| 微生物和酶促老化对Mg改性生物炭表面性质的影响 |
| 摘要点击 1421 全文点击 213 投稿时间：2024-01-02 修订日期：2024-03-14 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 微生物分泌物 生物老化 酶促老化 重金属吸附 Mg改性生物炭 |
| 英文关键词 microbial secretion biologically aged enzymatic aging heavy metal adsorption Mg-modified biochar |
| 作者 | 单位 | E-mail | | 钱敏 | 昆明理工大学环境科学与工程学院, 云南省土壤固碳与污染控制重点实验室, 昆明 650500 | 2154766927@qq.com | | 吴宇茜 | 昆明理工大学环境科学与工程学院, 云南省土壤固碳与污染控制重点实验室, 昆明 650500 | | | 韩琳希 | 昆明理工大学环境科学与工程学院, 云南省土壤固碳与污染控制重点实验室, 昆明 650500 | | | 陈瑞芝 | 昆明理工大学环境科学与工程学院, 云南省土壤固碳与污染控制重点实验室, 昆明 650500 | | | 段文焱 | 昆明理工大学环境科学与工程学院, 云南省土壤固碳与污染控制重点实验室, 昆明 650500 | duanwenyan0405@qq.com | | 陈芳媛 | 昆明理工大学环境科学与工程学院, 云南省土壤固碳与污染控制重点实验室, 昆明 650500 | |
|
| 中文摘要 |
| Mg改性生物炭性质优异具有广泛的应用前景,但微生物介导的老化过程对生物炭的理化性质和功能的影响并不明确.因此分别采用微生物老化和酶促老化方法对MgCl2浸渍改性生物炭进行为期6个月的老化实验.结果表明,微生物老化后,持久性自由基信号较低的700 ℃ Mg改性生物炭,微生物分泌的生物膜会包裹在生物炭表面,提高Mg改性生物炭表面的含氧官能团,导致其对Pb2+的最大吸附量从55.31 mg·g-1提高至86.27 mg·g-1.而持久性自由基信号较高的500 ℃ Mg改性生物炭,会抑制微生物在生物炭表面的生长繁殖,导致Pb2+的最大吸附量与未老化改性生物炭差距不大.酶促老化过程对比Mg改性生物炭孔隙破坏严重,导致老化后Mg改性生物炭对Pb2+的吸附量下降到22.18 mg·g-1,显著低于未老化的改性生物炭.由此可见,经微生物老化的Mg改性生物炭吸附容量优于经酶促老化的Mg改性生物炭,主要是因为生物炭表面被微生物覆盖后,生物炭表面表现出的含氧官能团来自于微生物的胞外分泌物,促进了Pb2+的去除. |
| 英文摘要 |
| The excellent surface properties of Mg-modified biochar have highlighted a broad application prospect for soil heavy metal mitigation. However, the soil biotic aging process can have an impact on the physical and chemical properties of biochar as well as the heavy metal removal performance. Therefore, MgCl2-modified biochar was subjected to a six-month microbial and enzymatically aged test to explore the effects of different biotic aging processes on the physical and chemical properties. The Pb2+ adsorption performance of Mg-modified biochar that experienced different aging processes was compared using isothermal adsorption experiments. The results showed that after microbial aging, the Mg-modified biochar pyrolyzed at 700 ℃ displayed a low persistent free radical signal, with the biofilm secreted by microorganisms wrapped on the surface of the biochar, leading to the increase in the oxygen-containing functional groups on the biochar surface and the increase in the maximum adsorption capacity of Pb2+ from 55.31 mg·g-1 to 86.27 mg·g-1. In contrast, a higher free radical signal of 500 ℃ pyrolyzed biochar suggested that the free radical inhibited the growth and reproduction of microorganisms on the biochar surface, resulting in an insignificant enhancement in maximum adsorption capacity to Pb2+ compared to that with unmodified biochar. The pores of the Mg-modified biochar were severely damaged during the enzymatically aged process, resulting in a decrease in the adsorption capacity of Pb2+ to 22.18 mg·g-1, which was significantly lower than that of the unmodified biochar. Therefore, the adsorption capacity of microbially aged Mg-modified biochar is superior to that of enzymatically aged Mg-modified biochar, mainly because the oxygen-containing functional groups exhibited on the surface of the biochar covered by microorganisms come from the extracellular secretions of microorganisms, which promote the removal of Pb2+. |
|
|
|
