Two Boston College employees received royalty payments from a book based on interviews conducted at the college about the Troubles in Northern Ireland, even though the college has criticized the author for publishing the book. Ed Moloney, the author of “Voices from the Grave,’’ a book published in 2010 and based on interviews he and others conducted for the Belfast Project at BC, sent emails to the Globe yesterday showing a record of payments totaling about $6,400 made last year to Robert K. O’Neill, librarian at the college’s John J. Burns Library, and Thomas E. Hachey, a professor of history at BC. .