Solid-liquid-vapour equilibrium conditions of tetra-iso-amyl ammonium bromide (TiAAB) semiclathrates formed from H2

Abstract

The tetra-iso-amyl ammonium bromide (TiAAB) is synthesized according to Menschutkin's reaction and the fundamental characterization of TiAAB is conducted using ESI mass spectrum and 13C NMR spectra, respectively. Using an isochoric equilibrium cell the H2 semi-clathrates were formed in the presence of three different TiAAB solutions; a 15 wt% solution, a 30 wt% solution, and a 45 wt% solution. Using TiAAB allows for the formation of H2 semi-clathrates at much milder P-T conditions as compared to other quaternary ammonium salts such as TBAB, TBAN, TBPB, and TBAF. The mixed H2/TiAAB semi-clathrates were found to form over a narrow range of temperatures from 303 K to 304 K, and the pressure ranged from atmospheric pressure to above 4 MPa. The experimental results obtained in the current work contribute to developing a method to store hydrogen gas with mixed H2/TiAAB semi-clathrate.