湿碱消解-等离子体发射光谱法测定海洋沉积物中的生物硅

Determination of Biogenic Opal in Marine Sediments by Inductively Coupled Plasma-Atomic Emission Spectrometry with Wet Alkaline Digestion

利用湿碱式化学提取技术和电感耦合等离子体发射光谱仪,优化样品碱式消解方法,确定仪器最佳工作条件,建立了测定海洋沉积物中不同含量级别生物硅的方法。结果表明,仪器检出限为0.724μmol/L,方法检出限为0.942μmol/L。用于测定硅酸盐-硅溶液成分分析国家一级标准物质(GBW08648和GBW 08649,标准值分别为50.0μmol/L和100.0μmol/L),测定值分别为(49.888±0.275)μmol/L、(99.578±0.651)μmol/L,相对标准偏差为0.443%、0.527%;对于不同生物硅含量级别海洋沉积物样品的平行、独立测量,其相对标准偏差<8.9%。方法快速、简便、准确,可满足古海洋学不同时空尺度气候和环境分析的应用。

A method for the determination of biogenic opal with a wide content range in marine sediments using inductively coupled plasma-atomic emission spectrometry （ICP-AES） with wet alkaline digestion was reported in this paper. The chemical pretreatment procedure and instrument operation parameters for biogenic opal analysis were optimized. The detection limits of the instrument and method for biogenic opal were 0.724 μmol/L and 0.942 /μmol/L respectively. The method has been verified by analyzing the National Standard Reference Materials （NSRMs） of GBW 08648 and GBW 08649 and the analytical results of biogenic opal in these two NSRMs were in agreement with the certified values with precision of 0.443% RSD and 0.527% RSD respectively. The method has also been applied to the determination of biogenic opal in marine sediments with precision of less than 8.9% RSD and provides a simple, accurate and efficient means for biogenic opal measurement in climate and environment investigation with various temporal and spatial scales in paleoceanography.