Stirred Laboratory Autoclaves for chemical reactions under pressure


Büchi Reactors systems are developed to fulfil the actual needs of the Chemical and Pharmaceutical Industries.

Buchi stirred Lab Autoclaves, high pressure reactors

Operation pressure

Full vacuum – high pressure 500 bar solutions

Operation temperature

- 50°C to +500°C

Reactor volumes

10 ml to 250 liters

Materials used

Glass ((Pyrex, Schott), stainless steel, Hastelloy®, Titanium, Tantalum, Zirconium


Interchangeable pressure vessels, configurable reactor head, full view glass pressure vessel, or metal reactors with / without sightglass, with magnetic coupling or magnetic stirrer drive, electrically heated vessel or jacketed vessel.

Application /processes

Catalyst testing
Polymer research


stirrer shapes, pH, sampling, CiP, solid containment/feed, etc.



Engineering, manufacturing, installation


Fine chemicals, pharmaceuticals, polymer research, dyes and many others


cGMP Design, CE conformity, PED conformity, ATEX conformity (explosion proof), FDA conformity

Installation sites

R&D Lab, Pilot Plant, kilo lab, production


jacketed pressure vessels for temperature control with TCU circulators

pressure vessels for electrical heating with water cooling

Stirred Laboratory Autoclaves for chemical reactions under pressure

Buchi Reactor systems feature a modular setup. This allows the use of different reactors in the same system. The exchangeable pressure vessels differ in:

  • Volume
  • Material (Glass, stainless steel, Hastelloy®, Titanium, Tantalum)
  • Pressure rating
  • Jacketed reactors for temperature control by circulator or electrically heated reactors

The design of our pressure reactors or Laboratory autoclaves integrates multiple aspects of chemical engineering and reaction technology like:

  • Mass transfer
  • Mass balance
  • Heat transfer
  • Chemical kinetics
  • Thermodynamics

Buchi stirred Laboratory autoclaves or pressure reactors are built for batch – and / semi batch operation mode. Perfectly matched components, top-quality materials, and the competence and expertise of the Büchi team, guarantee economical and high performance solutions tailored to the customer‘s most detailed requirements. Büchi’s worldwide success represents more than state-of-the-art technology; it stands for fair partnership and skilled, professional support.
For customized reactor designs: ask us.

Büchi Pressure Reactors guarantee:

  • Excellent thermal process control
  • Pure products
  • Safe operation
  • Best performance
  • Economical solution
  • Customized reactor systems
  • Return On Investment (ROI)

Büchi stirred laboratory autoclaves or high pressure reactors:

In Research and development labs of chemical and petrochemical companies as well as pharmaceutical companies or life science companies, the reactors are used for multiple processes such as scale up processes, process development and small scale production. Lab reactors are often used as batch reactors. The operation temperature for such reactors can be from – 50°C up to + 250°C.

The basis of our autoclaves or pressure reactors is the design of chemical reactors. Chemical reactors are used for many different processes. To process many different chemicals, the reactors are built in highly corrosion resistant or inert materials. Due to this fact and due to the reactor design, they can be used as multiple processes and substances.

Buchi autoclaves have a modular design. This allows us to configure a customized system by selecting different standard components. More customization to specific customer requirements is possible and often done. Glass pressure reactors can be used to a pressure up to 12 bar and offer the advantage to allow visual observation of the reaction. If higher pressure is needed, the glass reactor can be exchanged for a stainless steel reactor with a sight glass. Other reactor materials such as Hastelloy C22, Titanium, Tantalum, Zirconium are available.

Heating / cooling temperature control: There are 2 ways of temperature control: A circulator controls the heating of the heat transfer fluid, which is circulating through the jacket of the jacketed reactors. The alternative is to use our btc PID temperature control system which controls the electric heating, built directly onto the pressure vessel.

Inside the reactor, accessories are available. Stirrers are to be defined according to the processed media and process. Stirrer shapes can be impeller, anchor, propeller, Helix or others, arranged as single stirrer or as multi stage stirrer. The stirrers are driven by magnetic drives or by magnetic couplings, allowing the process to run under high pressure or high vacuum. Accessories such as burettes, sampling devices, condensers, massflow controller for gas dosing and many others are built into the top of the reactor. Sometimes, dosing of solids or liquids into the pressurized vessel is requested, other requests like pH control, sampling, catalyst addition, nitrogen purging /blanketing, distillation, reflux distillation are also to be considered. In many cases these reactors are installed in flame proof or hazardous area, so they have to be approved as flame resistant or flame proof , also ATEX certified equipment. The design of this type of reactor has to cover all of these issues. Other safety aspects consider accessories like rupture disc for safe operation under pressure.

We use current - up to date technology to first define flow diagrams or PID or P&ID diagram. Based on these, we design the chemical process unit by 3D engineering software

By combining our pressure reactors with our Buchi pressflow gascontroller systems, we can offer a turnkey hydrogenation solution, which stands for safe, precise, reproducible and easy to perform hydrogenations.

In research, automation becomes an important factor. The degree of automation varies a lot depending on the application. It can be a simple measuring of process parameters, a controlled dosing of liquids or gas, or a fully automated Pilot Plant or kilo lab for small scale production.


metal-free / inert pressure reactors:
«miniclave inert»
Lab to pilot scale metal-free / inert reactors

Lab to pilot scale metal-free / inert reactors
Pressure Reactors or Stirred Laboratory autoclaves:
«miniclave drive»

High-pressure reactors or stirred autoclaves:
«limbo ls»


Mid - to large scale pressure reactors: