雪冰样品离子色谱分析对样品瓶选择及前处理的要求

用离子色谱分析雪冰样品中痕量化学成分时,样品瓶的选择和前处理是确保实验结果的关键环节之一.痕量雪冰样品瓶在选择时需要注意两点:第一,瓶子的材质要根据所采样品的性状和所测组份的化学性质选取;测试常规的阴、阳离子,需选择易于运输和保存的聚乙烯(PE)、聚丙烯(PP)等材质的塑料采样瓶;测试有机酸时,为避免瓶子本身对样品的污染,通常选择玻璃瓶;第二,要确保所选样品瓶的密闭性,为保证雪冰内痕量化学成分的准确测定,不同材质的样品瓶应采取不同的清洗流程.塑料瓶首先用洗涤剂浸泡6～8h后刷洗,再用蒸馏水浸泡24h后充分冲洗,最后采用18.2MΩ的超纯水浸泡12h并冲洗至空白检测合格;玻璃瓶则需首先用洗涤剂浸泡6～8h后自来水冲洗干净,接着在1%～2%盐酸溶液或铬酸洗液中浸泡48h后充分冲洗,再用蒸馏水冲洗浸泡24h,充分冲洗,最后用18.2MΩ的超纯水浸泡12h并冲洗至空白检测合格.此外,在样品的采集与运输过程中,一定要预留空白,以检验样品瓶从运出实验室至返回实验室的整个过程中是否受到系统性污染,做好整个过程的质量控制工作.

The Selection and Pretreatment of Bottle as a Container for Snow and Ice Specimen for Ion Chromatography Analysis

Selection and pretreatment of the bottle as a container for snow and ice specimen is a critical step to get reliable data by ion chromatography analysis.There are two issues needed to be paid attention when collecting snow and ice specimens.First,material of the bottle must be selected based on the features of the specimen and the chemical properties of the tested components,for example,the PE or PP bottle should be selected if the major ions need to be analyzed;secondly,the tightness of the bottle must be ...