\documentclass[tikz]{standalone}

\definecolor{ice2}{RGB}{8,81,156}
\definecolor{liq2}{RGB}{66,146,198}

\begin{document}

\begin{tikzpicture}
    \draw[->,thick] (-0.5,0) -- (9,0) node[right] {$1/\rho$};
    \draw[->,thick] (0,-0.5) -- (0,5.5) node[above] {$p(T,\rho)$};

    \begin{scope}[scale=1.8]
        \fill[liq2, opacity=0.5] 
            (0.604,0.64) -- 
            plot[domain=0.604:2.403, smooth, samples=100] (\x, {7.2/(3*\x-1)-3/(\x^2)}) -- 
            (2.403,0.64) -- cycle;
        \begin{scope}
            \clip (0, 0) rectangle (5,3);
            \draw[thick, domain=0.4:4.5, smooth,samples=100] plot (\x, {9/(3*\x-1)-3/(\x^2)});
            \draw[ice2,thick, domain=0.4:4.5, smooth,samples=100] plot (\x, {8/(3*\x-1)-3/(\x^2)});
            \draw[thick, domain=0.4:4.5, smooth,samples=100] plot (\x, {7.2/(3*\x-1)-3/(\x^2)});
        \end{scope}
        \node[above] at (4,0.7) {$T>T_c$};
        \node[ice2,right] at (4.5,0.5) {$T=T_c$};
        \node[above] at (4,0.1) {$T<T_c$};
        \draw[dashed,thick] (0.604,0.64) -- (2.403,0.64);
    
        \draw[dotted,thick] (0.604,0.64) -- (0.604,0) node[below] {$1/\rho_{\mathrm{liq}}$};
        \draw[dotted,thick] (2.403,0.64) -- (2.403,0) node[below] {$1/\rho_{\mathrm{vap}}$};
    \end{scope}
\end{tikzpicture}

\end{document}