It’s a perennial question: How do I properly dispose of blessed items?
“There is relatively little written about exactly what to do with liturgical books which have been replaced by updated or revised editions, but some related writings, as well as some common sense, can provide some context. The Book of Blessings, no. 1343, indicates that the Sacramentary, the Lectionary, and other liturgical books are counted among those articles used in the Sacred Liturgy which ought to be blessed using the rite provided for that purpose, the Order for the Blessing of Articles for Liturgical Use (nos. 1341-1359). The Latin De Benedictionibus, editio typica, however, does not explicitly mention the Missale among the articles that are properly blessed.
Read more or download the article at disposing of old missals and sacramentaries.