【仪电分析】顶空-气相色谱法测定生活饮用水中 27种卤代烃

智能文字提取功能测试中

【仪电分析】顶空-气相色谱法测定生活饮用水中27种卤代烃挥发性卤代烃通常指沸点在200℃以下的卤代烃，具有致畸、致癌、易在人体内蓄积等特点，《生活饮用水卫生标准》GB5749-2022对环境水样中卤代烃的含量进行了严格限定。本方案参考GB/T 5750.8-2023 《生活饮用水标准检验方法 第8部分：有机物指标》的4.3 顶空毛细柱气相色谱法，本方法适用于生活饮用水中27种挥发性有机物的测定。一、主要仪器和试剂1）气相色谱GC128，配ECD检测器； 2）全自动顶空装置；3）DB-624毛细柱，30m×0.25mm×1.4μm；4）27种卤代烃标准溶液；5）氯化钠：优级纯，马弗炉550℃烘烤2小时；6）甲醇：色谱纯；7）般实验室常用仪器和设备。二、实验方法2.1 气相色谱参考条件进样口温度：250℃；柱流量：0.8ml/min；分流比：1:1；程序升温：45℃（5min）→10℃/min→100℃→20℃/min→240℃（10min）；检测器条件：温度300℃； ECD选项：量程10e0、电流0.5nA、电流调节×12.2 顶空参考条件平衡温度：70℃；定量管温度：90℃；传输线温度：90℃；平衡时间15min；加压时间0.2min；取样时间0.2min；定量环平衡时间0.1min；进样时间0.2min。顶空进样系统采用高速振荡模式；2.3 标准系列的制备 取7个50 mL容量瓶，预先加入适量超纯水，再分别依次加入适量的27种混合卤代烃标准使用液，配制成7个浓度点的标准系列，各组分质量浓度见下表1。取7个顶空瓶，分别称取3.7g氯化钠于顶空瓶种，加入各混合标准系列溶液10mL，立刻密封顶空瓶，轻轻摇匀后上机测试。表1 混合标准系列溶液质量浓度序号组分有证标准溶液mg/L混合标准系列溶液质量浓度（μg/L）123456711,1-二氯乙烯60.82.436.0812.224.336.548.660.82二氯甲烷 44617.844.689.21782683574463反-1,2-二氯乙烯61524.661.51232463694926154顺-1,2-二氯乙烯89335.789.31793575367148935三氯甲烷11.30.4531.132.264.536.799.0611.361,1,1-三氯乙烷5.210.2080.5211.042.083.134.175.217四氯化碳1.600.0640.1600.3200.6400.9601.281.6081,2-二氯乙烷67226.967.21342674035386729三氯乙烯12.60.5041.262.525.047.5710.112.610二氯一溴甲烷15.10.6041.513.026.049.0612.115.111反-1,2-二溴乙烯22.70.9082.274.549.0813.618.222.712顺-1,2-二溴乙烯22.70.9082.274.549.0813.618.222.7131,1,2-三氯乙烷1767.0417.635.270.410514117614四氯乙烯3.520.1410.3520.7041.412.112.823.5215一氯二溴甲烷28.31.132.835.6611.317.022.628.316三溴甲烷56.52.265.6511.322.633.945.256.5171,3-二氯苯1526.0915.230.460.991.3122152181,4-二氯苯32112.832.164.2128193257321191,2-二氯苯1877.4818.737.474.8112150187201,3,5-三氯苯19.80.7921.983.967.9211.815.819.8211,2,4-三氯苯29.61.182.965.9211.817.823.729.622六氯丁二烯2.710.1080.2710.5421.081.632.172.71231,2,3-三氯苯17.30.6921.733.466.9210.413.817.3241,2,4,5-四氯苯11.20.4481.122.244.486.728.9611.2251,2,3,4-四氯苯10.30.4121.032.064.126.188.2410.326五氯苯4.900.1960.4900.9801.962.943.924.9027六氯苯7.410.2960.7411.482.964.455.937.412.4样品处理 采样时先加0.3-0.5g抗坏血酸于棕色磨口玻璃瓶中，将水样沿瓶壁缓慢加入瓶中。测试前顶空瓶中加入3.7g氯化钠，准确移入10mL水样，立即密封顶空瓶，轻轻摇匀。