Medyńska-Juraszek Agnieszka, Ćwieląg-Piasecka Irmina, Jerzykiewicz Maria, Trynda Justyna
Institute of Soil Science and Environmental Protection, Wroclaw University of Environmental and Life Sciences, Grunwaldzka 53, 50-357 Wrocław, Poland.
Faculty of Chemistry, Wroclaw University, Joliot-Curie 14, 50-383 Wrocław, Poland.
Materials (Basel). 2020 May 28;13(11):2462. doi: 10.3390/ma13112462.
There is an urgent need to search for new sorbents of pollutants presently delivered to the environment. Recently biochar has received much attention as a low-cost, highly effective heavy metal adsorbent. Biochar has been identified as an efficient material for cobalt (Co) immobilization from waters; however, little is known about the role of Co immobilization in soil. Hence, in this study, a batch experiment and a long-term incubation experiment with biochar application to multi-contaminated soil with distinct properties (sand, loam) were conducted to provide a brief explanation of the potential mechanisms of Co (II) sorption on wheat straw biochar and to describe additional processes that modify material efficiency for metal sorption in soil. The soil treatments with 5% (v/w) wheat straw biochar proved to be efficient in reducing Co mobility and bioavailability. The mechanism of these processes could be related to direct and indirect effects of biochar incorporation into soil. The FT-IR analysis confirmed that hydroxyl and carboxyl groups present on the biochar surface played a dominant role in Co (II) surface complexation. The combined effect of pH, metal complexation capacity, and the presence of Fe and Mn oxides added to wheat straw biochar resulted in an effective reduction of soluble Co (II), showing high efficiency of this material for cobalt sorption in contaminated soils.
目前迫切需要寻找能够吸附进入环境中污染物的新型吸附剂。最近，生物炭作为一种低成本、高效的重金属吸附剂受到了广泛关注。生物炭已被确认为从水中固定钴（Co）的有效材料；然而，关于钴在土壤中的固定作用却知之甚少。因此，在本研究中，进行了一项批量实验和一项长期培养实验，将生物炭施用于具有不同性质（砂土、壤土）的多污染土壤中，以简要解释钴（II）在小麦秸秆生物炭上的吸附潜在机制，并描述改变土壤中金属吸附材料效率的其他过程。用5%（v/w）小麦秸秆生物炭进行土壤处理被证明在降低钴的迁移性和生物有效性方面是有效的。这些过程的机制可能与生物炭添加到土壤中的直接和间接影响有关。傅里叶变换红外光谱（FT-IR）分析证实，生物炭表面存在的羟基和羧基在钴（II）表面络合中起主导作用。pH值、金属络合能力以及添加到小麦秸秆生物炭中的铁和锰氧化物的共同作用导致可溶性钴（II）有效减少，表明这种材料在污染土壤中对钴的吸附具有高效性。
