The problem of obtaining motor fuels with improved environmental characteristics corresponding to Euro-4 and Euro-5 standards is examined. The experience of Kedr-89 Scientific-Production Company in revamping of naphtha cut isomerization units is presented. The operating parameters of deisohexanizers developed by Kedr-89 Co. are reported. The possibility of including depentanization and deisopentanization towers in the network of isomerization units is considered.