Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043, Cassino, Italy.
Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Via Di Biasio 43, 03043, Cassino, Italy.
Chemosphere. 2021 Jan;263:128274. doi: 10.1016/j.chemosphere.2020.128274. Epub 2020 Sep 7.
The contamination of sediments by polycyclic aromatic hydrocarbons (PAHs) has been widely spread for years due to human activities, imposing the research and development of effective remediation technologies for achieving efficient treatment and reuse of sediments. In this context, the amendment of biochar in PAH-contaminated sediments has been lately proposed as an innovative and sustainable technology. This review provides detailed information about the mechanisms and impacts associated with the supplementation of biochar to sediments polluted by PAHs. The properties of biochar employed in these applications have been thoroughly examined. Sorption onto biochar is the main mechanism involved in PAH removal from sediments. Sorption efficiency can be significantly improved even in the presence of a low remediation time (i.e. 30 d) when a multi-PAH system is used and biochar is provided with a high dosage (i.e. by 5% in a mass ratio with the sediment) and a specific surface area of approximately 360 m g. The use of biochar results in a decrease (i.e. up to 20%) of the PAH degradation during bioaugmentation and phytoremediation of sediments, as a consequence of the reduction of PAH bioavailability and an increase of water and nutrient retention. In contrast, PAH degradation has been reported to increase up to 54% when nitrate is used as electron acceptor in low-temperature biochar-amended sediments. Finally, biochar is effective in co-application with Fe for the persulfate degradation of PAHs (i.e. up to 80%), mainly when a high catalyst dose and an acidic pH are used.
多年来，由于人类活动，多环芳烃（PAHs）污染沉积物的情况已经广泛存在，这促使人们研究和开发有效的修复技术，以实现沉积物的有效处理和再利用。在此背景下，最近提出了在 PAH 污染沉积物中添加生物炭作为一种创新和可持续的技术。本综述详细介绍了与将生物炭添加到受 PAH 污染的沉积物相关的机制和影响。对这些应用中使用的生物炭的性质进行了彻底的检查。吸附到生物炭上是从沉积物中去除 PAHs 的主要机制。即使在使用多 PAH 系统且生物炭的剂量（即与沉积物的质量比为 5%）和比表面积（约 360 m g）较高的情况下，修复时间（即 30 天）较短，吸附效率也可以显著提高。使用生物炭会导致沉积物的生物修复和植物修复过程中 PAH 降解减少（即减少 20%），这是由于 PAH 的生物可利用性降低和水和养分的保留增加所致。相比之下，当在低温生物炭添加沉积物中使用硝酸盐作为电子受体时，据报道 PAH 的降解增加了 54%。最后，生物炭与 Fe 联合应用可有效用于过硫酸盐降解 PAHs（即高达 80%），主要是在使用高催化剂剂量和酸性 pH 值的情况下。
