硫化亚铁矿活化产生硫酸根及羟基自由基氧化降解对氯苯胺
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摘要
对氯苯胺（PCA）是比较典型的苯胺类化合物，毒性大，化学稳定性和热稳
定性高，不易被直接分解或生物降解，严重威胁生态环境和人体健康。高效经济
地去除环境中氯苯胺类化合物是目前迫切需要解决的难题。过硫酸盐（persulfate，
PS)稳定性好且受 pH 影响小，具有较高的氧化还原电位，能活化产生强氧化能力
的硫酸根自由基（SO4-•），且氧化剂利用率较高，因此成为目前最具潜力的氧化剂。
常见活化 S2O82-产生 SO 4-•方法包括热，紫外光等物理方法和过渡金属离子如
Fe2+, Mn2+, Ag+, Cu2+, Co2+等化学方法。然而，高的能量消耗、窄的 pH 值使用范围
且氧化剂利用率低导致 S2O82—高级氧化技术在实际工程应用中受到一定的限制。
多相类 Fenton 反应能有效地解决了传统 Fenton 反应存在的催化剂难以回收利
用、溶液需要酸化及大量污泥产生等问题成为一个新的研究方向。然而现有的铁
基活化剂（Fe0，FexOy）在反应过程中产生大量的 Fe3+无法转化成 Fe2+而抑制反应
的循环进行，氧化效果不佳。本文探讨了硫化亚铁矿（FeS）作为铁源活化 S2O82-
和H2O2的特性,降解 PCA 的机制，以及 FeS 矿利用效率。主要研究内容如下：
（1）在 FeS 矿-PS 体系中，考察了溶液的初始 pH 值，S2O82-初始浓度，FeS
矿物投加量，无机阴离子（H2PO4-，HCO3-, Cl-, NO3-, SO42-）等因素对 PCA 降解效
率的影响。同时检测了反应过程中产生的中间离子 Fe3+、SO42-、Cl-和TOC, 并采
用间接法（甲醇和叔丁醇抑制剂）和直接法（ESR）检测了硫酸根和羟基自由基的
生成，初步探讨了 FeS 矿活化过硫酸盐产生硫酸根和羟基自由基的机制及其降解
PCA 的反应机理。研究结果表明：在 FeS-PS 体系中，FeS 矿能持续不断地提供 Fe2+
源，实现 Fe3+向Fe2+的转化，从而避免 Fe3+产生络合沉淀反应和 Fe2+的消耗。在实
验pH 范围内（pH3~11）， 对氯苯胺的降解效率均较高，但弱酸性（pH5）和中性
（pH7）条件下 PCA 的降解速率大于碱性和强酸性条件。随着 S2O82-和FeS 矿投
加量的增加，PCA 降解率逐渐增大，达到一定程度后趋于平衡。在最优条件下，
PCA 去除率高达 100%且能达到完全脱氯和矿化的效果。PCA 的脱氯和矿化降解
主要归因于 SO4-•和•OH 的高级氧化作用。
（2）在 FeS 矿- H2O2非均相类 Fenton 体系中，探讨了 pH、H2O2投加量、FeS
矿物投加量对类 Fenton 氧化 PCA 过程的影响, 确定了最佳反应条件。通过检测反
应过程中产生的 TOC，中间离子 Fe3+，SO42-,Cl-，初步分析了降解机理。研究结果
表明: FeS 矿对催化 H2O2氧化具有很强的催化活性，能提高 H2O2的利用效率。当
PCA 浓度为 0.2mM，溶液初始 pH 值为 3.0，H2O2投加量 0.8mM，FeS 矿用量为
0.4 g/L，反应 20min 时，PCA 去除率可达 100%，且反应进行到 40min 后，已达
到完全脱氯效果。
本研究着眼于研究常温常压下活化 S2O82-与H2O2 产生硫酸根和羟基自由基新
型高级氧化工艺，以 FeS 矿为活化剂，揭示了两种体系高效去除氯苯胺类化合物
的机制，探讨了工艺条件的优化，为废水处理提供了一条新途径。
关键词：硫化亚铁矿 高级氧化技术 过硫酸钠 双氧水 硫酸根自由基
对氯苯胺
ABSTRACT
P-chloroaniline (PCA) with high chemical sand thermal stability is typical
chlorophenols and recalcitrant organic pollutants which cannot be directly degradated
by conventional biological technologies. Moreover, it is harm to ecological environment
and human health. Therefore, it is an urgent problem to remove chloroaniline
compounds efficiently. Persulfate (S2O82-，abbreved as PS) is one of the strongest
oxidants in the aqueous solution. There exist many advantages including stablity at
room temperature, high oxidation-reduction potential to generate SO4•－, simple
operation and mild reaction conditions, which broaden its application in the degradation
and mineralization of the pollutants. PS is activated usually by uv light, heat and
transition metal ions, such as Fe2+, Mn2+, Ag+, Cu2+, and Co2+. However, disadvatanges
of high energy consumption，narrow pH value ranges and low utilization efficiency of
PS hinder its widely application. Fenton-like reaction catalyzed by iron-based materials
(Fe0, FexOy) with good separation and reutilization performance, as well as a wide pH
