Papers by Keyword: Ion Chromatography

Abstract: An ion chromatographic method for determination of bromide and bromate in the presence of standard anions in drinking water was described. The method was based on separation on Metrosep A Supp 7-250 (250 x 4 mm) column with 3.6 mmol/L Na₂CO₃ as eluent and conductivity detection after sequential chemical and carbon dioxide suppression. The influence of flow rate and column temperature was studied and optimal experimental conditions for simultaneous determination of eight anions were chosen. Analytical characteristics of the ion chromatographic method were assessed for simultaneous determination of bromide, bromate, fluoride, chloride, nitrate, nitrite, phosphate and sulfate. The calibration curves were linear (r²=1, N=7) in the concentration ranges: 0.4-12 mg/L BrO₃^- and 0.3-11 mg/L Br^-. Recovery test was performed on a spiked certified reference material for soft drinking water. The obtained recoveries for bromate and bromide were 96.0 and 101.0 %, respectively. The repeatability and intermediate precision were between 5.1 and 0.14 % (RSD) depending on the analytes concentration. The limits of detection were 20 μg/L BrO₃^- and 10 μg/L Br^-

Abstract: A fast and accurate method for simultaneous determination of the content of fluorine and chlorine in inorganic thermal insulation materials by ion chromatography was developed. The samples were cut into pieces of weight less than 40mg, washed with water as the extractant, heated for 30 min and then centrifuged, filtered through a 0.22 μm microporous membrane, and the cation was removed using a SEP-H column. The solution was rinsed with 20/30 mM KOH as the mobile phase, separated by anion exchange column and then detected using a conductivity detector. The mass concentration of fluorine and chlorine in the range of 0.1-10mg/L was linearly related to their peak area, the detection limit of fluorine was 0.030mg/Land the detection limit of chlorine was 0.016mg/L. The relative standard deviations (n=6) of the three typical inorganic insulating materials (glass wool, rock wool and mineral wool) were less than 2.0% and the rate of recovery of fluoride and chloride ion was between 97% and 101%.The method had good accuracy and recovery rate. The absolute error of the measured value between ion chromatography and the national standard was less than 0.20%.The results showed that the method was suitable for the determination of the content of fluorine and chlorine in inorganic thermal insulation materials

Abstract: A quantitative ion chromatographic analytical method for the determination of fluorine in fluorocarbon coatings is proposed. The extraction of the anions from the samples was performed using potassium hydroxide after centrifugation drying to dissolved at preference temperature. Using H column to remove large amounts of potassium ions in the solution。In paper describe the observed limits of detection and of quantitation in mg kg^-1 and the mean relative standard deviation in percent This method is simple operation, less interference factors, fast analysis speed, the determination results accurate and reliable, with good repeatability and reproducibility.

Abstract: A quantitative ion chromatographic analytical method for the continuous determination of the sulfite and sulfide in gypsum and gypsum products is proposed. This paper established a determination method removal interference with each other between sulfite and sulfide that measure sulfite and sulfide content respectively. A set of calibration graphs for standards with different concentration ranges with indicate a good linear regression.The method presents good repeatability because in all cases the observed RSD was below 1% through two chromatographic parameters both of the retention time and the area of the analytical signal. The accuracy of the method was evaluated through recovery assays. The recoveries varied from93.9% to 105.7% depending on the anion, indicating that the extraction of the analytes was good enough to de used for the determination of the studied anions in gypsum sample.

