A hydrothermal hot-pressing method: Apparatus and application

Fabrication of Low Temperature Foaming Glass Materials Using Hydrothermal Treatment

“…The glass was subjected to a hydrothermal hot-pressing (HHP) technique developed by Yamasaki et al 8) Figure 1 shows a schematic diagram of the autoclave in the HHP apparatus. The autoclave is composed of a stainless steel cylinder with an inner diameter of 30 mm and stainless steel pistons, teflon packings and an external band heater, and can be heated to 623 K. Teflon packings give the airtightness inside the autoclave by compressive modification when the vapor pressure is increased at high temperature.…”

Synthesis and characterization of bulky mesoporous silica Pd-MCM-41

“…Autoclave for HHP in this study showed previous report. 14) Mixture of powder and water was heated at 423 K with uniaxial pressing under 40 MPa and kept constant for 2 h. The bulk prepared by HHP of as-synthesized powder was removed the template of surfactant by calcination at 773 K for 2 h in H 2 . Obtained sample is cylindrically shaped and it has a diameter of 20 mm and 1 mm in thickness.…”

“…It is possible to densify oxide ceramics and glasses because of dissolution and deposition mechanism by means of increasing rate of dissolution and solubility of particles into water under hydrothermal condition. 14) It is thought that the successful synthesis of metal-supported mesoporous silica bulks would lead to the expansion of new application of mesoporous silica. Thus, in this paper, we report the preparation of Pd-supported MCM-41 powder and subsequently attempt consolidation of Pd-MCM-41 powder by using HHP process.…”

Hydrothermal Hot-pressing Solidification of Coal Fly Ash and Its Ability of Fixing Heavy Metal

“…The reaction rate at hydrothermal conditions would be significantly increased, and the diagenetic process of cumulates can accordingly be accomplished in a short time. Yamasaki et al [2,3] found that the high-level radioactive waste could be successfully fixed by borosilicate glass under hydrothermal conditions. Furthermore, HHP solidified specimens of shell powder with a certain amount of organics usually present beautiful appearance like natural marble and can be used as building decoration materials [4,5].…”