The aim of this work was to design a reactor for the production of monochloroacetone in the gaseous phase. To obtain a high selectivity and yield of the process, the reactor was proposed as a part of an atmospheric packed rectification column. The principal reactions take place on the feed stage of the column without packing. The recycling of the unconverted acetone was carried out from both the rectifying tin liquid phase) and the stripping sections tin gas phase). The reaction heat was removed by evaporation of the liquid acetone. The simulation of such a column was performed using the simulation program HYSYS. Because of non-standard reaction kinetic expressions, not allowed in the HYSYS program, the reactor had to be described by using fictive streams. The simulation program is very flexible and useful for the simulation and design of this type of column.