  Phase separation and criticality are analyzed in $z$:1 charge-asymmetric
ionic fluids of equisized hard spheres by generalizing the Debye-H\"{u}ckel
approach combined with ionic association, cluster solvation by charged ions,
and hard-core interactions, following lines developed by Fisher and Levin
(1993, 1996) for the 1:1 case (i.e., the restricted primitive model). Explicit
analytical calculations for 2:1 and 3:1 systems account for ionic association
into dimers, trimers, and tetramers and subsequent multipolar cluster
solvation. The reduced critical temperatures, $T_c^*$ (normalized by $z$),
\textit{decrease} with charge asymmetry, while the critical densities
\textit{increase} rapidly with $z$. The results compare favorably with
simulations and represent a distinct improvement over all current theories such
as the MSA, SPB, etc. For $z$$\ne$1, the interphase Galvani (or absolute
electrostatic) potential difference, $\Delta \phi(T)$, between coexisting
liquid and vapor phases is calculated and found to vanish as $|T-T_c|^\beta$
when $T\to T_c-$ with, since our approximations are classical, $\beta={1/2}$.
Above $T_c$, the compressibility maxima and so-called $k$-inflection loci
(which aid the fast and accurate determination of the critical parameters) are
found to exhibit a strong $z$-dependence.
