Radiation and thermal stability:

Generally, it is taken as more or less granted that the synthetic inorganic ion exchangers are more resistant to radiation damage than their organic counterparts. However, the studies have shown that it is not justified to make a generalization about them. Each ion exchanger needs to be tested for its radiation stability. A large number of them have been used for processing fission products. The ferrocyanides and salts of heteropoly acids are used for the recovery of Cs¹³⁷. The radiation stability combined with separation capability yields a system which is known as 'isotope generator'. A radionuclide generator is a system/ device which makes the repeated recovery of a short- lived isotope in a pure form from a relatively long- lived parent isotope. A typical example is a Ba¹³¹- Cs¹³¹ generator on hydrous zirconium oxide. Short lived isotopes find use in nuclear medicine for diagnosis and therapy.

By now a fairly good amount of data is available that the thermal stability of inorganic ion exchangers particularly of those amorphous in nature has been over emphasized. A number of amorphous materials start losing their ion exchange capacity on heating. However, some of them are quite resistant to heat. Hydrous Ta₂O₅ is quite heat resistant upto 300ºC and is used for decontaminating nuclear reactor cooling waters. A promising use of these exchangers could be in fuel cells at high temperatures or for concentrating the nuclear waste. Thermally stable ion exchanger in the transition metal forms are used as high temperature catalysts. Layered zirconium phosphate as such or in other metal form has been used for catalyzing different organic reactions.