石脑油、轻质油中汞、液体汞检测方案(测汞仪)

DETERMINATION OF THE MERCURY CONCENTRATION IN NAPHTHA COMPLIANT WITH ASTM D7622-10(2015) AND UOP-938-10 METHODS INTRODUCTION The mercury concentration in crude oil and petroleum products can vary in a wide range of less than 0.1 ppb to dozens ppm. Direct mercury determination in crude oil and petroleum products at the range above 5 ppb is covered by ASTM D7622-10(2015) "Standard test method for total mercury in crude oil using combustion and direct cold vapor atomic absorption method with Zeeman background correction". Mercury determination in naphtha and light petroleum products (condensate, gasoline and diesel fuel) at a level below 5 ppb is a vital problem for the oil refining and petrochemical industry. Complex organic matrix impedes conventional quantitative analysis for mercury. MEASURING METHOD The proposed method of direct mercury determination in naphtha, condensate, and light oil products is based on the atomization of mercury contained in the sample in a PYRO-915+ attachment and subsequent mercury determination by flameless AAS with a mercury analyzer RA-915M. At the mercury concentration above 1–5 ppb (g/kg), the analysis is made directly without any sample preparation and mercury accumulation on a sorbent. The sample of 50–200 µl is sufficient for mercury determination in a range of 5 ppb to 100 ppm. The analysis takes 1–2 min. If the mercury concentration is below 1–5 ppb, a preconcentration step is required. Mercury is extracted to a special solid sorbent from a sample of 1–5 ml that reduces the limit of detection down to 0.02 ppb. The analysis takes 5–6 min. ANALYSIS FEATURES Simple measurement procedure and user-friendly interface No sample preparation is necessary in the case of mercury concentration above 1–5 ppb. Preconcentration from a 1–5 ml sample is required for mercury determination at a sub-ppb level. Very fast analysis taking from 1 to 5 min. Wide dynamic measurement range, no "memory effect". The SRM of any composition can be used for calibration and validation of composition. The calibration coefficient has long-term (months).stability Control of the non-selective absorption during the measurement process excludes analysis errors. Visualization of the mercury release from the sample via a user-friendly computer interface. No need for cylinders with compressed oxygen or other carrier gas. Low running cost. ANALYTICAL CHARACTERISTICS Direct Analysis Preconcentration Sample composition crude oil, condensate, naphtha, gasoline, diesel fuel, lubricants, etc. condensate, naphtha, gasoline, diesel fuel Sample volume 20–200 l 1–5 ml Detection limit 1–5 ppb 0.02 ppb Upper limit of the measurement range 100,000 ppb 100 ppb Measurement time 1–2 min 5–6 min EQUIPMENT AND REAGENTS The following equipment and materials are used for analysis: Mercury analyzer RA-915M or RA-915+ with PYRO-915+ attachment; PC with Windows® ХР/Vista/7/8 and RAPID software; Any certified SRM of mercury; Set for mercury preconcentration. EXAMPLES OF ANALYSIS ( Sample weight, mg С, ppb 1 2537 0.70 2 2679 0.77 3 1447 0.72 4 3906 0.74 5 1855 0.79 6 2137 0.78 7 3106 0.72 8 3034 0.70 9 1743 0.68 10 3717 0.70 Сav, ppb 0.730 SD 0.037 RSD, % 5.1 )Measuring mercury concentration in naphtha using the preconcentration step. – sample weight 1.45 g; (measured value is 0.72 g/kg) – sample weight 3.03 g; (measured value is 0.70 g/kg) 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 Lumex Instruments Canada 0890278 B.C. Ltd. E-mail: info@lumexinstruments.com www.lumexinstruments.com EUROPE Lumex Analytics GmbH E-mail: info@lumexanalytics.de www.lumexanalytics.de RUSSIA Lumex-Marketing LLC E-mail: sales@lumex.ru www.lumexinstruments.com CHINA Beijing Lumex Analytical Equipment Co. Ltd. E-mail: lumex@lumex.com.cn www.lumexcn.com 2 石脑油和成品油中的汞含量范围很宽，小到0.1ppb，大到几十个ppm。目前可以用ASTM D7622-10（2015）、燃烧法和塞曼扣背景的冷原子吸收法测定原油中总汞的标准试验方法，在5 ppb以上范围内测定原油和石油产品中的汞。而对于5 ppb以下的石脑油和轻质石油产品（凝析油、汽油和柴油）中汞的测定是炼油和石化工业的一个重要问题。复杂的有机基质阻碍了汞的常规定量分析。 在汞浓度在1-5 ppb（g/kg）以上时，不需要任何样品制备和汞在吸附剂上的富集，可以直接进行分析。50-200μL的样品足可以在5 ppb到100 ppm的范围内进行准确测定，分析过程仅需要1-2分钟。 zài在 gǒng汞 nóng浓 dù度 zài在 1 ～ 5 p p b （ g g / k g ） yǐ以 shàng上 shí时 ， bù不 xū需 yào要 rèn任 hé何 yàng样 pǐn品 zhì制 bèi备 hé和 gǒng汞 zài在 xī吸 fù附 jì剂 shàng上 de的 jī积 lěi累 ， zhí直 jiē接 jìn进 xíng行 fēn分 xī析 。 5 0 — 2 0 0 μ L de的 yàng样 pǐn品 zú足 yǐ以 zài在 5 p p b dào到 1 0 0 p p m de的 fàn范 wéi围 nèi内 cè测 dìng定 gǒng汞 。 fēn分 xī析 xū需 yào要 1 dào到 2 fēn分 zhōng钟 。 If the mercury concentration is below 1–5 ppb, a preconcentration step is required. Mercury is extracted to a special solid sorbent from a sample of 1–5 ml that reduces the limit of detection down to 0.02 ppb. The analysis takes 5–6 min.如果汞浓度低于1 - 5 ppb，则需要预浓缩步骤。从1-5mL的样品中用一种特殊的固体吸附剂对汞进行富集，可以将检测限降至0.02 ppb，分析过程仅需要5-6分钟。