IKA T 25 digital LR disperser, for laboratory reactors, 2000 ml, 0020008820

Fluid dynamics precision in closed reactor systems

In chemical process engineering, the synthesis of nanoparticles and the production of complex pharmaceutical emulsions, the scale-up from the laboratory to the pilot phase requires absolute control over phase distribution. Conventional, open dispersion processes in beakers inevitably lead to the ingress of atmospheric oxygen (oxidation) due to vortex formation and to the uncontrolled loss of volatile organic compounds (VOCs). The IKA T 25 digital LR disperser (the abbreviation “LR” stands for laboratory reactor) is specifically designed for high-precision high-shear dispersion in hermetically sealed, temperature-controlled and evacuated reactor systems. Powered by a robust 800-watt high-performance motor, this drive unit handles process-relevant volumes ranging from 1 to 2,000 millilitres (based on the physical viscosity of water). The unit thus bridges the critical process engineering gap between initial formulation development on a millilitre scale and simulated industrial production.

Thermodynamics and cavitation in the rotor-stator principle

The breakdown of stubborn agglomerates and the disruption of viscous liquid droplets (emulsification) requires the massive, localised application of kinetic energy. The T 25 digital LR operates with a continuously and electronically adjustable speed range from 600 up to a staggering 25,000 revolutions per minute. In combination with the specific IKA dispersing tools, immense circumferential speeds of over 22 metres per second are generated at the outer edge of the rotor. The radial acceleration of the media into the extremely narrow shear gap between the rotating element and the stationary stator generates immense hydrodynamic shear forces, high-frequency pressure fluctuations and physical cavitation effects. Particles and droplets are broken down into microscopic primary sizes in the low micrometre range within milliseconds. The thermal energy inevitably generated by molecular friction can be dissipated in a controlled manner in a professional reactor system via external cooling jackets, in order to protect thermolabile analytes from denaturation.

Vacuum compatibility and specific reactor geometry

The key design difference between the T 25 digital LR and conventional laboratory homogenisers is its physical and geometric system integration. The unit is mechanically engineered to be precisely coupled with IKA’s specialised KD-LR (laboratory reactor) dispersion tools. These specialised tool shafts feature high-quality, high-vacuum-compatible mechanical seals made of FFPM and PTFE. In this configuration, the drive enables high-speed dispersion under a system vacuum of up to 50 mbar. Evacuating the reactor whilst active dispersion is taking place prevents the formation of disruptive aerosols and foam in media containing surfactants, completely rules out the oxidative degradation of active pharmaceutical ingredients (APIs) and guarantees the production of absolutely bubble-free, highly viscous gels or creams. Furthermore, the LR tools are designed with an extended length to penetrate deep into the reaction vessels (such as the LR 1000) and fully capture even minimal dead volumes at the bottom of the reactor.

Scalability and rheological behaviour of multiphase systems

A fundamental problem in the dispersion of non-Newtonian fluids is the change in rheological properties under sustained shear stress (structural viscosity). Thanks to its precise energy input, the IKA T 25 digital LR enables the exact investigation of these phenomena directly within the reactor. During the production of solid suspensions, the stator breaks down the electrostatic van der Waals forces responsible for agglomeration. In liquid-liquid systems, the turbulent flow prevents the coalescence of droplets until added emulsifiers physically stabilise the interfacial tension.

Digital process control and electronic safety mechanisms

To ensure complete reproducibility in a regulated environment (GLP/GMP), the T 25 digital LR is equipped with an LED display for continuous monitoring of the actual speed. An integrated microprocessor continuously adjusts the power output. If the viscosity of the medium increases due to polymerisation setting in during the reaction, the electronics maintain the speed absolutely constant despite the growing hydrodynamic resistance. To protect the hardware, the drive features multi-stage overload protection. Should the rotor become suddenly blocked in the shear gap, a physical current limiter intervenes immediately, switching off the motor and issuing an error code. This prevents thermal damage to the motor windings and guarantees the longevity of the laboratory infrastructure.

Technical details

• Product type: High-shear disperser for laboratory reactors
• Volume range (H₂O): 1 – 2,000 ml
• Motor power (input/output): 800 W / 500 W
• Speed range: 600 – 25,000 rpm (electronically continuously variable)
• Speed display: Digital (LED)
• Max. permissible viscosity of the medium: 5,000 mPa·s
• Noise level (without dispersing tool): 75 dB(A)
• Operating principle: Rotor-stator technology (high shear forces / cavitation)
• Vacuum compatibility: The system is designed for vacuum operation when used in combination with KD-LR tools
• Process reliability: Electronic speed control maintains a constant speed despite changes in viscosity
• Motor protection: Electronic overload protection and current limiting with error code output
• Permissible duty cycle: 100% (continuous operation)
• Dimensions (W x H x D): 87 x 271 x 106 mm
• Arm length / arm diameter: 160 mm / 13 mm
• Weight: 2.5 kg
• Protection class (to DIN EN 60529): IP 20
• Permissible ambient temperature: 5 – 40 °C

Contents

• 1 x IKA T 25 digital LR drive unit (800 W, for laboratory reactors)
• 1 x mains lead for IT equipment
• 1 x Comprehensive operating instructions

(Important note: The essential KD-LR series dispersing tool, stands and the laboratory reactor itself are not included in the scope of delivery!)

Individual requirements & accessories

The T 25 digital LR is a drive motor only. To operate the system in your laboratory reactor (such as the IKA LR 1000), you must have a suitable dispersing tool designed for a physical vacuum seal (for example, the IKA S 25 KD - LR - 25 G). For a safe and vibration-free setup, you will also need a stand solution, unless the unit is mounted directly onto the reactor stand. Please contact our procurement service at any time for a fluid-dynamically precise design of your rotor-stator geometry and its integration into your reactor system.