Various inorganic ions and metal complex ionswere chromatographed on a tightly cross-linked polyacrylamide gel (Bio-Gel P-2) column using the aqueous solutions of sodium acetate, sodium chloride, sodium nitrate, sodium perchlorate, lithium chloride, and potassium chloride as eluents. Based on the ion partition mechanism presented by the authors, the theoretical equations concerning the background eluent counterion effect (eq. 1) and coion effect (eq. 2) on the distribution coefficient of sample ion, S^m+, are derived as follows lnK_av, ^YX_S=m/2nlnK_av, ^WZ_X+C₁……(1)
lnK_av, ^YX_S=-m/2plnK_av, ^WZ_Y+C₂……(2)
where K_av, ^AB_i is the distribution coefficient of ion, i, when eluted with the solution of elecrtolyte, AB, and C₁ and C₂ are the constants for the ions of the same valency n- (X^n-) and those of the valency p⁺(Y^p+), respectively, provided the size exclusion effect does not operate predominantly. The experimental results agreed well with the prediction from eq. 1 and 2, strongly supporting the validity of the presented theoretical model for the partition mechanism of ionic solutes between the external liquid phase and the gel phase. It was also demonstrated that the distribution coefficients of ionic solutes can be estimated semiempirically on the basis of the theoretical approach presented; the calculated values were in good agreement with the experimental ones.

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Separation behavior of inorganic anions and organic acids is discussed by non-suppressed ion chromatography with a short column (5 cm×0.46 cm I. D.) packed with a silica-based ion exchanger (TSKgel IC-Anion-SW), which is prepared by chemically bonding diethylaminomethyl group on the surface of hydrophilic packings with the trade name TSKgel G2000SW. This has a particle diameter of approximately (58)μm and an exchanger capacity of approximately 0.4 meq/g. Monovalent inorganic anions were completely separated with a 1 mM tartaric acid (pH 3.2) or 10mM potassium benzoate (pH 6.6) solution as eluent, and divalent inorganic anions with a 4mM potassium phthalate (pH6.5) or 1mM ammonium citrate (pH 6.5) solution as eluent. Aromatic-organic acids were easily eluted with a 0.5 mM ammonium citrate (pH 6.5) solution as eluent. The results obtained with conductometric determination were confirmed by comparison with direct or indirect UV absorbance and electrochemical detection. This approach will be applied to the rapid separation of hydrophobic ionic species and the mutual separation of hydrophilic ionic species.

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Trace amount of bromide ion in sea water as concentrated salt solution was determined with solvent extraction and ion chromatography. Analytical procedure is as follows: Ten ml of a sample is put in a test tube with a stopper and 5 ml of CCl₄, 2 ml of KNO₃-HNO₃ buffer solution (pH 1.0), and 0.6 ml of 0.15 % NaClO are added. The mixture is shaken vigorously for 1 min, then poured into a solvent extractor. The bromine is extracted into CCl₄, separated, and reduced to bromide ion by H₂O₂ solution which is acidified with acetic acid. The bromide ion is determined with ion chromatography. The chromatogram showed only three peaks of trace Cl^-, OAc, and Br^-. Seven sea water samples were collected at the coast of Niigata Pref., Sakata City in Yamagata Pref., and Oshima Pen. in Hokkaido Pref. The analytical results were (71.358.4) ppm. The concentrations were higher at near Hokkaido and lower at beaches in Niigata Pref..

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It is known that 3-acetoxymethyl cepharosporanic acid injection partially decompose to liberate acetic acid in an aqueous solution and the resulting desacetyl derivative has only a low potency. For the purpose of the simple and rapid determination of the acetic acid liberated in the aqueous injections, ion chromatographic technique was examined. By the use of the column packed with Amberlite XAD-4 resin {(100200) mesh} as separator, acetic acid in the injections can be analyzed without any tedious pretreatment except for simple dilution with deionized water. This technique was applied to the analysis of acetic acid in the sodium cefacetrile (CEC) aqueous injections. The results of this study also indicate that although the CEC aqueous injections are relatively stable under low temperature (4°C), acetic acid is liberated in proportion to the preserving time when stored at room temperature (25°C).

