Hydrothermal Autoclave reactors have significant role in conducting hydrothermal reaction at high operating pressure and high operating temperature. These hydrothermal apparatus are required to conduct catalyst synthesis, hydrothermal precipitation and various other industrial reactions. Based on application type, these autoclaves are available with PTFE lined and PPL lined versions. Based on lining material type, different operating temperature ranges are maintained in the offered autoclave. Application of Hydrothermal Autoclave reactors can be noticed in material engineering, environmental science, petrochemical, nanotechnology and also in other industries.