Synthesis of amino-functionalized amorphous carbon membranes via glucose-solution hydrothermal method

There remains an ever-increasing interest in carbon membranes due to their chemical properties and heat resistance. This study aims to investigate the influence of the amino-functionalization of amorphous carbon membranes on the H2/CO2 separation ability. Amino-functionalized amorphous carbon membranes were synthesized on porous alumina via a hydrothermal method using a glucose solution with added ammonia. The gas permeabilities and other characteristics of the membranes were evaluated. The electron probe microanalyzer (EPMA) results indicate that the carbon was deposited on the surface and inside of the alumina support, and the carbon deposited region inside varied depending on the ammonia concentration. The Fourier-transform infrared spectroscope (FT-IR) analyses suggest that the membranes hydrothermally treated with ammonia solution include nitrogen atoms in the form of functional amino groups. The gas transmission rate (GTR) results indicate that the H2/CO2 gas selectivity for the sample hydrothermally treated with ammonia solution (approximately 12.2) was higher than that of the untreated sample (approximately 4.7).