土壤学报2024，Vol.61Issue(2)：456-468,13.DOI:10.11766/trxb202206200329
腐殖酸和pH对典型轮胎磨损颗粒迁移行为的影响机制
Influencing Mechanisms of Humic Acid and pH on the Migration Behavior of Typical Tire Wear Particles
摘要
Abstract
[Objective]Tire wear particles(TWPs),as one of the important types of microplastics(MPs),have received a lot of attention from ecologists for their ecological risk in recent times.Usually,the environmental behavioral processes of particulate pollutants are important influencing factors of their ecological risk.However,the migration process and influencing mechanisms of TWPs in porous media such as soil have not been reported so far.[Method]In this paper,C-TWPs prepared by freezing crushing and R-TWPs(rolling friction)and S-TWPs(sliding friction)produced by road wear were selected as typical research objects,and quartz sand columns were used to simulate and study the migration behavior of TWPs in environmental porous media such as soil,and to investigate the effects of natural organic matter humic acid(HA)and different pH(4,7 and 10)environments on the migration behavior of the above three types of TWPs.[Result]The results showed that HA(50 mg·L-1)significantly enhanced the mobility of the three types of TWPs,and the migration behavior of TWPs was differently affected by different pH(4,7 and 10)environmental conditions in the presence of HA(50 mg·L-1),with the medium-alkaline environment(pH=7/10)being more favorable for the migration of TWPs.This was mainly due to an increase in the negative zeta potentials of the surfaces of TWPs and quartz sand particles in the presence of HA and/or the medium alkaline environment(simultaneously).Also,the dispersion of TWPs was improved for smaller particle size distribution while the electrostatic repulsion between TWPs and quartz sand particles was increased,which contributed to the migration of TWPs.It is worth noting that the migration of C-TWPs prepared by low-temperature crushing was stronger than that of R-TWPs and S-TWPs in the presence of HA and under different environmental pH conditions.This was mainly attributed to the fact that C-TWPs carried a larger negative charge,smaller isoelectric point and stronger hydrophobicity,and these properties also contributed to the adsorption of more HA,thus enhancing their electronegativity.Nevertheless,R-TWPs and S-TWPs had less electronegativity on the surface due to the adhesion of road minerals,metal salts or dust that reduced the magnitude of the mentioned properties.[Conclusion]These results reveal the variability of the geochemical transport behavior of different types of TWPs in nature and suggest the necessity of studying the source properties(discharge mode)to determine the inherent differences in environmental behaviors and ecological risks of microplastics of the same material.关键词
轮胎磨损颗粒/石英砂柱/腐殖酸/pH/穿透曲线Key words
Tire wear particles/Quartz sand column/Humic acid/pH/Penetration curve分类
资源环境引用本文复制引用
李昆,孔德跃,陈星月,彭永红,修小嘉,苏涵,潘旻宇..腐殖酸和pH对典型轮胎磨损颗粒迁移行为的影响机制[J].土壤学报,2024,61(2):456-468,13.基金项目
江苏省自然科学基金项目(BK20210654)、南京信息工程大学科研启动经费资助项目(2021r049)和上海同济高廷耀环保科技发展基金项目(STGEF)共同资助 Supported by the Natural Science Foundation of Jiangsu Province,China(No.BK20210654),the Scientific Research Start-up Foundation of Nanjing University of Information Science and Technology,China(No.2021r049)and the Gaotingyao Environmental Protection Science and Technology Development Fund Project of Shanghai Tongji University,China(No.STGEF) （BK20210654）
