富里酸(FA)对微囊藻毒素-LR(MC-LR)的光降解作用及环境影响因素分析
Photodegradation of microcystin-LR(MC-LR)by fulvic acid(FA)and effect of environmental factors
汪艳昭 1张静静 1张达娟 1戴伟 1毕相东1
作者信息
- 1. 天津农学院水产学院,天津市水产生态及养殖重点实验室,天津 300384
- 折叠
摘要
为研究自然水环境中溶解性有机质(DOM)对微囊藻毒素-LR(MC-LR)的光降解作用,选择DOM的主要光敏活性组分富里酸(FA)作为光敏剂,在模拟太阳光照射下,对比了不同质量浓度FA(2.5、5.0、7.5、10.0 mg/L)溶液中MC-LR的光降解规律和光降解产物,并探究了不同pH、光照度对FA光降解MC-LR的影响.结果表明:MC-LR能在去离子水中发生直接光降解反应,不同质量浓度的FA对MC-LR的光降解均有促进作用,其中,7.5 mg/L FA对MC-LR的光降解作用最强,180 min时降解率达52.65％;FA对MC-LR的光降解过程符合二级反应动力学方程,其光降解产物与在去离子水中直接光降解的产物相同;不同pH和光照度下,FA对MC-LR的光降解作用依次为pH 6＞pH 7＞pH 8＞pH 9,39.8 μmol/(s·m2)＞56.9 μmol/(s·m2)＞22.8 μmol/(s·m2).研究表明,pH 和光照度均会影响 FA 对 MC-LR 的光降解作用,其中,pH为6、光照度为39.8 μmol/(s·m2)时,FA对MC-LR光降解作用最强.
Abstract
To investigate the photodegradation of microcystin-LR(MC-LR)by dissolved organic matter(DOM)in natural aquatic environments,the photolysis patterns and products of MC-LR in the main photosensitizer of DOM fulvic acid(FA)solutions with different concentrations of 2.5,5.0,7.5 and 10.0 mg/L were compared under simulated solar irradiation,and the effects of different pH values and light intensities on FA photodegradation of MC-LR were investigated.The results showed that the direct photolysis of MC-LR was found in deionized water.Different concentrations of FA led to promote the photolysis of MC-LR,with the best photodegradation at 7.5 mg/L of FA.There was degradation rate of 52.65％in 180 min.The photodegradation of MC-LR by FA was shown to be conformed to the second-order reaction kinetics,with the same photodegradation products as the direct photolysis products in deionized water.The descending order of photodegradation effects of FA on MC-LR were described as pH 6＞pH 7＞pH 8＞pH 9 and 39.8 μmol/(s·m2)＞56.9 μmol/(s·m2)＞22.8 μmol/(s·m2),indicating that both pH value and light intensity affected the photodegradation of FA on MC-LR.The best promoting effect of FA on the MC-LR photodegradation was observed at pH 6 and light intensity of 39.8 μmol/(s·m2).
关键词
富里酸/微囊藻毒素/光降解/溶解性有机质(DOM)Key words
fulvic acid(FA)/MC-LR/photodegradation/dissolved organic matter(DOM)引用本文复制引用
基金项目
国家自然科学基金面上项目(32172978)
天津市科技计划(22JCYBJC00430)
天津市科技计划(22ZYCGSN00050)
甘肃省科技计划(21CX6NP223)
天津市教委科研项目(2021KJ110)
出版年
2024
NETL
NSTL
维普
万方数据