A one-dimensional column is considered i n which a number of chemical reactions with arbitrary kinetics may take place among an arbitrary number of components. initially, the column is i n complete chemical and physical equilibrium. A localized small p e r t u r b t i o n is introduced i n the column a t time t = 0. It i s shown that, i n general, this initial perturbation separates into a definite number of peaks which move with different velocities. Each peak broadens according t o an asymptotic relation, depending on a characteristic dispersion coefficient. I f n is the number of components, m the number of independent reactions, and u the number of equations of state t o be considered, there are n-m-u peaks. These peaks do not correspond t o single substances as in classical chromatography, but each peak has an eigencomposition. The velocities of the peaks are derived as functions of stoichiometry and equilibrium data. The dispersion coefficients depend, i n addition, on the kinetics of the chemical reactions and on the rate of mass transfer. Thus, perturbation chromatography offers a means of determining both equilibrium and rate data. The theory is illustrated by means of two examples.The term perturbation chromatography used in the title of this paper covers a broader class of phenomena than is normally associated with chromatography. A definition will now be given which, at the same time, delimits the scope of this work. Consider the steady flow of a multicomponent fluid over a uniformly distributed fixed adsorbent-catalyst phase. In the initial steady state condition, fluid composition is independent of position and time and determines the concentrations in the fixed phase through various physical and chemical equilibrium relations. At some time zero, the system is perturbed over a small portion of its length by a small change in composition of one of the phases. Perturbation chromatography is the behavior of the system after time zero. The description and use of the set of disturbances which propagates downstream is considered here.Earlier work in this area is summarized by Collins and Deans ( 2 ) , who discussed the number and velocity of peaks to be expected under ideal, local equilibrium conditions. In the present work, the equilibrium theory is generalized, and chemical and mass transport kinetics are taken into consideration. The behavior of the set of disturbances resulting from the initial perturbation will be related to the equilibrium composition of both phases, the stoichiometry of the reactions taking place, the chemical and physical equilibrium functions, and the interphase transfer and intraphase chemical reaction rates. These relations can be put to practical use in obtaining unknown equilibrium and rate information from observation of pulse behavior.The information to be gained is quite general. In particular, no limitation as to number of components or reactions is necessary; the restriction of infinite dilution Gemot Klauser is with the