Hybrid membrane catalytic process for the hydrogenation of nitroaromatic compounds and simultaneous production of aromatic amines

• A new, hybrid, passive, flow independent remediation via catalysis-dialysis is presented. • Re-loaded anion exchange membranes enable dialysis-driven reduction of nitroaromatics. • Simultaneous catalytic conversion and separation of aromatic amines is achieved. • Membrane-catalyst integrates reaction and transport in one continuous system. • Catalytic performance is tuned by membrane characteristics. In the paper presented, a hybrid process that combines the catalytical hydrogenation of nitroaromatic compounds (NACs) and the membrane separation using Donnan dialysis (DD) was studied. Four membranes used were composed with the interpolymer network (IPN) of polyethylene and poly(styrene-co-divinylbenzene), additionally functionalized with aliphatic or aromatic amines, and incorporating rhenium (Re) active sites. The proposed process was used for the conversion of selected nitroaromatics (NACs): 2-nitroaniline (2-NA), 4-nitroaniline (4-NA), 2,4,6,-trinitrophenol (2,4,6,-TNP) and nitrobenzene (NB). The offered process ensured simultaneous NACs hydrogenation and separation of the obtained aromatic amines (AAs) with the high molecular-level purity of the reaction product without residual NACs in the concentrate solution. For the analysis of reaction, the pseudo first-order model was used, the values rate constants ( k 1 ) for the reaction were dependent on the type of feed solution and the membrane used. The highest value of this parameter reached 10.6 × 10 −2 min −1 for 2-NA, and the membrane functionalized with bis-3-aminopropylamine containing Re active sites. Besides catalytic reduction, this membrane enables effective separation of 50 % of resultant 1,2-diaminobenzene.