三、实验结果3.1 标准色谱图图1 混合标准溶液色谱图1_1,1-二氯乙烯2_二氯甲烷3_反-1,2-二氯乙烯4_顺-1,2-二氯乙烯5_三氯甲烷6_1,1,1-三氯乙烷7_四氯化碳8_1,2-二氯乙烷9_三氯乙烯10_二氯一溴甲烷11_反-1,2-二溴乙烯12_顺-1,2-二溴乙烯13_1,1,2-三氯乙烷14_四氯乙烯15_一氯二溴甲烷16_三溴甲烷17_1,3-二氯苯18_1,4-二氯苯19_1,2-二氯苯20_1,3,5-三氯苯21_1,2,4-三氯苯22_六氯丁二烯23_1,2,3-三氯苯24_1,2,4,5-四氯苯25_1,2,3,4-四氯苯26_五氯苯27_六氯苯3.2标准曲线表2  27种卤代烃标准工作曲线序号组分标准工作曲线线性相关系数11,1-二氯乙烯y=49371.2+25163*x0.99882二氯甲烷 y=9687.15+3623.24*x0.99913反-1,2-二氯乙烯y=36682.5+3341.03*x0.99944顺-1,2-二氯乙烯y=11775.4+1932.32*x0.99985三氯甲烷y=20401.2+203572*x0.999461,1,1-三氯乙烷y=51536.4+640094*x0.99897四氯化碳y=59747.7+2609460*x0.999081,2-二氯乙烷y=-4332.06+2249.22*x0.99929三氯乙烯y=38521.8+343992*x0.999410二氯一溴甲烷y=-293894+956524*x0.998111反-1,2-二溴乙烯y=18724.9+209390*x0.999612顺-1,2-二溴乙烯y=63229.7+191253*x0.9999131,1,2-三氯乙烷y=81346.7+21722*x0.998614四氯乙烯y=25840.3+1.312e+006*x0.999015一氯二溴甲烷y=-451951+575263*x0.997316三溴甲烷y=-186324+150550*x0.9981171,3-二氯苯y=-1822.91+25736.2*x0.9990181,4-二氯苯y=92144.8+10735.5*x0.9986191,2-二氯苯y=-10512.5+19617.8*x0.9993201,3,5-三氯苯y=60421.8+184883*x0.9995211,2,4-三氯苯y=25875.5+126479*x0.999422六氯丁二烯y=59624+1677060*x0.9989231,2,3-三氯苯y=18664.7+188932*x0.9992241,2,4,5-四氯苯y=-511.239+188808*x0.9993251,2,3,4-四氯苯y=-9697.04+318369*x0.998726五氯苯y=70081.9+407399*x0.999227六氯苯y=23423.8+283344*x0.99993.3 精密度与正确度以超纯水为空白，取洁净容量瓶，加入适量混合标准使用溶液，配置不同浓度的人工合成水样。各浓度相对标准偏差及平均回收率数据见下表3-4。表3 低浓度人工合成水样平均回收率及相对标准偏差序号组分加标μg/L人工合成水样测试结果（μg/L）RSD(%)回收率范围(%)12345611,1-二氯乙烯3.653.153.233.313.383.33.322.4586.3~92.62二氯甲烷26.823.823.323.523.424.325.23.0686.9~94.03反-1,2-二氯乙烯36.933.533.334.135.034.935.12.3390.2~95.14顺-1,2-二氯乙烯53.650.851.452.754.252.053.02.3394.8~1015三氯甲烷0.6790.6610.6360.6310.6480.6290.6612.2692.6~97.361,1,1-三氯乙烷0.3130.2790.2810.2790.2950.2830.2912.3889.1~94.27四氯化碳0.0960.0910.0920.0960.1000.0950.0894.1992.7~10481,2-二氯乙烷40.340.241.139.739.441.540.12.0197.8~1039三氯乙烯0.7570.7420.7130.7140.7380.7140.7462.1794.2~98.510二氯一溴甲烷0.9060.9090.9160.9270.9010.9550.9162.0599.4~10511反-1,2-二溴乙烯1.361.161.171.161.221.161.243.0485.3~91.212顺-1,2-二溴乙烯1.361.271.181.151.211.171.213.5284.6~93.4131,1,2-三氯乙烷10.68.849.269.359.689.429.633.2683.4~91.314四氯乙烯0.2110.2110.2160.2100.2090.1990.2162.9994.3~10215一氯二溴甲烷1.961.701.721.721.711.681.720.9485.7~87.816三溴甲烷3.393.033.163.133.23.193.262.4889.4~96.2171,3-二氯苯9.138.758.348.338.348.678.382.2491.2~95.8181,4-二氯苯19.316.417.417.51817.718.64.1985.0~96.4191,2-二氯苯11.29.849.769.7910.49.9410.84.2387.1~96.4201,3,5-三氯苯1.190.9860.9910.9840.9961.090.9814.1782.4~91.6211,2,4-三氯苯1.781.571.531.531.471.481.492.5282.6~88.222六氯丁二烯0.1630.1610.1580.1610.1580.1570.1662.0896.3~102231,2,3-三氯苯1.041.081.061.061.061.081.022.0598.1~104241,2,4,5-四氯苯0.6720.6860.6330.6340.6870.6830.6533.8994.2~102251,2,3,4-四氯苯0.6180.6130.6090.6370.6010.6190.6161.9797.2~10326五氯苯0.2940.2740.2830.2840.2690.2970.2743.5891.5~10127六氯苯0.4450.4240.4220.4040.4030.4050.4132.2890.6~95.3表4 