Ion exchange has been used for the separation and preconcentration of trace inorganic constituents along with solvent extraction for a long time. Recently, ion exchange has received much attention as an environment-friendly separation technique because it can be implemented without hazardous organic solvents. The author, as an analytical chemist, has applied ion exchange to the separation and preconcentration of trace inorganic constituents in order to improve accuracy, sensitivity, and reproducibility of analytical procedures. The basic policy employed here to design ion exchange systems is to choose eluent solutions, so as to make the minor or trace analytes be adsorbed on an ion-exchange resin and matrix components be removed as non-adsorbing species. The present paper describes the methods of steel and environment analyses using the ion-exchange separations. The analytical methods are outlined here for the determination of molybdenum, aluminum, manganese, nickel, and cobalt in steel, simultaneous determination of iodide and iodate in seawater, and determination of cadmium in soil.

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Characteristics of mono-valent cation permselective membrane “Neosepta CIMS” were measureds. The following results were obtained.
1. Relative transport numbers were slightly dependent on salt concentration compared to normal cation exchange membrane “Neosepta CM-1”.
2. Purity of brine was increased with increasing current density and with decreasing temperature.
3. Purity of brine decreased 1% per year.
4. CIMS can separate between monovalent cations, for example hydrogen and ammonium ions.

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Ultra pure water that is indispensable for producing semiconductor is required quality of ultra high purity in recent years. At the same time, a large quantity of ultra pure water is consumed. Then, various technologies are applied and used for producing ultra pure water combined with environmental problems and cost. The most important elemental technologies of ultra pure water system are ion exchange technology and membrane technology. Ion exchange technology not only removes ions in water but also is effective for removing organic matter and sterilizing bacteria as secondary functions. Additionally, it is used for removing dissolved oxygen, etc. with particular resin. We received Technology Award for 2004 in Ion Exchange Society for our equipment of scrubber waste water reclamation of semiconductor factory using ion exchange system. Then, we introduce briefly the application of ion exchange technology used for ultra pure water system for semiconductor manufacturing fabrication.

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Phenol-Formaldehyde Resin (PFR) is the basic unit for blending of Sulphonated Achyranthes aspere Linn carbon (SAAC) . A few novel composite ion-exchangers were prepared by varying the amount of SAAC in the blends of PFR-SAAC from 0 to 50% (w/w) . Optimum principal reaction conditions for the preparation were obtained. The prepared materials (PFR, composites and SAAC) were characterised by its FT-IR spectral and thermal (TGA) studies. The important Physico-chemical properties of PFR, composites and SAAC are also determined. The synthesised compo-sites are stable in water, organic solvents, thermal treatment and mineral acid (1 M) like HCl but soluble to some extent in 20% (w/v) NaOH solution. It was found that the ion-exchange capacity (IEC) or column/cation exchange capacity (CEC) of the composite resins decreased with increasing the percentage of blending PFR matrix with SAAC. Synthesised composites are used in the study of the possible exchange of Zn²⁺ ions. Equilibrium constants (in terms of ‘ln K’) are calculated for H⁺-Zn²⁺ exchanges on the composite having various amount of SAAC. Thermodynamic parameters are evaluated and discussed. The composites up to 20% (w/w) blending of Phenol-formaldehyde resin (PFR) with SAAC retains almost all the essential properties of the original PFR, including CEC since the Achyranthes aspere Linn (AA) is the low cost, and freely available plant material. Therefore, the blended composites of PFR with SAAC could be used as low cost ion-exchangers, when SAAC partly replaces the original PFR up to 20% (w/w) blending without affecting its spectral, thermal, physico- chemical properties and CEC values of PFR. Hence, blending of PFR with 20% (w/w) of SAAC will definitely lower the cost of ion exchange resin.

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Antimony (III) forms a stable complex with polyols under the high pH condition. The ion binds with hydroxyl groups bonded with two adjacent carbon atoms in polyol molecules. Polysaccharides possess a lot of hydroxyl groups, and 1, 4-glucans such as a cellulose have two hydroxyl groups bonded with adjacent carbon atoms. The glucans in the waste biomass are expected to be reused as an adsorbent for antimony (III) . We examined the potential of 1, 4-glucans for the adsorbent on experimental and computational basis.

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