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The liquid chromatographic separation of maleonitriledithiol (MNT, H₂L) complexes of palladium (II) and platinum (II) ( [PdL₂] ^2- [PtL₂] ^2-) was established. by reversed phase ion-pair chromatography. Procedure: Transfer less than 35 cm³ of the sample solution containing (0.250)μg palladium(II) and (0.5100) μg platinum (II) to a 50 cm³ beaker. Add 0.5 cm³ of 0.1 mol dm^-3 EDTA and 0.5 cm³ of 1 mol dm^-3 acetic acid, and adjust the pH to about 5 with 0.1 mol dm^-3 sodium hydroxide solution. Then, add 3 cm³ of 7×10^-3 mol dm^-3 MNT solution and transfer this mixture to a 50 cm³ volumetric flask and dilute to a mark with distilled water. Transfer this mixture to a 50 cm³ cylindrical glass vial fitted with plastic cap, and heat for 40 min at 80°C. After cooling to room temperature, inject 100 mm³ of this mixture with loop injector into ODS-silica column (Radial Pak C₁₈). A 42 wt % tetrahydrofuran-water containing 0.2 wt % tetrabutylammonium bromide, 0.02 wt % EDTA, and 0.1 wt % acetate buffer (equimolar mixture of acetic acid and sodium acetate) was used as a mobile phase at a flow rate of 1 cm³ min^-1. The MNT complexes were detected at 320 nm and calibration curves were linear over the concentration ranges of 2×10^-8 to 10^-5 mol dm^-3 for palladium (II), 5×10^-8 to 10^-5 mol dm^-3 for platinum (II). The detection limits (S/N= 2) were 10^-8 mol dm^-3 for palladium (II), 2×10^-8 mol dm^-3 for platinum (II). The coefficients of variation for 7.82×10^-7 mol dm^-3 of palladium (II) and 7.91×10-7 mol dm^-3 of platinum (II) were 1.46 % and 1.57 %, respectively (5 determinations). This method is the most sensitive spectrophotometric method for determination of palladium (II) and platinum (II).

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A method for the determination of lower carboxylic acids in ambient air was developed, based on the sampling of lower carboxylic acids, concentration of the sample solution and determination of the concentrated solution by ion chromatography. Carboxylic acids in the ambient air were effectively collected into pure water. The recoveries of carboxylic acids in the concentration process of the alkaline solution from 600 ml to 2 ml were higher than 92%. The order of elution was propionic, acetic, lactic, and formic acids. Detection limits of each carboxylic acids with a conductivity detector with a penta-pole ring electrode were 0.01 μg/ml with an exception of 0.005μg/ml for formic acid. In the field measurement with this technique at Hiratsuka district in Kanagawa Prefecture, formic and acetic acids were determined and a substance whose elution time was identical with that of lactic acid was detected in the ambient air.

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A potentiometric detector based on an ion-selective electrode (ISE) was constructed and used to determine anions by ion chromatography. The ISEs employed were two types: one is silver-silver halide electrodes (Ag-AgCl, Ag-AgBr, and Ag-AgI) and the other is an epoxy resin matrix electrode using trioctylmethyl-ammonium ion as sensing material. The detectors based on the former electrodes respond specifically to halide and pseudo-halide ions. In case of using CH₃COOH-CH₃COONa solution (2×10^-3 M, pH 6.4) as eluent, 6 species of anions (Cl^-, Br^-, I^-, SCN^-, CN^-, and S^2-) could be detected down to 2×10^-6 M (100 μl-injection) with a detector based on an Ag-AgCl electrode. On the other hand, a detector based on the latter electrode could determine more various anions. In particular, the detector was highly sensitive to NO₂^-, NO₃^-, ClO₄^-, I^-, and SCN^-. The detection limit for these ions was 5×10^-5 M at 100μl-injection. The double column chromatography using separation and suppression columns with 5×10^-3 M NaOH solution as eluent was the most efficient system for the detection of anions with a detector based on an epoxy resin matrix electrode. Anions of NO₂^-, Br^-, and NO₃^- could be detected down to 1×10^-6 M (100 μl-injection). The sensitivities of most detectors constructed were kept constant for at least 2 months. The detector can be easily constructed with exchangeable detector assemblies including ISE, which is also prepared with ease. This provides an additional advantage to the detector.

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A simultaneous determination of small amounts of copper (II) and zinc (II) was developed with α, β, γ, δ-tetrakis(4-hydroxyphenyl) porphine (THPP) by high performance liquid chromatography (HPLC). Recommended procedure: Take a sample solution containing up to 2.0 μg of Cu (II) and Zn (II), respectively, into a 100 cm³ round-bottom flask, add 5 cm³ of ethanol, 1 cm³ of pH buffer solution (pH 8.0 8.5, ethanol 40 v/v %), and 5 cm³ of 5×10^-5 mol dm^-3 THPP ethanol solution. Heat and reflux the mixture for 10 min and allow to cool to room temperature and then dilute to 25 cm³ with water. Inject 0.1 cm³ of the mixture into the HPLC system {mobile phase: 75 v/v % ethanol-water solution, column: Radial Pak C₁₈ (Octadecylsilanized silica, 8 mm i. d.×100 mm), and flow rate 0.6 cm³/min} and record the chromatogram at the wavelength of 420 nm with the absorbance unit full-scale, 0.16. The molar absorption coefficients at 420 nm were 3.2×10⁵cm^-1 mol^-1 dm³ in both copper and zinc complexes. The peak height calibration curves of these metal ions were linear in the range of 02×10^-6 mol dm^-3, and the coefficients of variation (5 determinations) at a center of the above range were 2.1% for Cu (II) and 3.4% for Zn (II). The method was successfully applied for the determination of copper and zinc in tap water.

