典型煤矸石基分子筛修复镉污染土壤的生态风险  

Ecological risk of typical coal gangue-based molecular sieves in cadmium-contaminated soil remediation

作　　者：洪程 叶秋月 刘谦 皇甫卓曦 余江[2] HONG Cheng;YE Qiuyue;LIU Qian;HUANGFU Zhuoxi;YU Jiang(The 5th Geological Brigade of Sichuan,Chengdu 610036,Sichuan Province,P.R.China;College of Architecture and Environment,Sichuan University,Chengdu 610065,Sichuan Province,P.R.China;Sichuan Land Development Group Co.Ltd.,Chengdu 610031,Sichuan Province,P.R.China)

机构地区：[1]四川省第五地质大队,四川成都610036 [2]四川大学建筑与环境学院,四川成都610065 [3]四川省土地发展集团有限责任公司,四川成都610031

出　　处：《深圳大学学报(理工版)》2025年第2期138-145,I0002,共9页Journal of Shenzhen University(Science and Engineering)

基　　金：四川省地质局专项资助项目(SCDZ-DH202404)。

摘　　要：为探究典型煤矸石基分子筛作为稳定剂在修复受重金属镉(Cd)污染土壤中的应用,以高铁含量X型分子筛(Fe-NaX)与氨基改性X型煤矸石分子筛(NH_(2)-NaX)作为稳定剂,采用初始pH值为5.0的淋洗液模拟酸雨条件,通过柱状淋溶装置进行土壤中Cd的淋出实验,分析土壤中Cd的释放行为和迁移扩散规律.研究结果表明,在分别添加Fe-NaX型和NH_(2)-NaX型分子筛后,淋出液的pH值、电导率(electrical conductivity,EC)和Cd浓度均呈现出先快速上升,再缓慢下降并趋于稳定的现象;随着淋溶次数的增加,Cd累积淋出量初期迅速上升,后期缓慢上升总体呈现上升趋势.以Elovich Freundlich和Elovich修正方程、抛物线方程对Cd累积释放进行拟合,得到的相关系数R^(2)均大于0.98,表明拟合效果较好;相较于对照组,添加稳定剂后淋出液的可交换态Cd含量降低,部分转化为稳定的残渣态Cd,即Fe-NaX型和NH_(2)-NaX型分子筛均可有效抑制酸雨作用下土壤重金属Cd的淋溶,降低其生态环境风险.研究成果不仅揭示了典型煤矸石基分子筛作为稳定剂用于酸雨环境下污染土壤修复的潜在价值,还为其在重金属污染土壤治理中的广泛应用提供了科学依据.To investigate the application of using typical gangue-based molecular sieves as stabilizers for the remediation of soil contaminated with heavy metal cadmium(Cd),we used high iron content X-type molecular sieves(Fe-NaX)and amino-modified X-type gangue-based molecular sieves(NH_(2)-NaX)as stabilizers,and simulated the conditions of acid rain by using a leaching solution with an initial pH value of 5.0 conducted column leaching experiments on the soil containing heavy metal Cd to study the release behavior and migration/diffusion patterns of Cd in the soil.The results showed that after adding Fe-NaX and NH_(2)-NaX molecular sieves,the pH,electrical conductivity(EC)and Cd concentration in the leachate initially increased rapid,then slowly decreased and stabilized.As the number of leaching cycles increased,the cumulative amount of Cd leached generally exhibited an overall upward trend,characterized by a rapid increase in the initial phase,followed by a slower rise.The parabolic equation,Elovich modified equation and Freundlich modified equation were used to fit the cumulative release of Cd.The correlation coefficients(R^(2))for all these models were greater than 0.98,indicating a good fit.Compared with the control group,the exchangeable Cd content in the leachate decreased with addition of stabilizers as some Cd was converted into stable residual forms of Cd.This result indicates that both Fe-NaX and NH_(2)-NaX type molecular sieves can effectively inhibit the leaching of heavy metal Cd from soil under acid rain conditions,thereby reducing its ecological risk.This study not only reveals the potential value of typical gangue-based molecular sieves as stabilizers for remediation of contaminated soil under acid rain conditions,but also provides a scientific basis for their wide application in the treatment of heavy metal-contaminated soils.

关 键 词：修复材料 土壤修复 典型煤矸石基分子筛 镉污染 酸雨 生态风险 柱状淋溶 

分 类 号：TD849.5[矿业工程—煤矿开采] X53[矿业工程—矿山开采]