Application

Our TG apparatus enables thermogravimetric measurements to be carried out in highly aggressive atmospheres, at high pressures, in steady atmospheres or flowing media - and with many more advantages besides! No condensation occurs, no flushing gas is needed. Long term measurements over several months are possible with a reproducibility better than 0.03mg. Samples of a few mg up to over 500g can be weighed / measured at temperatures up to 1400K and pressures up to 10MPa. (2300K and 60MPa in special versions). All this is made possible by using magnetic suspension balances for the contactless force transmission from a closed measuring cell through a wall to a microbalance located under normal atmospheric conditions.

Application

-                     Decomposition studies

-                     Gasification of coal and other organic materials

-                     Coating

-                     Corrsion residue incineration

-                     Flue gas desulfurization

-                     Reaction kinetics

Metal version for high- and low-pressure thermogravimetry

Depending on pressure range, temperature range and composition of the measuring gas, the metal version of the suspension balance is equipped with similarly designed measuring cells of ODS-superalloys, quartz glass or ceramics. An oven can be arranged either outside, as shown in the sketch, or even inside the tubular body of the measuring cell.

Thermogravimetry without flushing gas

In all cases the use of flushing gas is unnecessary. To avoid disturbances of the measurement by condensation or precipitation of reaction products on suspension parts, a small part of the measuring gas is fed in at the top of the coupling housing and flows down through a wire tube towards the sample while the main gas flow reaches the sample from underneath. Due to the high maximum operating temperature of the suspension coupling, a minimum overall temperature level in the measuring housing of 700K can be achieved. Therefore, every part of the housing, including the suspension coupling, is bakeable in vacuum up to this temperature. 

Thermogravimetry Quartz glass suspension coupling for highly aggresive media

If the measuring gas is known to corrode stainless steel surfaces even at low temperatures, the coupling housing including suspension magnet can be replaced by the glass version previously mentioned. For reduced sample temperatures up to 1200K the measuring cell can also be completely made out of quartz glass.