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Nonsuppressed ion chromatography using potassium hydroxide solution as an eluent is a very sensitive method to determination of inorganic anions in Lake Biwa and investigated the correlation between this method and the other analytical methods (ion selective electrode or spectrophotometry). The anion exchange resin column was TSKgel IC-Anion-PW {4 mm i. d.×50 mm, particle size (10±2)μm, capasity (0.03 ± 0.005) meq/g}. The volume of the sample loop was 100 μl. The column and a conductivity detector were maintained at 30°C. The flow rate of the eluent was kept at 1 ml/min under a pressure of (1520) kg/cm². The eluent concentration of 2 mM was chosen because of the short analysis time and good separation. Sulfate ion was not determined since it overlapped with carbonate ion in the eluent and in the sample solution. The concentration of F ^- determined by this method was much larger than that determined with ion selective electrode or by spectro-photometry of lanthanum-alizarin complexone method. This phenomenon was caused by the simultaneous elution of F ^- and some low molecular weight organic acids such as acetic acid. For the determination of Cl^- and NO^-₃, good correlations were obtained between the data obtained by this method and those by conventional spectrophotometry, and the correlation coefficients were 0.998 and 0.977, respectively. The coefficients of variation with ion chromatography were 0.17 % for 8 ppm of Cl^- and 3.51 % for 670 ppb NO₃^-.

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The reversed-phase ion-pair chromatography of 2-(2-thiazolylazo)-4-methyl-5-(sulfomethylamino) benzoic acid (TAMSMB) chelates with copper (II), nickel (II), cobalt (III), and TAMSMB was studied using ODS columns, and the method for the simultaneous determination of copper, nickel, and cobalt was developed. The effects of the composition of the eluent on the retention were examined. The watermethanol (70: 30 v/v) solution containing 0.075 mol dm^-3 sodium chloride, 10^-4 mol dm^-3 TAMSMB and 0.01 mol dm ^-3 acetate buffer (pH 4.04.3) was the best as eluent. The procedure for the determination: A sample solution was taken into a 25-cm³ volumetric flask, and 2 cm³ of TAMSMB solution (5×10^-3 mol dm^-3), 5 cm3 of acetate buffer (0.1 mol dm^-3, pH 5), and 2 cm³ of potassium periodate solution (0.4 %) were added, and the solution was diluted to the mark. This solution (100 mm³) was injected into a glass column (4 mm I. D.× 200 mm, ODS-silica), and the eluent was delivered at the flow rate (0.70. 8) cm³ min ^-1 TAMSMB chelates eluted in the order of cobalt, copper, and nickel were detected at 580 nm. The calibration curves were linear for (5120)ng Co, (280)ng Cu, (5140)ng Ni, and the limits of detection (S/N= 3) were Co 5 ng, Cu 2 ng, Ni 5 ng. This method was applied to the determination of cobalt, copper, and nickel in a glass sample. The chromatography using a micro column (0.5 mm I. D.×95 mm) was also studied.

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A simple and rapid method was established for the separation and determination of octahedral geometric isomers of cobalt (III), chromium(III), and rhodium (III) chelates of benzoylacetone (BA) and trifluoroacetylacetone (TFA) by high-performance liquid chromatography (HPLC). The HPLC separation of cis and trans isomers of the three BA chelates was performed on an alumina column (Woelm Alumina basic, 25μ, 4mm×50cm), using hexane-2-propanol (100:0.15) as the eluent. The separation of cis and trans isomers of the three TFA chelates was achieved on a silica gel column (Waters μ Porasil, 10μ, 3.9mm×30cm), using benzene-hexane (60:40) as the eluent. By maintaining the temperature of the column at (22.0±0.1)°C in a thermostat during HPLC operations, the reproducibilities of the retention times and the peak heights were improved (averaged1% and1.4 %, respectively), and the linear calibration curves were obtained in the concentration range of (10^-610^-3)mol/l for the twelve isomers studied. The average of the correlation coefficients of the calibration curves obtained for twelve isomers was 0.9995. The detection limits of the isomers were in the concentration range of (16)×10^-6 mol/l and were (1.2×10^-11, 2.8×10^-12)mol for 2 μl of sample. The recovery and the coefficient of variation of the determination of these isomers were (96.1104) % (average 98.8%) and (0.62.8)% (average 1.3%), respectively.

