Separator column bromide

Van Os et al. [41] achieved complete separations in 6min of l-30mg L 1 concentrations of bromide, chloride, nitrite, nitrate and sulphate using a Zipax SAX separation column, with eluent suppression and electrical conductivity detection [42], The necessary high pressure packing techniques for packing the separation column have been described [43], With sample pieconcentration, detection limits were reduced to about 5pg L 1 but calibration graphs for chloride and nitrate were not linear. Sodium adipate and 1.410 3M disodium succinate are used as eluants, both at pH7. 

When using conventional ion chromatographic separation techniques, it is possible that other matrix anions also common to non saline waters may coelute with bromide. For example, bromide and nitrate elute simultaneously using a standard anion separator column (Dionex No. 30065), standard anion suppressor (Dionex No. 30366) and standard eluant (0.003M sodium bicarbonate/0.0024M sodium carbonate). 

Ion chromatographic methods have been described for the co-determination of anions and cations in rainwater. Thus Jones and Tarter [138], using the conditions given in Table 2.19 reported determinations down to lmg L 1 of anions (chloride, bromide and sulphate) and cations (sodium, potassium, magnesium and calcium) in rainwater without converting the cations to anion complexes prior to detection [139], The technique uses a cation separator column, a conductivity detector, an anion suppressor column, and either a second conductivity detector or an electrochemical detector in sequence. The use of different eluants provides a means for the detection of monovalent cations and anions and divalent cations and anions in each of the samples. Using an eluant with a basic pH, it is possible to separate simultaneously and detect the monovalent cations (with the exception of the ammonium ion) and anions, while an eluant with an acidic pH allows for the separation and detection of divalent cations and anions. 

Jones and Tarter [11] have applied this technique to the simultaneous determination of metals (sodium, potassium, calcium, magnesium) and anions (chloride, sulphate, nitrate, bromide) in potable waters. The technique uses a cation separator column, a conductivity detector, an anion separator column and an anion suppressor column. Two different eluants were used lithium carbonate-lithium acetate dihydrate, and copper phthalate. 

The suspension is stirred and cooled in an ice bath while 12.0 g (0.070 mol) of benzyl bromide (Note 5) is added over ca. 5 min. The ice bath is removed, and the mixture is allowed to stir for 18 hr at room temperature (Note 6). The suspension is filtered through Celite, the filter cake is washed with two 50-mL portions of toluene, and the combined filtrates are evaporated under reduced pressure. The remaining liquid, which weighs 9.6-10.4 g, is dissolved in 15 mL of 5% tetrahydrofuran in hexane. The cloudy solution is applied to a 5 x 47.5 cm column prepared with 380-385 g of silica gel (Note 7) packed in 5% tetrahydrofuran in hexane. The column is eluted with 5% tetrahydrofuran in hexane, and 250-mL fractions are collected and analyzed by TLC (Note 8). A total of 12 or 13 fractions (3-3.25 L) is collected first to separate benzyl bromide, dibenzyl ether, and other minor by-products. The product is then eluted with 0.5-1.0 L of tetrahydrofuran, the solvent is evaporated, and the remaining 6.0-6.5 g of liquid is distilled under... 

At present, ten different anion exchangers (IonPac AS1 to AS7) with diverse selectivities are available from Dionex. The structural and technical characteristics of these separator columns are summarized in Table 3-4. Additionally, special columns for the fast separation of simple inorganic anions, for the separation of bromide, nitrate, and chlorate, as well as for the anion exchange chromatography of amino acids are available. 

Fig. 3-44. Chromatogram of inorganic anions according to DIN 38405, part 19 [55], - Separator column IonPac AS4A eluent 0.0017 mol/L NaHC03 + 0.0018 mol/L Na2C03 flow rate 2 mL/min detection suppressed conductivity injection 50 pL solute concentrations 3 ppm fluoride, 4 ppm chloride, 10 ppm nitrite, 10 ppm bromide, 20 ppm nitrate, 10 ppm orthophosphate, and 25 ppm sulfate.

For the detection of mineral acids in the presence of an excessive amount of nitrate, the IonPac AS2 separator column was developed from which bromide and nitrate elute after sulfate. The selectivity of this stationary phase is based on the hydrophobic properties of the exchange groups bound to the latex beads (see Section 3.3.1.2). As shown in Fig. 3-47, small quantities of chloride, orthophosphate, and sulfate can be determined in the presence of high amounts of nitrate. The best separation is obtained with an eluent mixture of sodium carbonate and sodium hydroxide. 

