Re: Antique Paper--salvagable?
Hi Nancy, Debby had some great idas ideas.
I also have a sketchbook which is brittle and yellowed. The paper is thicker than what you have, it was originally intended as a scrapbook. My mom bound it about 40 years ago and it was untouched when she gave it to me, before "acid free" or "archival" was widely available.
I only use it for acrylic sketches and I always start with a layer of gesso. There are also some things to help with the brittleness of the paper made by Golden, the GAC series (GAC 200, GAC 400, I forget which one) but the paper will still be acidic and you will then have buckling. If the pages are bound, there's no practical way to coat the whole page. Then, after putting an acrylic coating, you might not be able to get graphite to stick.
I have these GAC things but I haven't used it (whoops.) I had intentions but I've all but forgotten what those were. One of them was to coat a cork board as a barrier I have pinned some of my work to.