Dear JNgent,
Among many alternative ways to find heat of dilution data, you may try and locate a book titled " Sulphur, Sulphur Di Oxide and Sulphuric Acid " written by UHF Sander, H Fischer, U Rothe and R Kola. This was published by British Sulphur Corporation in 1984 and had ISBN...
To control heat liberation you always add small quantities of s acid to large quantity of water. Thus if you wanted to prepare 1000 kg of 50% s acid, you start with 500 kg of water at room temperature and add concentrated acid slowly with good mixing keeping an eye (!) on the temperature rise...