Fig. 3-63. Separation of inorganic anions using p-hydroxybenzoic add as the eluent. - Separator column Wescan 269-029 eluent 0.004 mol/L PHBA, pH 8.7 flow rate 1.5 mL/min detection direct conductivity injection volume 100 pL solute concentrations 5 ppm fluoride, chloride, nitrite, bromide, and nitrate, and 10 ppm orthophosphate and sulfate.

Fig. 3-86. Comparison between the retention behavior of inorganic anions and several organic carboxylic acids, respectively. - Separator column IonPac AS4 eluent 0.0028 mol/L NaHC03 + 0.0022 mol/L Na2C03 flow rate 1.6 mL/min detection suppressed conductivity injection 50 pL solute concentrations a) 1.5 ppm fluoride (1), 2 ppm chloride (2), 5 ppm orthophosphate (3) and bromide (4), 10 ppm nitrate (5), and 12.5 ppm sulfate (6), b) 5 ppm formic acid (7), 40 ppm benzoic acid (8), 20 ppm succinic acid (9), 10 ppm malonic acid (10), 20 ppm maleic acid (11), tartaric acid (12), and oxalic acid (13).

Fig. 3-127. Separation of various inorganic anions with an isoconductive eluent. - Separator column Waters IC-PAK Anion eluent see Table 3-23 (eluent switching at the time of injection) detection direct conductivity injection volume 100 pL solute concentrations 1 ppm fluoride (1), 2 ppm carbonate (2) and chloride (3), 4 ppm nitrite (4), bromide (5), and nitrate (6), 6 ppm orthophosphate (7), 4 ppm sulfate (8) and oxalate (9), 10 ppm chromate (10), and molybdate (11) (taken from [135]).

Fig. 5-13. Ion-pair chromatographic separation of inorganic anions on a chemically bonded reversed phase. — Separator column LiChrosorb RP 18 (10 xm) eluent 0.002 mol/L TBAOH + 0.05 mol/L phosphate buffer (pH 6.7) flow rate 2 mL/min detection direct conductivity injection volume 20 pL solute concentrations 1000 ppm each of fluoride, chloride, sulfate, nitrite, bromide, dichromate, and nitrate (taken from [26]).

Fig. 5-14. Ion-pair chromatographic separation of inorganic anions with indirect photometric detection. — Separator column Waters C,% Radial-PAK (5 pm) eluent 0.0004 mol/L tetrabutylam-monium salicylate (pH 4.62) flow rate 2 mL/min detection UV (288 nm, indirect) injection volume 50 pL solute concentrations 4 ppm orthophosphate, 2 ppm chloride, 4 ppm nitrite, bromide, nitrate and iodide, 6 ppm sulfate, and 6 ppm thiosulfate (taken from [28]).

Fig. 5-44. Separation of a didodecyl-dimethylammonium bromide. -Separator column IonPac NS1 (10 pm) eluent (A) 0.02 mol/L HC1 / acetonitrile (25 75 v/v) flow rate 1 mL/min detection suppressed conductivity injection volume 50 pL solute concentration 300 ppm.

Fig. 6-16. Indirect photometric detection of various inorganic anions. - Separator column 250 mm x 4 mm I.D. SAR-40-0.6 eluent 0.001 mol/L sodium phthalate (pH 7 to 8) flow rate 2 mL/min detection UV (285 nm, indirect) injection volume 20 pL solute concentrations 106 ppm chloride, 138 ppm nitrite, 400 ppm bromide, 310 ppm nitrate, and 480 ppm sulfate (taken from [29]).

Fig. 8-7. Separation of chlorite and chlorate from other mineral acids. - Separator column IonPac AS9 eluent 0.00075 mol/L NaHCO-, + 0.002 mol/L Na2C03 flow rate 1 mL/min detection suppressed conductivity injection 50 pL solute concentrations 5.6 ppm fluoride, 0.5 ppm chlorite, 45.4 ppm chloride, 0.06 ppm nitrite, 0.08 ppm bromide, 0.14 ppm chlorate, 42.1 ppm nitrate, 0.17 ppm orthophosphate, and 5 ppm sulfate.

