  We study the phase diagram of the spin-3/2 Blume-Emery-Griffiths model on a
honeycomb lattice by Monte Carlo simulations in order to verify the presence of
some peculiar features predicted by the effective field theory (EFT) with
correlations. The locations of the order-disorder phase boundaries are
estimated from thermal variations of the magnetic susceptibility curves. It is
found that for positive values of the biquadratic interactions the critical
boundary shows a discontinuous character as a function of the single-ion
anisotropy strength, in line with the EFT expectations. However, for negative
values of the biquadratic interactions the step-like variation of the critical
frontier predicted by EFT was not reproduced.
