The kinetics of phosgenation of 2-amino-5-naphthol-7-sulfonic acid in alkaline solution has been investigated at 323-353 K. The experiments in a flat contact surface reactor have been carried out, and the model of the reaction has been proposed. Apparent kinetic constants were calculated. The proposed model was verified in the packed absorption column. The predicted concentrations of 5,5＇-dihydroxy-2,2＇-dinaphthylcarbamide-7,7＇-disulfonic acid and 2-amino-5-naphthol-7-sulfonic acid vs column height were compared with the experimental results. The statistical analysis showed a very good agreement between the experimental data and the concentrations obtained from the model.