天然水、海水、饮用水、矿物水废水中汞、汞含量、水汞、水中汞、总汞、重金属检测方案(测汞仪)

MERCURY DETERMINATION IN NATURAL, SURFACE, SEA, DRINKING, BOTTLED, MINERAL, AND WASTE WATER BY CVAAS Lumex Method M 01-51-2012 ISO 12846-2012 INTRODUCTION Mercury determination in natural, drinking, and waste waters is one of the most popular analyses used for environment pollution and sanitary control. Background concentrations of mercury in natural water are within several ng/l. Maximum national permissible levels for mercury in water lie in the range of 0.16–6 µg/l. For example, the following limits for mercury in drinking water are set, µg/l: 0.5 – Japan, Russia; 1 – Argentina, Australia, Brazil, China, EC; 2 – US EPA, US FDA; 6 – WHO. MEASUREMENT METHOD The measurement method is based on standard procedures of digestion of mercury compounds in a water sample, reduction of mercury cations from decomposed sample with a tin chloride solution in the reaction vessel of RP-92 attachment (“cold vapor” technique) and further determination of atomic mercury using the method of atomic absorption with the RА-915М analyzer (using single-path and multi-path cells). Depending on the chemical composition of a sample, one of the following two methods of digestion should be used. Method А (permanganate digestion) is recommended for preparation of samples with a complex matrix. This method is used to analyze natural, potable, and waste water. Method B (bromide-bromate digestion) suggests softer digestion conditions and is used to prepare samples of natural water (including seawater), mineral, potable water (including bottled and packaged water), and purified waste water. The method of LUMEX Instruments allows one to determine both total mercury content and dissolved forms of mercury. Approximate time of sample preparation for analysis is 30 minutes for Method B and 2 hours for Method A. Limit of detection 0.5–2.5 ng/l depends on the purity of reagents. The measurement ranges of the mass concentration of total or dissolved mercury are 0.010–2000 µg/l (Method A); 0.010–50 µg/l (Method B). The time of mercury concentration measurement does not exceed 2 minutes. For water samples with relatively high mercury content (above 3 µg/l), an express method of direct pyrolysis (without any sample pre-treatment) can be provided with RA-915M analyzer coupled with PYRO-915+ attachment. Overall time of the analysis is 1–2 minutes. EQUIPMENT AND REAGENTS The following equipment and materials are used for analysis: Mercury analyzer RА-915М with RP-92 attachment; PC with Windows® ХР/Vista/7/8/10 and RAPID software; СRM of mercury. EXAMPLES OF ANALYSIS The accuracy of the method was proved by the results of inter-laboratory proficiency testing programs, provided by the independent testing laboratories. Year Water samples Measured value, µg/l Certified value, µg/l 2010 OK 13-10 1.90.5 2.040.04 2013 OK C3-13 5.220.70 5.60.1 2014 OK L4-14 0.5070.101 0.500.03 LUMEX Instruments specialists took part in the validation of the method ISO 12846-2012 Water quality – Determination of mercury – Method using atomic absorption spectrometry (AAS) with and without enrichment. The information in this leaflet is supplemental. To get more specific information on this method, please contact the developer of this method LUMEX INSTRUMENT Group. NORTH AMERICA E-mail: eaa@lumexinstruments.com www.lumexinstruments.com EUROPE E-mail: info@lumexanalytics.de www.lumexanalytics.de RUSSIA E-mail: sales@lumex.ru www.lumexinstruments.com CHINA E-mail: lumex@lumex.com.cn www.lumexcn.com 天然水、饮用水、和废水中汞含量的测定是环境污染和卫生控制的最广泛分析手段。天然水中的汞背景值大概在几纳克每立方米。水中允许最大汞含量的范围为0.16-6 µg/l.例如，饮用水中下列限度被设定，µg/l：0.5----日本，俄罗斯;1------阿根廷，澳大利亚，巴西，中国，欧盟；2------美国环保署，美国食品药品管理局；6------WHO该测定方法是以水样中汞化合物的消解为基础，用RP-92附件（冷蒸气法）的反应容器中的氯化亚锡溶液从分解的样品中回收汞离子，并使用该方法进一步测定原子汞。用原子吸收测汞仪RA- 915M分析汞的方法（使用单光程或者多光程）。根据样品的化学成分，应使用下列两种消解方法之一。方法A（高锰酸盐消解）推荐比较强烈的消化条件，用于制备具有复杂基质的样品。该方法用于分析天然、饮用和废水。方法B（溴酸溴化物消化）属于较软的消化条件，用于制备天然水（包括海水）、矿物、饮用水（包括瓶装水和包装水）和净化废水的样品。