| 摘要 |
The invention relates to an installation and process for the synthesis of nanocrystalline materials by the hydrothermal method with multi-assisted multimodal immersible thermal source used for producing nanocrystalline oxide materials. The claimed installation comprises a body () consisting of a steel cylinder () lined with a teflon body () sealed with a gasket () and closed with a lower lid (), a steel cover () having a steel cylinder () attached thereto, said cylinder being covered with a teflon jacket (), said cover () being rigidly closed, at the lower part, and sealed, at the upper end, with a gasket () wherethrough there is introduced a heat source () wound on a ceramic support () which is immersed into a growing solution in the autoclave, through a teflon ring (), some probes () measuring the temperature in the autoclave, an overpressure relief valve () mounted on the cover, opening at 28 atm, two systems provided with the pressure taps () allowing the sampling and the insertion of various reaction precursors, a sonotrode () and a protection steel lid () lined with teflon protective material (). The claimed process consists in decomposing some precursors in the liquid synthesis medium and crystallizing the nanoparticles as follows: in two Berzelius beakers there are admixed separatedly two aqueous solutions consisting of precursor () with precursor () and precursor () with the precursor () up the complete dissolution, the two solutions are admixed and introduced into the autoclave at a filling degree of 80%, the mixture is heated until a process temperature of 200...280°C and a pressure of 23...28 bar are reached and said parameters are maintained constant for a predetermined period of time until the formation of the nucleation centres and the growth of nanocrystals to the desired dimension, afterwards the nanoparticles are filtered and washed with deionized water, dried and packaged. |
