ion exchange

ION EXCHANGEAnup Ghimire

Rock Face Limited

The ProcessO It is a process of exchange of ions

between the insoluble resin and the

solution.

The Process

O R-H + A+ < -- > R-A +H+

O R is the insoluble matrix of the ion

exchange resin.

O R-H is cation exchanger.

O H+ replaces every A+ ions in the

exchange process and electron

neutrality is maintained.

Ion Exchange

O Ion exchange is a natural process

occurring in tissues of plants and

animals, soils and minerals.

O Assists to remove the cations and

anions present in the water solution.

Applications

OThe treatment of radioactive

and non-radioactive chemical

species.

…applications

OSoftening, de alkalization,

demineralization, nitrate

removal, condensate polishing.

and pollution control.

Effect of Ions

O Heating systems, steam generation and

manufacturing process are affected by

the presence of ion concentration in

water particularly cations such as

calcium, magnesium, sodium and

potassium and anions such as sulphate,

chloride, nitrate and silica.

Ion Exchangers

OStrongly acidic

OStrongly basic

OWeakly acidic

OWeakly basic

…Ion exchangers

Naturally occurring and synthetic

O Inorganic ion exchangers have greater

selectivity and better disposal options

than organic resin

O organic ion exchangers are reliable

and efficient in water coolant systems

…ion exchangers

O Mineral compounds such as

bentonite, Kaolinite and Illite and

Zeolites such as analcite,

chabazite, sodalite and

clinoptilolite are naturally occurring

inorganic ion exchangers.

…ion exchangers

O Polysaccharides such as cellulose,

algic acid, straw and peat, proteins

such as casein, keratin and collagen

and carbonaceous materials such as

charcoals, liquites and coals are

naturally occurring organic ion

exchangers.

…ion exchangersO Zeolites, Titanates and silico-

titanates, transition metal

hexacyanoferrates are inorganic

synthetic ion exchangers.