Abstract: Sulfuric Peroxide Mixture (SPM) showed excellent cleaning efficiency for organic contamination as well as metal or metal oxide particles on photomask surface. In order to reduce haze formation during litho process for ArF photomask, it is necessary to remove any ion sources on photomask, such as sulfate ion, ammonium ion, etc. In this paper we reported a new cleaning method, treating photomask with 172nm UV followed by hot DI rinse, reduces residual sulfate ion in MoSiN_xO_y surface and quartz surface by 50% and 80% respectively comparing to traditional cleaning process. We believe that this new process has the potential to greatly alleviate the haze issue caused by sulfate ion and helps increase the lifetime of photomasks

Abstract: A method was developed for the determination of inorganic and total fluoride in Antarctic krill by using Ultrasonic Extraction and Ion Chromatography (IC). The analyte is separated by the anion exchange column AS-15 and detected with the conductive detector. The linear range of the calibration curve for fluorinion was 0.25 mg/L to 10 mg/L with a correlation coefficient of 0.9993, and the recovery of this method was 89.62% to 103.91%, and the RSD was lower than 7.09%, the LOD of this method was 0.008 mg/L and LOQ was 0.025 mg/L. Both inorganic and total fluoride in Antarctic krill were higher than GB 2762-2005, but they all much lower than ever reported.

Abstract: Ion chromatography (IC) method was applied to detection of fluorine in the atmosphere calm wind conditions at the area around the yellow phosphorus enterprise. The results indicated that the recovery of standard addition of Fluroide is 96.7%~100.6%. It gives a linear response of chromatographic peak height with respect to the fluoride in the range of 1~25 μg/mL, and the coefficient correlations R value is 0.9994. The concentration of Fluorine in the surrounding of yellow phosphorus enterprise ranging from 100~1500 m varies from 0.641~0.070 mg/m³. The relative standard deviation (RSD) of this method is between 2.10%~0.50%. This method is sensitivity and selectivity, low disturbance, and it is considered as a promising method for the detection of Fluorine surrounded yellow phosphorus enterprise.

Abstract: A simple, rapid and accurate method for the determination of fluoride in Antarctic krill has been developed. The fluoride content in Antarctic krill was determined by ion chromatography. The method requires a simple sample clean-up procedure to remove the interfering Cl^- from the hydrochloric acid extraction solution. The optimum extraction conditions of fluoride from Antarctic krill samples were obtained by adding 8mL of 1:11(v/v) hydrochloric acid solution and extracting for 60 min. Under these conditions, recoveries of fluoride from Euphausia superba and Penaeus vannamei were 97.9-105.6% and 95.1-101.9%, respectively. The limit of detection was 0.01mg/kg. The method was applied to the determination of fluoride in Antarctic krill. Key words: Fluoride, Antarctic krill, Ion chromatography

Abstract: The degradation rules of glycan in reed ethanol/water cooking process were studied. The degradation rules of polydextrose and polyxylose were obtained in the cooking process by means of ion chromatography determination of glucose and xylose in the reed ethanol pulp content under different holding time. Results showed that cellulose (polydextrose) removal rate obviously was divided into two stages, rapid removal stage at the holding time of 0-90min and slow removal stage at the holding time of 90-210min; hemicellulose (xylan) removal rate was also divided into two stages, slow removal stage at the holding time of 0-60 min and rapid removal stage at the holding time from 60min until the end; meanwhile the change rules of lignin and ash content were achieved.

Abstract: In this study, the high performance ion chromatography integrated pulsed amperometric detection (HPIC-IPAD) was appliedfor the first time to detect 10 sulfonamides. In this experiment,we used Dionex AS18 (250mm×2mm) and AG18 (50mm×2mm) columnsfilled with an anion exchange resin, with 14 mmol / L NaOH solution concentration. The Analysis temperature was 30 ° C, the flow rate was 0.25 mL / min, and the injection volume was 10 μL. The detection was through pulsed amperometric detection cell with Au electrode and reference electrode pH-Ag/AgCl as working electrodes. Take the standard stock solution compounding 0.06,0.15,0.30,1.5,3.0 mg / L standard solutions respectively,build linear regression on chromatographic peak area as Y and analyte mass concentration of as X (mg / L). In the range of 0.06-3.0 mg / L, the 10 sulfonamides response appeared a linear relationship (R> 0.9989). This method can be considered for the detection of trace sulfonamides substances in cosmetics, food, and feed.