  This paper presents our study of the asymptotic behavior of a two-component
system of Brownian motions undergoing certain singular interactions. In
particular, the system is a combination of two different types of particles and
the mechanical properties and interaction parameters depend on the
corresponding type of particles. We prove that the hydrodynamic limit of the
empirical densities of two types is the solution of a certain quasi-linear
parabolic partial differential equation known as the Maxwell-Stefan equation.
