Hydrogen sorption in transition metal modified ETS-10

Abstract

Hydrogen adsorption studies in nickel, rhodium and palladium exchanged and in situ loaded titanosilicate ETS-10 were performed at 77.4 K using a static volumetric adsorption system up to 1 bar, and 303 K in a gravimetric adsorption system up to 5 bar. The hydrogen adsorption isotherms at 77.4 K were reversible with pressure but chemisorption of hydrogen was noticed at 303 K. Rhodium exchanged ETS-10 showed the highest hydrogen adsorption capacity of 82.6 cc/g at 77.4 K. The hydrogen adsorption isotherm analysis at 303 K was repeated up to three adsorption runs to check the repeatability of hydrogen uptake. At 303 K palladium loaded ETS-10 showed the highest hydrogen uptake capacity of 33.1 cc/g. The DRIFT spectra analysis of ETS-10 samples before and after hydrogen adsorption was conducted, which confirmed that the hydrogen adsorbed in transition metal modified ETS-10 at 303 K was due to the chemical interactions in the form of transition metal hydrides inside ETS-10. The absorbed hydrogen at 303 K can be desorbed by heating the ETS-10 sample up to 413 K.