values ranges, has been intensively investigated as one of the most promising
developments in the field of advanced oxidation processes over the past years. But the
large amounts of Fe3+ were generated and the conversion to Fe2+ was inhibited, which
led to thethe reduced oxidation effect Therefore, the goals of the present work are to
explore the characteristics of persulfate and hydrogen peroxide activated by ferrous
sulfide ore particle，organic contaminants degradation performance and ultilization
efficiency of FeS The main studies are as followed:
(1) In FeS-PS system ，the effects of initial solution pH, FeS dose, PS concentration，
and various inorganie anion(H2PO4-，HCO3-, Cl-, NO3-, SO42-) on PCA degradation were
examined at 20±5 ºC in batch experiments. Cl-, SO42-, Fe3+ ions and TOC as the main
inorganic products were used to investigate the oxidative mechanism in the present
system. The sulfate and hydroxyl radicals in the FeS/PS system were confirmed by the
addition of tert-butyl alcohol ashydroxyl radical and sulfate radical scavengers. The
results showed that FeS could serve as a continuous -releasing source of dissolved Fe2+
and surface bound Fe2+ compared with Fe2+. In contrast with Fe0/PS system, recycling
of Fe3+ to Fe2+ can prevent excessive Fe2+ consumption and Fe3+ accumulation in the
FeS/PS system. The PS activation mechanism was affected by the initial solution pH.
And the application ranges of pH for PCA fast degradation was from 3.0 to 7.0 in the
tested pH values of 3.0~11.0. Especially good performance occurred in pHs of 5 and 7.
PCA degradation increased as the FeS dose and persulfate concentration increased. PCA
removal, dechlorination, and TOC removal reached over 99% within 60, 210, and 500
min, respectively. The dechlorination and mineralization of PCA can be attributed to
SO4-• and•OH advanced oxidation.
(2) Fenton-like reactions using FeS ore particles as heterogeneous catalysts for the
degradation of p-chloroaniline (PCA) was investigated through batch experiments.
Effects of initial pH, activator and H2O2 dosages on PCA degradation were examined to
determinethe optimum reaction conditions. Cl-, SO42- and Fe3+ ions as the main
inorganic products together with TOC in aqueous solution were determined to
investigate the oxidative mechanism. The results indicated that unlike traditional Fenton
reagent, the FeS ore particles could effectively catalyze the decomposition of H2O2 for
the oxidation of organic contaminants. Under the conditions with initial PCA
concentration of 0.2 mM, initial pH of 3.0, FeS ore particles dosage of 0.4 g/L, H2O2
concentration of 0.8 mM, PCA degradation in aqueous solution reached 100% within 20
min and dechlorination reached over 99% within 40 min.
