废弃等离子显示屏玻璃中重金属化学形态分布

通过BCR3步和BCR4步连续提取法,对等离子体显示屏玻璃中重金属的化学形态进行研究。结果表明,BCR3步连续提取法对废弃等离子体显示屏玻璃中重金属的提取比BCR4步连续提取法更稳定。废弃等离子体显示屏玻璃中Zn、Cu和Ag化学形态分布存在差异。BCR3步和BCR4步连续提取法均认为Ag以残渣态为主要赋存形态,对环境影响比较小;Cu的可交换与弱酸可溶态或交换态和碳酸盐结合态含量较少,潜在的环境风险也比较小;BCR3步和BCR4步连续提取法对Zn的形态分布结果评价不一致,BCR3步连续提取法表明Zn主要以可交换与弱酸可溶态为主,对环境影响较大,而BCR4步连续提取法结果认为Zn是以铁锰氧化态为主要存在形态。

Chemical form distribution characters of heavy metals in waste PDP glass

The chemical form of heavy metals from waste plasma display panel(PDP) glass was studied through BCR’s three stage(BCR3) extraction procedures and BCR’s four stage(BCR4) extraction procedures.The results show that the heavy metal extraction effect with BCR3 procedures was steadier than that with BCR4 procedures.There are significant differences in chemical form distributions of Zn,Cu and Ag in waste PDP glass.Both BCR3 and BCR4 think the chemical form of Ag in waste PDP glass exists mainly in residual forms and has little effect on the environment.The percentage of exchangeable and weak acid soluble form with BCR3 procedures or exchangeable metals and metals associated to carbonates form with BCR4 procedures of Cu are low,which has little risk for the environment.The estimates of the chemical form of Zn with BCR3 and BCR4 are inconformity,metals associated to oxides of Fe and Mn forms of Zn is the main form in waste PDP glass with BCR4 procedures,while the percentage of exchangeable and weak acid soluble form of Zn is the highest with BCR3 procedures,the harm of Zn from waste PDP glass is high.