specific analyses applicable to resins

granulometry

A resin granulometry is determined with the wet resin using a sifter that operates under water.

50 or 100 mL of resin are placed on the top screen. The protocol specified under material properties can be applied provided measurements taken for each screen are expressed in volume for the purpose of calculating percentages.

resin capacities

cations – measurement of total capacity

for low acidity cationic resins

A sample of resin that was regenerated via saturation in hydrochloric acid is rinsed and brought into contact with a known quantity of sodium hydroxide. The excess sodium hydroxide is then titrated and the volume of resin precisely measured. The sodium hydroxide is compared to the resin volume to provide the total capacity.

for high acidity cationic resins

A sample of resin that was regenerated via saturation with hydrochloric acid is rinsed.

An NaCℓ solution is then percolated until it shows up as neutral on a pH paper. The displaced acidity is titrated in the effluent and the volume of resin measured precisely. The acidity released compared with the volume of resin provides the total capacity sometimes named the salt-splitting capacity.

anions – measurement of salt-splitting capacity and of total capacity

low alkalinity and high alkalinity anionic resins

A sample of resin that has been regenerated via saturation with sodium hydroxide is rinsed. An NaCℓ solution is then percolated until it shows up as neutral on a pH paper. The displaced alkalinity is titrated in the effluent and compared against the volume of resin to provide the salt-splitting capacity. The same sample of resin is then put in contact with a known amount of HCℓ. The excess acid is titrated. The fraction consumed represents the resin low capacity. The total capacity is obtained by adding together the salt-splitting and the low capacities measured.

resin pollution

organic matter

A volume of resin is brought into contact with a known volume of NaCℓ (100 g · L^-1) and NaOH (20 g · L^-1) mixture for 12 hours. The TOC or permanganate oxidability of the resulting solution is measured providing the quantity of organic matter eluted expressed as a weight of oxygen or weight of organic carbon per litre of resin.

iron

A known volume of resin is brought into contact with a known volume of hydrochloric acid and maintained at a temperature of 80 to 90°C for 30 minutes. The iron measured in the resulting solution is used to calculate the weight of iron eluted per liter of resin.

silica

A known volume of resin is brought into contact with a known volume of soda lye and maintained at a temperature of 80°C. The silica measured in the resulting solution is used to calculate the weight of silica eluted per liter of resin.