Gravimetric Sorption Analyzer - IsoSORP®

At the core of the IsoSORP^® Sorption Analysis instruments lies the Magnetic Suspension Balance for accurately weighing the sample material. Rubotherm’s patented Magnetic Suspension Balance enables extremely accurate weight measurements to be taken of samples in closed vessels.

The sample is weighed from the outside and the suspension force is contactlessly transmitted from the pressurized measuring cell to a microbalance at ambient atmosphere. This means that the sorption ability of a sample in a closed reactor can be examined even under challenging conditions like toxic atmospheres and/or high pressure with maximum accuracy.

Unique Features of the Magnetic Suspension Balances Technology - used in all IsoSORP Instruments

Contact free weighing under extreme conditions - The patented magnetic suspension coupling allows weighing in hermetically closed reactors. By separation of measurement area (sample) and weighing area (balance), contamination or damage of the balance caused by experimental conditions or process media can be avoided. The reactor is totally metal sealed and heated so that even extremely aggressive or corrosive vapors or fluids can be used over an extensive temperature and pressure range.

Excellent long term stability - The sample can be automatically disconnected from the balance at any time to recalibrate or re-tare the balance. Subsequently, the sample is reconnected to the balance and the measurement continued. This way, high precision long term measurements can be done without any accuracy loss or baseline drift.

Simultaneous density measurement - With IsoSORP instruments, the sample weight and the density of the process fluid can be established in a single measurement. This is accomplished by weighing a titanium sinker as second inert sample.

Modular construction - The Magnetic Suspension Balance can be easily adapted to new applications. Current instruments can be upgraded with a number of functional modules. Many custom configurations have already been realized.

Technical Versions

The IsoSORP^® instruments can be equipped with various versions of the Magnetic Suspension Balance with the following specifications:

Application Examples for Isosorp Sorption Analyzer

Adsorption isotherms and kinetics - by gas physisorption and chemisorption measurements with zeolites, activated carbon, catalysts, silica, clay, molecular sieves

Gas Storage - gas storage capacity measurements with classical and new materials (metal-organic frameworks, carbon nanotubes, metal hydrides, ionic liquids)

Surface area and porosity - by gas physisorption, density and buoyancy measurements with catalysts, clay, silica, zeolites, activated carbon, molecular sieves

Absorption and solubilities - by gas solubility measurements in polymers, liquids and other materials

Diffusion and permeation - measurements of the diffusion coefficient of ad- / absorption processes of gases and mixtures

Temperature programmed desorption - determining binding energies or heat of adsorption by desorbing loaded sample material at elevated temperature

Separations - a measurement of the selectivity of mixed gas sorption

Thermogravimetry - the introduction of new application areas for TGA by measurements under high pressure or with aggressive vapors and fluids

Vapor permeability and diffusivity - measurements of membranes, packing materials, blisters and foils

Catalyst - coking, sulfidation processes, and lifetime testing

Corrosion studies - of alloys for high-temperature applications in gas turbines or power plants

Filter material testing - by measuring the selectivity and capacity for pollutants

Wetting and drying processes - of construction materials, pharmaceuticals and solid fuels

Incineration or conversion of toxic - chemical and biological materials by high temperature and/or high-pressure vapor