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Ion exchange chromatography of alkali metal, ammonium, and alkaline earth metal ions were studied by using a conductivity detector. Low-capacity cation exchangers were prepared from several kinds of styrene-divinylbenzene (S-DVB) copolymers by sulfonation with concentrated sulfuric acid under the various conditions of temperature and heating time. Sulfonated resins were packed into stainless steel columns of 4.6 mm diameter and 250 mm lengh. Spherical, gel-type S-DVB copolymer (average diameter 10μm) was sulfonated to appropriate degree for above cations at (80100)°C for (210)min, and showed excellent separating performance. Suitable exchange capacity is (2040)μeq/column for alkali metal and ammonium ions when 5 mM nitric acid is used as an eluent. When (2.55) mM ethylenediamine dihydrochloride is used as the eluent for alkaline earth metal ions, exchange capacity of (60120)μeq/column is adequate. With resin containing 2% of DVB, good shape chromatograms could be obtained. Linear relationship between the concentration of sample ions and the conductivity peak height were obtained when total concentration of sample ions is lower than that of the eluent. Influences of copresent ions are easily excluded. Selectivity constants for alkali metal ions are a little different from the values for conventional cation exchangers.

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The liquid chromatography system consists of a series of two columns of H⁺ -form cation-exchange resin (5 mm i. d.×50 mm length) and ODS resin (3 mm i. d.×50 mm length), and SO^2-₄ -form anionexchange resin for separation column (3 mm i. d.×150 mm length) and UV spectrophotometer for detection. Nitrate was eluted from anionexchange column by 0.05 M sodium sulfate solution as an eluent, and detected by monitoring the absorbance at 210 nm. It was found that the proposed method was highly sensitive, rapid and reliable by using two pre-columns for the removal of interfering substances. The calibration curves in the concentration ranges of (01000, 0100, 010) ppb nitrate-nitrogen were linear. The detection limit of nitrate-nitrogen was 1 ppb and the time for single determination was within 10 min. The analytical results for nitrate in samples of lake Biwa by the proposed method were agreed well with those by the copper-cadmium reduction method. The correlation coefficient between these data was 0.997.

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To obtain horizontal distribution of photochemically generated ions in aerosol above Kanto area, and to investigate the effect of the wind profile conditions on photochemical smog generation, we conducted photochemical smog survey above Kanto area by using a small aircraft. The wind profiles of Kanto area were obtained by pilot ballon measurement at 23 positions. Ambient aerosol above Kanto area were collected by the sequential sampler equipped with polytetrafluoroethylene filter, then the water soluble components were extracted and analysed by ion chromatography. There are mainly chloride, nitrate, sulfate, and ammonium ion above Kanto area. The horizontal distribution of water soluble ions were obtained and the correlation between them and the other photochemical smog generation parameter e. g. ozone concentrations was discussed, because it is capable of analysing the water soluble ions as small as five min sampling of aerosol with the method mentioned above. There is positive correlation between ozone and sulfate ion, both of which are generated by photochemical reaction, and ammonium ion is also correlated well with sulfate ion. There is no correlation between ozone and nitrate ion. Measurement of ion balance indicate that sulfate ion exist as ammonium sulfate above Kanto area. In one flight, high concentration of sulfate appeared in the west part of the Sagami Bay and in the border of Tokyo Metropolitan and Saitama Prefectures.

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The ion chromatography with coulometric detection for the determination of inorganic cations was investigated, and applied to the determination of NH₄⁺ in a sample water under biological denitrification process for nitrogen removal, and of Ca²⁺ in a sample water under crystallization process for phosphorus removal. The inorganic cations (Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺, NH₄⁺, Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺) eluted from a cation fiber suppressor were monitored as the corresponding bases with conductometric detector (COND) and flow coulometric detector (FCD). In FCD, the electrochemical reaction of OH^- ion from the base with hydroquinone at a constant applied potential (+0.45 V vs. Ag-AgI) was used to monitor the cations. The mixture of Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺, and NH₄⁺ was separated from each other by elution with 3 mM HNO₃, and favorably monitored with FCD. The mixture of Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺ was separated from each other by elution with 2.5 mM HNO₃-2.5 mM m-phenylenediamine·2HCl, and favorably monitored with FCD. Although the calibration curves of strong basic cations such as Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺, Sr²⁺, and Ba²⁺ obtained with COND were linear over the concentration range (10100) ppm, those of the weak basic cations such as NH₄⁺, Mg²⁺, and Ca²⁺ were nonlinear probably because of low dissociation at higher concentrations. However, the good linear relationship was obtained over the same concentration range for all cations with FCD. This is the most striking character of FCD in ion chromatography of weak basic cations. This method was applied to the determination of NH₄⁺ and Ca²⁺ in several actual samples with satisfactory results.

