The Swiss Institute for Dryland Environmental and Energy Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Sde Boqer, 8499000, Israel.
Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Sde Boqer, 849900, Israel.
Chemosphere. 2019 Oct;232:130-139. doi: 10.1016/j.chemosphere.2019.05.093. Epub 2019 May 16.
Informal e-waste processing is a growing global problem. Local climate and mineralogical factors strongly control the chemical lability and dispersal of trace metals from informal e-waste processing. Previous work on e-waste contamination primarily focused on well-known sites in similar climates. Our exploratory analysis of a long-term (since 2008) e-waste incineration site in East Jerusalem demonstrated the ways in which local factors combined to uniquely control trace metal contaminant mobility. Our results suggest that the combination of e-waste processing methods, climate, and mineralogy at this site generated a geopolymer-like material combining ash from e-waste incineration and mountain rendzina soil. This material strongly sorbs trace metal contaminants. We measured the concentrations of: Cu, Fe, Mn, Pb, and Zn at 29 locations around and within the burn site. Samples collected less than 10 m from the edge of the incineration area had trace metal concentrations below the United States Environmental Protection Agency (U.S. E.P.A.) screening levels for residential soil. Sequential extraction showed that ∼50-80% of the total mobilized Pb was released from the residual solid fraction, suggesting strong sorption or incorporation into soil components. Large differences in the measured average specific surface areas (SSA) of uncontaminated (26.18 m/g) and contaminated (4.48 m/g) samples, despite comparable mineralogy by XRD, suggested the production of a geopolymer-like material. This was supported by close similarities between the SSA values of contaminated samples and those measured for geopolymer materials synthesized in the lab using kaolinite clay and fly ash (e.g., 4.9 m/g).
非正规电子废物处理是一个全球性的问题。当地的气候和矿物学因素强烈控制着从非正规电子废物处理中释放出来的痕量金属的化学活性和分散性。以前关于电子废物污染的研究主要集中在类似气候条件下的知名地点。我们对东耶路撒冷一个长期（自 2008 年以来）电子废物焚烧场的探索性分析表明，当地因素结合起来如何独特地控制痕量金属污染物的迁移。我们的研究结果表明，该地点的电子废物处理方法、气候和矿物学相结合，产生了一种类似于地质聚合物的材料，将电子废物焚烧的灰烬和山地岩土混合在一起。这种材料强烈吸附痕量金属污染物。我们在焚烧场周围和场内的 29 个地点测量了 Cu、Fe、Mn、Pb 和 Zn 的浓度。从焚烧区边缘采集的距离小于 10m 的样本的痕量金属浓度低于美国环保署（U.S. E.P.A.）对住宅土壤的筛选水平。连续提取表明，约 50-80%的总可移动 Pb 是从残余固体部分释放出来的，这表明存在强烈的吸附或与土壤成分结合。尽管 XRD 显示矿物学相似，但未受污染（26.18m/g）和受污染（4.48m/g）样本的测量平均比表面积（SSA）存在很大差异，这表明产生了一种类似于地质聚合物的材料。这得到了受污染样本的 SSA 值与使用高岭土粘土和粉煤灰在实验室合成的地质聚合物材料的 SSA 值（例如，4.9m/g）之间的密切相似性的支持。
