The equilibrium relationship between the stationary and the mobile phase plays a leading role in chromatography; especially for higher concentrations where the equilibrium relationship becomes nonlinear. Based on local equilibrium theory, a simple numerical algorithm is developed by considering the multicomponent nonlinear equilibrium relationship and its Jacobian matrix to quickly obtain a first prediction of the chromatographic separation without the need of providing mass transfer data. The impact of several favorable multicomponent equilibrium isotherms on chromatographic separations is studied : The multicomponent Langmuir isotherm, a polynomial and an exponential extension of the multicomponent Langmuir isotherm.