Tufts University, Department of Chemistry, 200 Boston Ave, Medford, MA, 02155, United States.
Tufts University, Department of Civil and Environmental Engineering, 200 College Ave, Medford, MA, 02155, United States.
J Hazard Mater. 2018 May 5;349:153-159. doi: 10.1016/j.jhazmat.2018.01.041. Epub 2018 Feb 2.
A green chemistry solution is presented for the remediation of heavy hydrocarbon impacted soils. The two-phase recovery system relies on a plant-based biopolymer, which releases hydrocarbons from soil, and polystyrene foam beads, which recover them from solids and water. The efficiency of the process was demonstrated by comparisons with control experiments, where water, biopolymer, or beads alone yielded total petroleum hydrocarbon (TPH) reductions of 25%, 52%, and 58%, respectively, compared to 94% when 1.25 mL of 1% biopolymer and 15 mg beads per gram of soil were agitated for 30 min. Reductions in TPH content were substantial regardless of soil fraction, with removals of 97%, 91%, and 75% from sand, silt, and clay size fractions, respectively. Additionally, treatment efficiency was independent of carbon number, C to C, as demonstrated by reductions in both diesel fuel (C-C) and residual-range organics (C-C) of ∼90%. Compared to other published polymer- and surfactant-based treatment methods, this system requires less mobilizing agent, sorbent, and mixing time. The remediation process is both efficient and sustainable because the biopolymer is re-useable and sourced from renewable crops and polystyrene beads are obtained from recycled materials.
提出了一种绿色化学解决方案，用于修复受重烃污染的土壤。该两相回收系统依赖于一种基于植物的生物聚合物，它能从土壤中释放烃类，以及聚苯乙烯泡沫珠，它能从固体和水中回收烃类。通过与对照实验的比较，证明了该工艺的效率，在对照实验中，单独使用水、生物聚合物或珠粒分别使总石油烃（TPH）的去除率达到 25%、52%和 58%，而当每克土壤用 1.25ml1%的生物聚合物和 15mg 珠粒搅拌 30min 时，TPH 的去除率达到 94%。无论土壤的哪个部分，TPH 的含量都有显著的减少，砂、粉砂和粘土的去除率分别为 97%、91%和 75%。此外，处理效率与碳数无关，如柴油燃料（C-C）和残余有机物质（C-C）的去除率分别约为 90%，这都证明了这一点。与其他已发表的聚合物和表面活性剂处理方法相比，该系统需要更少的活化剂、吸附剂和混合时间。该修复过程高效且可持续，因为生物聚合物可重复使用，来源于可再生作物，而聚苯乙烯珠是由回收材料制成的。
