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An ion-exchange is an established unit operation and is an important supplement to procedures such as filtration, distillation and adsorption. In the laboratories, ion-exchangers are used as an aid in analytical and preparative chemistry. However, the most important application is still the purification and demineralization of water, a perennial challenge since the time of Aristotle and Moses and a task which the growth of population and industries has made even more pressing than ever before. The inorganic ion-exchangers exhibit high selectivities for specific ions resulting in the separation factors much larger than those exhibited by organic resins. The inorganic ion-exchangers unlike organic ion-exchangers have rigid structures and do not undergo appreciable dimensional change during the ion-exchange reactions. The rigid structure leads to specific and unusual selectivities. Earlier attention was focused on hydrous oxides since it was known that they sorbed or co-precipitated many ions. It was soon discovered that hydrous oxides combined with anions such as phosphates, vanadates, molybdates and antimonates produced superior ion-exchangers.

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Obtained Ph.D. in 2001 from Thapar University, Patiala. Presently working as Registrar of Sri Guru Granth Sahib World University, Fatehgarh Sahib, Punjab, India. Published many research papers in international journals. Supervised dissertation work of six M.Phil. students.

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