Salt may be added to the water used during the baptism, but it is not required. There is no mention of salt in the ordinary form of the Rite of Baptism.
Apparently, no. I’ve looked through the text and can’t find any place where it would be permitted. Even the blessing of the water doesn’t contain the option for blessed salt (although it does at the Sunday rite of sprinkling).
DISCLAIMER: Catholic Answers has turned over the archive to Catholic-Questions.org and no longer owns, manages, or moderates the forums. For additional apologetics resources please visit www.catholic.com.