How to create a comprehensive bibliography with splitbib?

I need to split my bibliography into separate sections. The biblatex package pefectly matches my needs but, unfortunately, does not support my customized apacite style. Thus, I have to resort to the splitbib package. What is really annoying, however, is that splitbib requires definition of every single source to be included in the bibliography. Since I am writing a book with several hundreds of references, manually defining the \SBentries{} command is not an option for me. biblatex has this really cool feature to separate bib entires by reference to keywords in the .bib file. Is there a similar option for splitbib to replace the individual entries in \SBentries{} by composite entries defined by keywords?

A mwe (without solution) looks like this:

\documentclass{book}
\usepackage{apacite}
\usepackage{splitbib}
\begin{category}[A]{First Category}
\SBentries{B1,B2}
\end{category}
\begin{category}[B]{Second Category}
\SBentries{A1}
\end{category}
\usepackage{filecontents}
\begin{filecontents}{\bibname.bib}
@BOOK{B1,
author =       {Name1, Surname1},
title =        {Title of the first book in the First category},
publisher =    {Name of the Publisher},
year =         {2017},
keywords =     {firstcategory}
}
@BOOK{B2,
author =       {Name2, Surname2},
title =        {Title of the second book in the First category},
publisher =    {Name of the Publisher},
year =         {2016},
keywords =     {firstcategory}
}
@ARTICLE{A1,
author =       {Name3, Surname3},
title =        {This is the title of first article in the Second category},
journal =      {Name of the Journal},
year =         {2017},
volume =       {01},
number =       {12},
pages =        {1-20},
keywords =     {secondcategory}
}
\end{filecontents}
\begin{document}
I split my bibliography in two section by using the splitbib package. Authors \cite{B1,B2} with the keyword "firstcategory" in the bib. file should appear in the First Category and authors \cite{A1} with the keyword "secondcategory" should appear in the Second Category.
\bibliography{\bibname}
\bibliographystyle{apacite}
\end{document}

• Instead of trying to adapt splitbib why don't you adapt the biblatex style? – Ulrike Fischer May 22 '17 at 11:31
• I really appreciate biblatex over bibtex. But have you ever tried to migrate a highly customized bib style from bibtex to biblatex? This is definitely way beyond my tex skills. – aregat May 22 '17 at 14:18
• You need tex-skills for both solutions so this is not an argument to reject one way. There is a biblatex-apa-style which should be quite near to whatever you want. And by asking good questions (with complete minimal examples!) it should be easy to get the rest. If you want to get the splitbib way you should provide a minimal example that demonstrates your problem too. I at least won't spent my time to build a test environment based on your rather vage description. – Ulrike Fischer May 22 '17 at 14:24
• Why don't you simply believe me when I say that you should provide a minimal example? – Ulrike Fischer May 22 '17 at 15:31
• The main feature of an MWE is that you can run tests with it -- sometimes to test a problem and sometimes to test a solution. Beside this: if your special bst stores the keywords in a usable form in the bbl (apacite in your example doesn't) there is a small possibility to retrieve the keys and their category through the .aux-file. But imho it would be much less trouble to use biblatex. – Ulrike Fischer May 22 '17 at 17:20