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A study on interlaboratory comparison was undertaken by request from the Air Quality Bureau of Environment Agency, Japan, and the analytical reliability of ion chromatography by round robin tests and the comparison with the results by the conventional colorimetric or nephelometric methods were investigated. Choosing NO₃^- and SO₄^2- as the ions to be measured, using some standard solution and extract solution of atmospheric particulate matters and rainwater. The results by ion chromatography showed with well reproducibility and accuracy by using the same instrument and at the same laboratory, and the agreement of the interlaboratory was also good. In comparison with the results by ion chromatography and the conventional method, a good agreement was obtained for ion concentrations of (10100)μg ml^-1 and was not so well for ion concentrations below a few μg ml^-1 level. The good agreement and high precision were obtained for ion chromatography, but the poor agreement and precision were observed for the conventional method. It was demonstrated from these results that ion chromatography can be employed as a standard method to be an excellent analytical method for ions in atmospheric samples.

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The adsorption behavior of tungsten(VI) onto activated carbon was studied by using a column method. The result was compared with those of molybdenum(VI), chromium(VI) and other ions. The adsorption of tungsten(VI) shows remarkable pH-dependency, like that of molybdenum(VI) and chromium(VI). The adsorption-pH curves shift toward the higher pH in the following order: HClO₄ <HNO₃ < H₂SO₄< HCl. As much as 0.54 g of tungsten(VI) was adsorbed onto 5.0 g of activated carbon at pH 2.0, where the pH value was adjusted by using HNO₃. The amount of tungsten(VI) adsorbed was one half as large as that of molybdenum(VI) and 100 times larger than those of other metal ions such as chromium(VI) and copper(II) under the optimum conditions. Tungsten(VI) may be adsorbed in the forms of polymerized species. The adsorption of tungsten(VI) onto activated carbon was remarkably affected by the addition of 0.2 mol dm^-3 NaX( X = NO₃^-, ClO₄^-, Cl^- and SO₄^2-) solution. The amounts of tungsten (VI) adsorbed increased in the following order: NaClO₄ <NaNO₃ <Na₂SO₄ <NaCl at pH 2.0. The salt effect on the adsorption of tungsten(VI) may be ascribed to the effect of the anion on the equilibrium constant of the formation of the polymerized species and/or on the formation rate of the polymerized species. Ten percent of all the tungsten(VI) adsorbed was eluted by passing a 100 ml portion of 5.0 mol dm^-3 HNO₃ through the column packed with 5.0 g of activated carbon loaded with 0.41 g of tungsten(VI). The electron microscope photographs of activated carbon and activated carbon loaded with tungsten(VI) are also reported.

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A new method for the generation of acrolein standard gas has been described. It is based on the dehydration of glycerol by using potassium hydrogen sulfate as the catalyst. Comparing the results with formerly reported allyl alcohol oxidation method, the present method provides easier and much reproducible means for the preparation in the nanogram range.

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A simple and selective spectrophotometric method for the determination of chlorpheniramine maleate(CP) by complex formation with o-hydroxyhydroquinonephthalein(Qn.Ph.), titanium(IV) and fluoride in the presence of sodium dodecyl sulfate(SDS) has been established. A linear calibration curve was obtained over the concentration range 0 - 45 μg of CP in 10 ml. The apparent molar absorptivity was 6.5 × 10⁴ dm³ mol^-1 cm^-1 at 580 nm. The method was successfully applied to the determination of CP in multiple component drugs.

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The extraction of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Fe(III) was studied in water - chloroform system by using 5-(4-dodecylphenylazo)-8-hydroxyquinoline (DHQ) as chelate extraction agent. Both the equilibrium-determined metal extraction and the "extraction rate-controlled" metal extraction were treated. In the latter extraction, batch-wise procedure to effect rapid mixing and rapid separation of two immiscible phases ("rapid mix - rapid separate" concept) was adopted. A comparison of the metal extraction under rate-controlled conditions with that under equilibrium indicated that the metal selectivity was reversed for the two types of approach in the extraction of Ni(II), Co(II), and Zn(II).

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