Synthesis of Amines from Carbon Oxides and Hydrogen with Ammonia Co-Feeding

This study demonstrates the possibility of amines synthesis of wide-boiling-range amines from H 2 /CO x /ammonia mixtures. Using Fe–Co slurry catalysts with an active phase loading of 2 wt %, 58–75% selectivity toward liquid products was achieved. In a single-stage conversion of carbon dioxide mixed with hydrogen the selectivity toward target liquid products did not exceed 40–55%, with high methane selectivity observed as a competing reaction. When studying the efficiency of the intermediate reaction of CO conversion formed from CO 2 , it was found that in the temperature range of 260–300°C the process proceeds with the highest yield of liquid hydrocarbons and amines (41–44 g per cubic meter of syngas) with product selectivity reaching up to 75%. At 30 bar, selectivity toward liquid hydrocarbons and amines was nearly insensitive to feed gas flow rate, suggesting that mass transfer limitations play a significant role under these conditions. The reaction produced amines with carbon numbers up to 17, consisting primarily of 1- and 2-alkylamines. Additionally, N -methylalkylamines and N,N -dimethylalkylamines were formed, presumably via hydrocarbon chain growth resulting from CO incorporation into the N–C bond of surface intermediates.