Hydrothermal synthesis means the techniques crystallizing substances such as metal salt, oxide, hydrate, or metal powders which depend on solubility, temperature, pressure and solute concentration in solution or suspension.  

 Liquid Phase Synthesis is synthesizing method in high temperature and pressure by using a water or aqueous solution. Mineralizer contributes the solubilization, accelerate nucleation of compound in liquid. Mineralizer not only just lowers the temperature but also generates compound selectively, so it is necessary for hydrothermal synthesis. Ilshin Autoclave's Hydrothermal Synthesis system can perform hydrothermal synthesis of various materials.

Most of powders are crystallized in 300, 85 /. Our equipments provide accurate temperature and pressure for process. Ilshin Autoclave Co.,Ltd obtained ASME pressure vessels certification of design & manufacturing, also have Korea Gas Safety Corporation and The Korea Occupational Safety and Health Agency certification so can ensure safety.  



The advantages of hydrothermal synthesis

• Fast reaction and dispersion (It’s suitable for generating solid solution / compounds)
• Control pressure, temperature, solution, and addictives.
• Weaknesses of usual liquid phase synthesis (ex: co-precipitation, hydrolysis method)
 
Weaknesses of usual liquid phase synthesis (ex: co-precipitation, hydrolysis method)
- Non-uniformity when removing residual solvent
 - Inhomogeneous crystallization
 - Cause pollution / agglomeration when performs sintering or pulverization  
 
 
Major materials using hydrothermal synthesis

* Hydrothermal Synthesis (BaTiO3) 
1) Properties : High dielectric constant and thermostability → ferroelectricity, piezoelectricity
2) Applications : Capacitor, thermistor, sensor, communication filter, microwave filter, NVM(non-volatile memory),
DRAM(Dynamic Random Access Memory), heat detector, optical waveguide
 3) Manufacturing process drawing of hydrothermal synthesis

Hydrothermal Synthesis (ZnO)

1) Stirring speed : zinc chloride (Zncl2) / zinc acetate (Zn(Ac)2)

  Starting material  -  Zinc chloride

    ZnCl2 + 2NaOH -> Zn(OH)2 + 2NaCl -> ZnO +H2O + 2NaCl

  Starting material - Zinc acetate

    Zn(AC)2 + 2NaOH -> Zn(OH)2 + 2NaAc ->ZnO + H2O +2NaAc

 - Reaction temperature

 - Process time 6 hours

 - Precipitant : 1M NaOH (dropping 10ml/min)

 - Stirring speed 200rpm

2) Change of Zno according to Staring Material

3) Change of Zno according to Mole Concentration

4)Change of Zno according to time

5)Change of Zno according to temperature

6)Change of Zno according to pH

Benefits of Ilshin Autoclave's Hydrothermal Synthesis Reactor

Safety
• Design and manufacture according to ASME(American Society of Mechanical Engineer), pressure vessel standards.
• Design and manufacture according to KGS and KOSHA.
Accurate equipment 
• Improve process time and equipment efficiency by installation of heater
• Maintain constant temperature by internal/external insulation
• Improve safety through the multi-safety devices 
Customized engineering

 • A variety of types and specification for customer
  • Different types of research are available by various additional components.
Easy assembly/disassembly and clean up
• A variety of measurements facilitate analyzing operating conditions.
• Easy assembly/disassembly and clean up