改进BCR法测定公路两旁表层土壤中铂钯铑的化学形态  

Determination of Chemical Species of Platinum,Palladium and Rhodium in Roadside Surface Soil with a Modified BCR Method

作　　者：王琳[1,2,3] 来新泽[1,2] 唐志中[1,2] 王冀艳[1,2] 张帆[1,2] 

机构地区：[1]河南省岩石矿物测试中心,河南郑州450012 [2]国土资源部贵金属分析与勘查技术重点实验室,河南郑州450012 [3]河南省地质调查院,河南郑州450001

出　　处：《岩矿测试》2012年第6期954-960,共7页Rock and Mineral Analysis

基　　金：河南省国土资源厅2009年度两权价款地质科研项目(2010-61-19)

摘　　要：铂、钯、铑是汽车催化转换器中的主要成分,在有效治理汽车尾气污染的同时,不断排放并在环境中累积增加,随着元素的迁移、转化及地下水的循环,可能成为一种新的环境污染问题。本文将改进的BCR顺序提取法应用于铂族元素形态分析,结合铂族元素的性质,将公路两旁表层土壤样品中Pt、Pd、Rh分为酸溶态、可还原态、可氧化态和残渣态四种形态。实验优化了原始的BCR浸取条件,利用电感耦合等离子体质谱法测定Pt、Pd、Rh的各形态。各形态的精密度、检出限满足地质矿产实验室测试质量管理规范的监控要求,各形态浸取量之和与样品各元素的总量之比(回收率)在95.3%～110.0%,说明方法具有较好的准确性和重现性。通过实际样品分析,公路两旁表层土壤样品中铂族元素非残渣态含量顺序为Pd(57.23%～58.03%)>Rh(22.64%～25.80%)>Pt(17.91～20.57%),研究认为铂族元素进入生物圈的几率是Pd>Rh>Pt。Pt, Pd and Rh as the main ingredients in automotive catalytic converters, effectively reduce automobile exhaust pollution, but continuously emit into the environment. The migration, conversion and circulation in groundwater of these elements potentially generate new environmental pollution problems. In this paper the improved BCR sequential extraction method was applied to the chemical species analysis of platinum group elements （PGEs）. Combined with the nature of the PGEs, the chemical species of Pt, Pd and Rh in roadside surface soil were divided into four fractions： acid soluble, reducible, oxidisable and residual. The original BCR leaching conditions were optimized and Inductively Coupled Plasma-Mass Spectrometry （ICP-MS） was used to measure various chemical species of Pt, Pd and Rh. The precisions and detection limits of all the chemical species all met the monitoring requirements of the testing quality management for geological laboratories （DZ/T 0130--2006）. All the recoveries were from 95. 3% to 110. 0% , which indicated the established method had good accuracy and reproducibility. The analysis results for actual samples of the surface soil samples on both sides of the road demonstrated the contents of PGEs in non-residual fraction were in order as Pd（57.23% -58.03% ） 〉 Rh（22.64% -25.80% ） 〉 Pt（17.91% - 20.57% ） and the probabilities for PGEs entering the biosphere were Pd 〉 Rh 〉 Pt.

关 键 词：公路表层土壤 铂 钯 铑 化学形态 改进BCR法 电感耦合等离子体质谱法 

分 类 号：S151.93[农业科学—土壤学] O614.826[农业科学—农业基础科学]