Ion exchange process of softening hard water, Chemistry

Q. Describe the ion exchange process of softening hard water. What are its advantages? 

Ans.

Determination of ion exchange or Deionization process: In this process ion exchange resins are used to remove all minerals for water. It is a cross linked organic polymer network having some ionisable group. It can be divided into two types on the basis of the nature of the ionisable group.

 

1.      Cationic exchange materials (RH+): Synthetic resin like sulphonated copolymers of styrene and diving benzene and sulphonated phenol aldehyde polymers act as cations exchangers. They react with water containing salts which contains hardness, the cationic portion of the minerals or salts are replaced by hydrogen ion. It can also be regenerated by the action of hydrochloric acid.

 

2.      Anionic exchange Materials (R'-OH): Synthetic resins which are produced (a) by the interaction of polyamines phenol and formaldehyde. (b) By the nitration and subsequent reduction of copolymers of styrene and diving benzene act as anion exchangers.

Process: The raw water is first passed through cations exchange react with water containing salts which causes hardness, the cationic portion of the minerals or salts are replaced by hydrogen ion. It can be also regenerated by the action of HCl.

H2R + CaSO4 = CaR + H2SO4

H2R + MgSO4 = MgR + H2SO4

 H2R + Ca (HCO3)2 = CaR + 2H2O + 2CO2

                                      H2R= Cations resin exchanger.

After cations exchange column, the hard water is passed through anion exchange column. They exchange the anionic portion of the materials from water by OH- ions of anion exchanger.

R-OH + HCl = RCl + H2o

2R-OH + H2SO4 = R2SO4 + 2H2O

Here R-OH = Anionic resinous exchanger.

Thus, the water coming out from the exchange is free from cations as well as anions, is known as deionised or demineralised water.

Advantages:

1.      Highly acidic or alkaline water can be softened.

2.      Water of very low hardness is obtained. So it is very good for treating water for use in high pressure boilers.

3.      Coloured ions and turbidity is removed.

Posted Date: 7/21/2012 7:11:14 AM | Location : United States







Related Discussions:- Ion exchange process of softening hard water, Assignment Help, Ask Question on Ion exchange process of softening hard water, Get Answer, Expert's Help, Ion exchange process of softening hard water Discussions

Write discussion on Ion exchange process of softening hard water
Your posts are moderated
Related Questions

Molecular formula of gaseous hydrocarbons   (Eudiometry) Eudiometry is a direct method for calculation of molecular formula of gaseous hydrocarbons without ascertaining the pe

Determine the Coordination number (CN) of HCP  In HCP unit cell, the base centered atom touches six corner atoms in the similar plane, three atoms in a plane above and thre

Q. How to Determine Electron Affinity? Ans. Electron affinity is the measure of an atom's tendency to form a negative ion. Electron affinity can be measured by the amou

Limitations of flame photometry: The limitations of the techniques involve the following. The low temperature of the natural gas and air flame limits a method to simply

Q. How reliable are measurements? When scientists glance at measurements they want to know how accurate as well as how precise the measurements are. Accuracy demotes to how c

A 75g piece of Ag is heated to 80 degree celcius and drooped into 50g of water at 23.2 degree celcius.The final tempereture of Ag-H2O mixture is 27.6degree celcius.what is the spec

Q. For a homogeneous reaction in which the reactants and products are solutes in a solution, write a rigorous relation between the standard molar reaction enthalpy and the temperat

Electronic displacement in covalent bonds It is examined that most of the attacking reagents all time possess either a positive or a negetive charge, hence for a solution to op

Face cetered cubic structure In FCC structure, the atoms are situated at each of the eight corners and at the centers of all cube faces of the unit cell. Every face centered at