中浓度人工合成水样平均回收率及相对标准偏差序号组分加标μg/L人工合成水样测试结果（μg/L）RSD(%)回收率范围(%)12345611,1-二氯乙烯18.217.416.817.718.716.917.53.9192.3~1032二氯甲烷1341361361341391281342.7395.5~1043反-1,2-二氯乙烯1851871781821941751803.7694.6~1054顺-1,2-二氯乙烯2682692632602722512632.7993.7~1025三氯甲烷3.403.373.613.583.733.473.603.5099.1~11061,1,1-三氯乙烷1.561.531.441.481.591.431.493.9991.7~1027四氯化碳0.4800.4520.4410.4610.4480.4430.4692.4091.9~97.781,2-二氯乙烷2022032092002031912012.9294.6~1049三氯乙烯3.783.723.533.643.853.493.673.5892.3~10210二氯一溴甲烷4.534.414.434.334.394.164.392.2991.8~97.811反-1,2-二溴乙烯6.816.796.746.676.846.46.742.3394.0~10012顺-1,2-二溴乙烯6.816.606.716.486.556.316.592.0792.7~98.5131,1,2-三氯乙烷52.851.453.150.850.549.251.22.5093.2~10114四氯乙烯1.060.9961.020.9820.9930.9780.9971.4892.3~96.215一氯二溴甲烷8.498.488.708.338.418.068.572.6194.9~10316三溴甲烷17.017.617.317.117.416.716.82.0498.2~104171,3-二氯苯45.742.642.040.542.644.042.52.6788.6~96.3181,4-二氯苯96.392.693.089.790.189.589.31.8292.7~96.6191,2-二氯苯56.155.656.755.156.152.956.72.5794.3~101201,3,5-三氯苯5.945.595.575.615.705.355.82.6990.1~97.6211,2,4-三氯苯8.888.728.858.658.678.438.81.6994.9~99.722六氯丁二烯0.8130.7830.7450.7740.7960.7410.7822.8991.1~97.9231,2,3-三氯苯5.195.145.295.155.065.035.121.7796.9~102241,2,4,5-四氯苯3.363.193.383.353.333.223.352.3794.9~101251,2,3,4-四氯苯3.093.063.173.072.982.953.012.5895.5~02.626五氯苯1.471.391.341.321.351.291.443.9387.8~98.027六氯苯2.212.212.062.052.192.112.033.6091.4~99.53.4样品测试对饮用水样品进行测试，平行测定3次，样品测试结果如表5。表5 样品平行测试结果序号组分样品1（μg/L）样品2（μg/L）样品3（μg/L）平均结果（μg/L）11,1-二氯乙烯NDNDNDND2二氯甲烷 NDNDNDND3反-1,2-二氯乙烯NDNDNDND4顺-1,2-二氯乙烯NDNDNDND5三氯甲烷1.191.211.031.1461,1,1-三氯乙烷NDNDNDND7四氯化碳NDNDNDND81,2-二氯乙烷NDNDNDND9三氯乙烯NDNDNDND10二氯一溴甲烷0.230.250.210.2311反-1,2-二溴乙烯NDNDNDND12顺-1,2-二溴乙烯NDNDNDND131,1,2-三氯乙烷NDNDNDND14四氯乙烯NDNDNDND15一氯二溴甲烷0.120.130.120.1216三溴甲烷NDNDNDND171,3-二氯苯NDNDNDND181,4-二氯苯NDNDNDND191,2-二氯苯NDNDNDND201,3,5-三氯苯NDNDNDND211,2,4-三氯苯NDNDNDND22六氯丁二烯NDNDNDND231,2,3-三氯苯NDNDNDND241,2,4,5-四氯苯NDNDNDND251,2,3,4-四氯苯NDNDNDND26五氯苯NDNDNDND27六氯苯NDNDNDND