Merrow Scientific is supplying instruments incorporating highly-accurate magnetic suspension balances from Rubotherm.
They can measure the mass of a sample remotely with high precision, making them suitable for gravimetric analysis in sorption measurements, such as in research into the storage of hydrogen in materials.
Another application is thermogravimetrics, for example, in corrosion testing of materials at high temperatures and pressures.
Other possible uses are the investigation of gasification processes of biomass or coal, and highly accurate density measurements of gases and liquids.
A key advantage of the Rubotherm instruments is that they use a magnetic coupling and control system, which allows samples to be subjected to high pressures or temperatures and corrosive fluids without affecting the measurement.
Conventional instruments have a physical link between the sample and the high-precision balance, which limits their range of application to pressures of typically 20 bar, whereas the Rubotherm instruments can operate as high as 2,000 bar or 2,000C.
Masses or mass changes can be measured down to a resolution of 1 microgram, with +/-2 microgram reproducibility.
Using these measurements it is possible to determine transport and state quantities easily and accurately (sorption, diffusion, surface tension, density), chemical reactions can be investigated (corrosion, decomposition, combustion) or production processes can be simulated (polymerisation, coating, drying).
In addition to fundamental research work and material testing, magnetic suspension measuring methods can be applied to many processes to design or optimise a number of industrial operations, such as exhaust gas cleaning, purification and storage of natural gas and hydrogen, gasification of coal, production of plastics, soil detoxification, supercritical fluid extraction, waste incineration, material synthesis and foodstuff manufacturing.
