Adsorption and catalytic degradation of organic contaminants by biochar: Overlooked role of biochar's particle size
Adsorption and catalytic degradation of organic contaminants by biochar: Overlooked role of biochar's particle size
复制标题
生物炭对有机污染物的吸附和催化降解：生物炭粒径的被忽视的作用
DOI：
10.1016/j.jhazmat.2021.126928
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发表时间：
2021-08-24
影响因子：
13.6
通讯作者：
Li, Long
中科院分区：
文献类型：
--
作者：
Jin, Zilan;Xiao, Shuangjie;Li, Long
生物炭（BC）被认为是一种很有前途的去除有机污染物的吸附剂和/或催化剂。然而，BC的颗粒尺寸和其吸附/催化性能之间的关系在很大程度上是不清楚的。因此，我们研究了粒径对在300-900 ℃热解的BC在三氯乙烯（TCE）吸附和过硫酸盐（PS）活化磺胺二甲嘧啶（SMT）降解的性能的影响。结果表明，高温热解BC（BC 900）对三氯乙烯具有上级吸附能力，对PS活化降解SMT具有良好的催化活性。与150-250 μ m、75-150 μ m和原始BC 900相比，0-75 μ m的BC 900对三氯乙烯的吸附效率最高，提高了19.5- 62.3%。同样，通过BC 900/PS系统的SMT去除率也随着BC颗粒尺寸的减小而从24.2%增加到98.3%。然而，粉碎后的BC的催化活性并没有像预期的那样显著提高，表明生物炭的性质不仅受尺寸效应控制。表征结果表明，小粒径炭具有较大的比表面积、较多的微孔、较高的电导率、丰富的石墨结构域和表面氧化还原活性官能团，从而增强了炭的吸附和催化能力。
Biochar (BC) is considered as a promising adsorbent and/or catalyst for the removal of organic contaminants. However, the relationship between the particle size of BC and its adsorption/catalysis performance is largely unclear. We therefore investigated the influence of particle size on the performance of BC pyrolyzed at 300-900 degrees C in trichloroethylene (TCE) adsorption and persulfate (PS) activation for sulfamethazine (SMT) degradation. The results showed that high-temperature pyrolyzed BC (BC900) presented superior adsorption capacity for TCE and excellent catalytic activity for PS activation to degrade SMT. Compared to 150-250 mu m, 75-150 mu m and pristine BC900, 0-75 mu m BC900 showed the highest TCE adsorption efficiency, which increased by 19.5-62.3%. Similarly, SMT removal by BC900/PS systems also increased from 24.2% to 98.3% with decreasing BC particle size. However, the catalytic activity of BC after grinding was not significantly improved as expected, indicating the properties of biochar was not only controlled by size effect. Characterization measurements proved that small-sized BC tended to have larger specific surface area, more micropores, higher conductivity, rich graphitic domains and surface redox-active functional groups, thus resulting in an enhanced adsorption and catalytic ability of BC.