Sputum can be disinfected by all except
Autoclaving
Chlorhexidine
Boiling
Cresol
Autoclaving is the safest and most effective method for sputum disinfection Incineration is an effective alternative. Boiling used after an initial disinfection by 5% phenol (carbolic acid) or its derivatives like Lysol and Cresol.
General Microbiology Pa-2 and Pa-3 (Sterilization and Bacterial Genetics)