Fast analysis of thiocyanate by ion-pair chromatography using a silica-based monolithic column and direct conductivity detection was carried out. Chromatographic separation was performed on a Chromolith Speed ROD RP-1...Fast analysis of thiocyanate by ion-pair chromatography using a silica-based monolithic column and direct conductivity detection was carried out. Chromatographic separation was performed on a Chromolith Speed ROD RP-18e using tetrabutylammonium hydroxide (TBA)-phthalic acid-acetonitrile as eluent. The effects of eluent concentration, eluent pH value, column temperature and flow rate on retention time of thiocyanate were investigated. The optimized chromatographic conditions for the determination of thiocyanate were as follows: 0.25 mmol/L TBA-0.18 mmol/L phthalate-7% acetonitrile (pH 5.5) as eluent, column temperature of 30 ℃, and flow rate of 6.0 mL/min. Retention time of thiocyanate was less than 1 min under the conditions. Common anions (Cl^-, NO3 , SO42 and I^- ) did not interfere with the determination of thiocyanate. Detection limit (S/N = 3) of thiocyanate was 0.96 mg/L. Calibration graph between peak area and the concentration of thiocyanate was linear in the range of 2.0- 100.0 mg/L. Relative standard deviation (RSD) of chromatographic peak area was 1.4% (n = 5). This method has been applied to the determination of thiocyanate in ionic liquids. Recoveries of thiocyanate after spiking were 100.5%.展开更多
研究了用硅胶整体柱和直接电导检测的离子对色谱快速分析高氯酸盐的方法。实验采用Chromolith Speed ROD RP-18e色谱柱,以氢氧化四丁铵(离子对试剂)+邻苯二甲酸+乙腈(有机改进剂)为淋洗液,讨论了离子对试剂浓度、有机改进剂浓度...研究了用硅胶整体柱和直接电导检测的离子对色谱快速分析高氯酸盐的方法。实验采用Chromolith Speed ROD RP-18e色谱柱,以氢氧化四丁铵(离子对试剂)+邻苯二甲酸+乙腈(有机改进剂)为淋洗液,讨论了离子对试剂浓度、有机改进剂浓度、pH、色谱柱温度和流速对ClO4^-保留时间的影响。确定最佳色谱条件为:0.25mmol/L氢氧化四丁铵+0.18mmol/L邻苯二甲酸+7%乙腈(pH5.5)作为淋洗液,柱温30℃,流速6.0mL/min。在此条件下,ClO4^-的保留时间在1min之内。其它常见阴离子(Cl^-、NO3^-、SO4^2-和I^-)不干扰测定。方法的检出限为1.56mg/L;工作曲线的线性范围是2.4~100mg/L;峰面积的相对标准偏差(RSD,n=5)为1.9%。将本方法应用于测定加标果汁和加标地下水中的ClO4^-,加标回收率分别为98.2%和97.6%。展开更多
基金supported by the Program for Scientifc and Technological Innovation Team Construction in Universities of Heilongjiang Province (No. 2011TD010)
文摘Fast analysis of thiocyanate by ion-pair chromatography using a silica-based monolithic column and direct conductivity detection was carried out. Chromatographic separation was performed on a Chromolith Speed ROD RP-18e using tetrabutylammonium hydroxide (TBA)-phthalic acid-acetonitrile as eluent. The effects of eluent concentration, eluent pH value, column temperature and flow rate on retention time of thiocyanate were investigated. The optimized chromatographic conditions for the determination of thiocyanate were as follows: 0.25 mmol/L TBA-0.18 mmol/L phthalate-7% acetonitrile (pH 5.5) as eluent, column temperature of 30 ℃, and flow rate of 6.0 mL/min. Retention time of thiocyanate was less than 1 min under the conditions. Common anions (Cl^-, NO3 , SO42 and I^- ) did not interfere with the determination of thiocyanate. Detection limit (S/N = 3) of thiocyanate was 0.96 mg/L. Calibration graph between peak area and the concentration of thiocyanate was linear in the range of 2.0- 100.0 mg/L. Relative standard deviation (RSD) of chromatographic peak area was 1.4% (n = 5). This method has been applied to the determination of thiocyanate in ionic liquids. Recoveries of thiocyanate after spiking were 100.5%.
文摘研究了用硅胶整体柱和直接电导检测的离子对色谱快速分析高氯酸盐的方法。实验采用Chromolith Speed ROD RP-18e色谱柱,以氢氧化四丁铵(离子对试剂)+邻苯二甲酸+乙腈(有机改进剂)为淋洗液,讨论了离子对试剂浓度、有机改进剂浓度、pH、色谱柱温度和流速对ClO4^-保留时间的影响。确定最佳色谱条件为:0.25mmol/L氢氧化四丁铵+0.18mmol/L邻苯二甲酸+7%乙腈(pH5.5)作为淋洗液,柱温30℃,流速6.0mL/min。在此条件下,ClO4^-的保留时间在1min之内。其它常见阴离子(Cl^-、NO3^-、SO4^2-和I^-)不干扰测定。方法的检出限为1.56mg/L;工作曲线的线性范围是2.4~100mg/L;峰面积的相对标准偏差(RSD,n=5)为1.9%。将本方法应用于测定加标果汁和加标地下水中的ClO4^-,加标回收率分别为98.2%和97.6%。