  Patchy colloidal model with three and four equivalent patches, confined in
the attractive random porous media, undergo re-entrant gas-liquid phase
separation with the possibility for the liquid phase density to approach zero.
This unusual behavior is caused by an interplay between strong fluid-fluid
bonding interactions and weak fluid-matrix attractions. At high temperature the
shape of the phase diagram is determined by the attractive interaction between
the fluid particles; weak Yukawa attraction between fluid and obstacles only
slightly enhances the fluid-fluid bonding. At low enough temperature the
network of the fluid particles is formed and the shape of the phase diagram
becomes defined by the Yukawa fluid-obstacle attraction. Due to this
interaction a layer of mutually bonded particles around the obstacles is formed
and the network becomes fluid particles in the network is defined by a spatial
arrangement of the matrix particles. These features may open a new
possibilities in making the equilibrium gels with the predefined nonuniform
distribution of the particles.
