Rodriguez Alfonso, Lemos Daniela, Trujillo Yessika T, Amaya Julián G, Ramos Laura D
Universidad de la Sabana, Cundinamarca, Colombia.
Pure Earth, New York, NY.
J Health Pollut. 2019 Jul 23;9(23):190907. doi: 10.5696/2156-9614-9.23.190907. eCollection 2019 Sep.
Recent studies have explored the potential for using biochar as a soil amendment in agriculture. However, it can also be used as a gentle remediation option for contaminant reduction. Biochar is a by-product obtained from the pyrolysis of biomass (organic matter). It is known for its long-lasting chemical properties, wide surface area values, and carbon-richness, which make it an efficient method for the immobilization of organic and inorganic contaminants such as heavy metals.
The aim of the present study was to analyze the efficiency of biochar, obtained from the gasification of corncob, for the immobilization of lead in contaminated soils.
In the present study, biochar from corncob was used as an amendment for soil contaminated with lead (extracted from the municipality of Malambo, Colombia) in order to estimate its ability to immobilize leaching lead. A comparison laboratory test applied a modified biochar produced with a 10% hydrogen peroxide chemical treatment. In addition, a pot experiment was done with both biochar by sowing seeds of Pennisetum clandestinum for 33 days. During this period, plant growth was measured for the different amendments of biochar concentrations.
Laboratory tests indicated that unmodified biochar obtained a maximum retention of 61.46% of lead, while the modified biochar obtained only 44.53% retention. In the pot experiments, the modified biochar indicated high germination and growth of seeds (up to 89.8%).
Although the lead immobilization in soil was positive for both cases, the use of soil with high concentrations of lead (167.62 g/kg) does not indicate biochar's effectiveness for purposes of comparison with the current United States Environmental Protection Agency (USEPA) limit value (400 ppm for bare soil in urban play areas). Therefore, further studies are recommended using soil with lower lead concentration levels.
The authors declare no competing financial interests. One author is an employee of Pure Earth.
近期研究探索了将生物炭用作农业土壤改良剂的潜力。然而，它也可作为一种温和的修复选择以减少污染物。生物炭是生物质（有机物）热解产生的副产品。它以其持久的化学性质、较大的表面积值和富含碳而闻名，这使其成为固定有机和无机污染物（如重金属）的有效方法。
本研究的目的是分析由玉米芯气化得到的生物炭对污染土壤中铅的固定效率。
在本研究中，将玉米芯生物炭用作哥伦比亚马拉姆博市提取的铅污染土壤的改良剂，以评估其固定淋溶铅的能力。一项对比实验室试验使用了经10%过氧化氢化学处理产生的改性生物炭。此外，用这两种生物炭进行了盆栽试验，播种地毯草种子33天。在此期间，测量了不同生物炭浓度改良剂处理下的植物生长情况。
实验室试验表明，未改性生物炭对铅的最大保留率为61.46%，而改性生物炭的保留率仅为44.53%。在盆栽试验中，改性生物炭显示出种子的高发芽率和高生长率（高达89.8%）。
尽管两种情况下生物炭对土壤中铅的固定效果都是积极的，但使用铅浓度高（167.62 g/kg）的土壤并不能表明生物炭与美国环境保护局（USEPA）当前限值（城市游乐区裸土为400 ppm）相比的有效性。因此，建议使用铅浓度较低的土壤进行进一步研究。
作者声明不存在相互竞争的财务利益。一位作者是纯地球公司的员工。
