In the control of chemical reactors, it is important to know the kinetic parameters of the reaction with good precision. The traditional approach is to try to estimate them from laboratory experiments or from plant records, where variations due to control or to disturbances may occur. However, this may happen only sporadically in the plant history because the reactor is at steady state for long periods of time. It would be advantageous to experiment online, so that the estimation of the kinetic parameters could be made more accurately and independently of plant changes.