This paper focused on researching and developing the novel AOPs which refers to
the generation of sulfate radicals and hydroxyl radicals via S2O82-and H2O2 reaction in
normal temperature and pressure. It discussed the formation mechanism of reactive
oxygen species, the degradation mechanism of chloroaniline and the optimization of
process conditions. The present study can provide a new way for wastewater treatment.
Key Words: ferrous sulfide ore particle (FeS), advanced oxidation
processess (AOPs), persulfate, hydrogen peroxide, sulfate radicals,
p-chloroaniline (PCA)
目录
摘要
ABSTRACT
第一章 绪论 ................................................................................................................. 1
1.1 对氯苯胺废水的危害及治理 .......................................................................... 1
1.2 高级氧化技术 .................................................................................................. 1
1.3 基于羟基自由基的高级氧化技术 .................................................................. 2
1.3.1Fenton 氧化法 ......................................................................................... 2
1.3.2 类 Fenton 氧化法 .................................................................................. 3
1.3.3 电化学氧化法 ........................................................................................ 5
1.3.4 光催化氧化法 ....................................................................................... 6
1.3.5 超声氧化法 ............................................................................................ 7
1.4 基于硫酸自由基的高级氧化技术 .................................................................. 7
1.4.1 SO4-•的产生机理 ................................................................................... 8
1.4.2 SO4-•与有机物反应机理 ..................................................................... 10
1.4.3 基于过硫酸盐高级氧化技术对废水中有机污染物的降解的应用 .. 11
1.5 研究目的、意义及研究内容 ........................................................................ 11
1.5.1 研究目的 .............................................................................................. 11
1.5.2 研究意义 .............................................................................................. 12
1.5.3 研究内容 .............................................................................................. 12
第二章实验材料与方法 ............................................................................................. 14
2.1 主要试剂与仪器 ............................................................................................ 14
2.1.1 主要试剂及其配制 .............................................................................. 14
2.1.2 主要仪器 .............................................................................................. 15
2.2 分析方法 ........................................................................................................ 15
第三章 硫化亚铁矿活化过硫酸钠降解对氯苯胺 ................................................... 18
3.1 引言 ................................................................................................................ 18
3.2 FeS 矿粉的表征 ............................................................................................. 18
3.3 FeS 矿催化效果与 Fe2+ 和Fe0 的比较 ...................................................... 20
3.4 溶液初始 pH 值对 PCA 降解率的影响 ....................................................... 22
3.5 FeS 矿投加量对 PCA 降解率的影响 ........................................................... 24
3.6 过硫酸钠浓度对 PCA 降解率的影响 .......................................................... 25
3.7 底物研究以及重复利用实验 ........................................................................ 27
3.8 反应体系中无机阴离子的生成和矿化作用 ................................................ 29
3.9 硫酸根、羟基自由基的检测 ........................................................................ 31
3.9.1 自由基清除剂对 PCA 降解效果的影响 ............................................ 31
3.9.2 自由基的 ESR 检测 ............................................................................. 34
3.10 在FeS 矿/PS 体系中可能存在的氧化机理 ............................................... 37
3.11 水中常见阴离子对苯胺降解的影响 .......................................................... 38
3.12 小结 ............................................................................................................. 39
第四章 硫化亚铁矿活化双氧水降解对氯苯胺 ....................................................... 41
4.1 引言 ................................................................................................................ 41
4.2 初始 pH 值对 PCA 氧化降解的影响 .......................................................... 41
4.3 FeS 矿投加量对 PCA 降解的影响 ............................................................... 42
4.4 双氧水投加量对 PCA 降解的影响 .............................................................. 43
4.5 PCA 的降解历程 ........................................................................................... 44
4.6 小结 ................................................................................................................ 46
第五章 结论与展望 ................................................................................................... 48
5.1 结论 ................................................................................................................ 48
5.2 展望 ................................................................................................................ 49
参考文献 ..................................................................................................................... 50
在读期间公开发表的论文和承担科研项目及取得成果 ......................................... 58
致谢 ............................................................................................................................. 58
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作者：侯斌
分类：高等教育资料
价格：15积分
属性：63 页
大小：4.75MB
格式：PDF
时间：2025-01-09