Fig. 8-48. On-line determination of mineral acids and silicate. - Separator columns 2 IonPac AS4A concentrator columns (A) TAC-1, (B) IonPac AG5 eluent (A) 0.0017 mol/L NaHC03 + 0.0018 mol/L Na2C03, (B) 0.015 mol/L H3B03 + 0.015 mol/L NaOH flow rate (A) 2 mL/min, (B) 1 mL/min detection (A) suppressed conductivity, (B) photometry at 410 nm after reaction with sodium molybdate concentrated volume 23 mL solute concentrations 10 ppb fluoride, 10 ppb chloride, 10 ppb bromide, 10 ppb nitrate, 20 ppb orthophosphate, 20 ppb sulfate, and 23 ppb silicate (taken from [36]).

Fig. 8-104. Analysis of bromide and sulfate in brine. — Separator column IonPac AS4A elu-,, t ent 0.0017 mol/L NaHC03 + 0.0018 mol/L...

Detection in CE takes place directly on the separation column. The UV/Vis photometric detection is most common in capillary electrophoresis, as it is simple and reliable. The problems connected with the detection of LMW ions are caused by their low absorption in the UV region. Therefore, direct UV detection is only applicable to a few inorganic anions, e.g., to nitrate, sulfide, nitrite, iodide, bromide, and thiocyanate (for example, a detection limit of lOpgl has been attained for sulfide in waste water using direct UV detection at 229 nm). LMW carboxylic acids can be detected at low wavelengths (200 nm and below). 

As pointed out above, fused silica used as a material for separation columns in capillary electrophoretic methods has normally a negative charge. Various ions, especially surfactants or big amphoteric ions, can be, however, adsorbed on the surface, which dramatically influences the zeta potential. For example, the addition of a small concentration of a suitable cationic surfactant like tetradecyltrimethylammonium bromide to the BGE causes its adsorption at the inner capillary wall and the reversal of the EOF in silica capillaries to the anodic side. Such surfactants are... 

Figure 3.140 Separation of inorganic anions detection nonsuppressed conductivity injec-using a potassium hydrogen phthalate eluent, tion volume 10pL peaks lOOmg/L each of Separator column Waters IC-PAK Anion elu- fluoride (1), chloride (2), nitrite (3), bromide ent 1 mmol/L KHP, pH 7 flow rate 2 mlVmin (4), nitrate (5), sulfate (6), and iodide (7).

Figure 8.46 Determination of disinfection byproduct anions and bromide in ozonated bottled water using US EPA Method 326.0. Separator column lonPac AS19 column dimensions 250 mm x 4 mm i.d. column temperature 30 °C eluent KOH (EG) gradient lOmmol/L isocratically for 10 min and then linearly to 45 mmol/L in 15 min flow rate ...

Figure 10.1 Conventional and fast isocratic separation of anions in municipal drinking water, (a) Separator column lonPac AS22 column dimensions 250 mm x4 mm i.d. column temperature ambient eluent 4.5 mmol/L Na2COs -I-1.4 mmol/L NaHCOs flow rate 1.2mL/min detection suppressed conductivity injection volume 25 pL peaks 0.19mg/L fluoride (1), 98.1 mg/L chloride (2), 0.54mg/L nitrite (3), 1.22 mg/L bromide (4), 2.43 mg/L nitrate (5), 3.12 mg/L orthophosphate (6), and...

Figure 10.29 Separation of chlorite, bromate, bromide, and chlorate at trace levels in reagent water and spiked tap water using EPA Method 317.0 with a high-capacity hydroxide-selective anion exchanger. Separator column lonPac AS19 with guard column dimensions 250mm X4 mm i.d. column temperature ...

Figure 10.52 Separation of bromide and iodide in a KCI matrix using a KCI eluent and UV detection. Separator column lonPac AS9-SC with guard column dimensions 250mm x 4 mm i.d. eiuent 30 mmol/L KCI flow rate ...

Figure 10.157 Analysis of chloride, bromide, and sulfate in a nickel sulfamate bath. Separator columns 2 lonPac AS4A eluent 1.7 mmol/ L NaHCOa -I-1.8 mmol/L Na2C03 flow rate I.SmlVmin detection suppressed...

Figure 10.272 Separation of chloride and bromide counterions in a multisymptom cold/flu medication. Separator column lonPac ASM column dimensions 250 mm x 4 mm i.d. eluent 35mmol/L Na2CO3-l-0.8mmol/L NaHCOi flow rate 1.2miymin detection suppressed...

Figure 10.366 Determination of fluoride, chloride, and bromide in a liquid crystal material after oxidative UV photolysis. Separator column ionPac AS16 column temperature 25°C eluent NaOH, linear gradient from 5 to 100 mmol/L flow rate 1 mlVmin detection suppressed conductivity injection volume ...

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