Make “#+BEGIN_EXPORT latex” also exported to html (orgmode)

Question

I know that placing latex code in the main text body solve my issue: the latex code is taken into account both when exporting to latex and to html. However, I like to use Latex blocks because of the syntax highlighting (usefull for long equations etc.).

Does anyone knows a way to make this block also treated by MathJax when exported throught org-export:

#+begin_export latex
\begin{equation}
\left\{
    \begin{array}{ll}
        \dfrac{\partial C(x, t)}{\partial t} = \vec{\nabla} \cdot \left( D(x)\vec{\nabla} C(x,t) \right) 
        \quad \forall x\in\Omega \\
        \dfrac{\partial C(x)}{\partial \vec{n}} = 0  
        \quad \forall x\in\partial\Omega \\
        C(x, t=0) = C_{init}(x)
    \end{array}
\right.
\end{equation}
#+end_export