The film and the Danckwerts penetration models were used to model the heterogeneous liquid-liquid reaction of benzene nitration. Analytical solutions were developed for both models considering a pseudo-first order reaction. Models were confronted with experimental results showing good predictions in the intermediate reaction regime (0.3 < Ha < 2). Profiles of both models were evaluated confirming similarities and identical approximate behaviours. Therefore, both models seem adequate to model industrial systems operating mostly in this intermediate reaction regime, although the film model allows a simpler mathematical treatment. (C) 2004 Elsevier Ltd. All rights reserved.