In reactive distillation the design has to specify the rate of reactio
n on each stage. This can be done either in one design phase using ''g
lobal optimization'' or stage by stage using ''local optimization'' on
each stage. A design algorithm and a design program for such a ''loca
l optimization'' approach for reactive distillation is presented. The
optimization is based on directions in the concentration space. A desi
gn example is presented.