静电纺丝制备复合纳米纤维及其在废水处理中的应用

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摘要

随着工业的迅速发展，环境污染已经日益受到社会和人们的重视。在环境治

理领域中，重金属及染料废水的治理一直是科研工作者研究的重点和热点，也是

社会广泛关注的焦点。六价铬容易被人体吸收并在体内积累，具有致癌并诱发基

因突变的危害。同时，多数染料及染料中间体都具有致癌、致畸及致突变效应，

而染料废水因具有水质复杂，色度高、毒性大、可生化降解性较差等特点，一直

是废水治理的难点，对生态环境和人类健康危害非常之大。因此，对重金属六价

铬及染料废水的治理的研究具有十分重要的意义。

纳米纤维具有独特和新颖的物理及化学特性，被广泛应用于环境治理等领域。

本研究以纳米纤维为基材，结合静电纺丝技术，制备具有大的比表面积、高孔隙

率及易表面修饰的复合纳米纤维材料，用于吸附处理六价铬和光催化降解染料废

水。采用高分子聚丙烯腈制备纺丝溶液，分别负载 Fe2+于纤维上，制备 Fe/PAN 复

合纳米纤维，既利用纳米纤维大的比表面积和高孔隙率又利用二价铁的还原特性，

吸附还原六价铬；负载铁及纳米二氧化钛于纤维上，制备 Fe-TiO2/PAN 复合纳米纤

维，对TiO2进行改性，有效扩展其对太阳光的利用效率，提高光催化氧化性能，

近可见光下光催化降解染料 RG19 和MG。

结论如下：

（1） Fe/PAN 复合纳米纤维

1、本研究通过溶胶凝胶法合成Fe/PAN 纺丝溶液，之后成功利用静电纺丝技术制

备了Fe/PAN 复合纳米纤维材料。纤维比表面积为13.8m2 g-1，并且具有较好的

热稳定性。纤维形态结构均匀，为纳米多孔结构，通过 XRD 分析表明此复合

纳米纤维具有无定形结构特征。

2、作为一种新型的铬离子吸附剂，充分利用了修饰 Fe2+的还原特性。纤维表面的

PAN…Fe(Π) (OH)+能与 Cr(Ⅵ)发生氧化还原反应，亚铁离子被氧化成Fe(Ⅲ)，而

Cr(Ⅵ)则被还原为 Cr(Ⅲ)，或形成 PAN…Fe1-xCrx(OH)x 的结构形式。既能提高

复合纳米纤维对铬离子的吸附能力又能将其还原为毒性低的Cr3+，减弱了铬的

毒性。

3、在研究不同实验参数对吸附处理效率的影响中，1.4%Fe 含量的复合纳米纤维对

铬离子的去除效率最高；研究发现，当处于 pH 为5的弱酸性环境下，复合纳

米纤维对铬离子的去除效果最为明显。

4、研究吸附等温线和反应动力学可以发现，Langmuir 模型和假二级动力学更适合

本研究实验。复合纳米纤维对铬离子的吸附为单分子层吸附模式，最大吸附量

上海理工大学硕士学位论文

为108mgCr/gFeCl2。

5、本研究利用瞬态动力学模型对铬离子吸附-脱附行为进行拟合，结果发现理论数

值与实验数据有很好的拟合度，证明本实验的可行性；根据热力学分析可以发

现，焓变值为-72.63KJ mol-1 即本研究实验为放热的化学反应过程；吉布斯自由

能值随着温度的升高由负变为正，说明反应由自发性趋向非自发性进行。

（2）Fe-TiO2/PAN 复合纳米纤维

1、本研究通过溶胶凝胶法合成Fe-TiO2/PAN 纺丝溶液，之后成功利用静电纺丝技

术制备了Fe-TiO2/PAN 复合纳米纤维。Fe-TiO2很好的分散和镶嵌在复合纳米纤

维表面，纤维直径大约100nm。并且具有很好的热稳定性和对可见光的吸收性

能。

2、在研究光催化降解两种不同性质染料酸性RG19 和碱性MG 的实验中，通过对

比不同实验参数对光催化降解的影响，发现RG19 在酸性条件下光催化效果更

好，而 MG 在碱性条件下处理效果更佳；1.4%Fe 含量的复合纳米纤维表现出

最高的染料降解效率。

3、研究不同pH 值条件下，同时混合处理两种染料，由于互相竞争影响，两种染

料的光催化效果都有明显降低。根据对电子-空穴对与自由基抑制剂添加的研究，

发现TBA 对两种染料的抑制作用要更显著，即本实验中自由基在光催化降解

染料中起到更重要的作用。

4、根据分析Julson-Ollis 模型可知，光降解染料经一步降解至中间产物，然后再被

分解为无色物质，Julson-Ollis 模型数据表明本研究实验值与理论值有很好的拟

合性及可行性。

关键词：静电纺丝聚丙烯腈铁二氧化钛复合纳米纤维铬染料

ABSTRACT

With the rapid development of industry, environment pollution has been

increasingly brought to the attention of the society and people. In the field of

environmental governance, heavy metals and dyes wastewater treatment has been the

focus and hotspot in the research of the scientific research worker. As is known to all,

hexavalent chromium easily absorbed and accumulated in the body, which has induced

gene mutations and cancer. At the same time, most of the dyes and dye intermediates

have carcinogenic, teratogenic and mutagenic effects, and because the dye wastewater

treatment has complex water quality, high chromaticity, high toxicity, poor biochemical

degradability, has always been the difficulty of wastewater treatment on the ecological

environment and human health hazard is very large. Therefore, for heavy metal

hexavalent chromium and dye wastewater management is imminent.

Nanometer fiber has a unique and novel physical and chemical properties, which

widely used in environmental governance, and other fields. This study is nanofibers as

base material, combined with the electrostatic spinning technology, preparation with

large specific surface area, porosity and surface modification of nanometer fiber

composite materials, which used to deal with the adsorption of hexavalent chromium

and light catalytic degradation of dye wastewater. Research in this paper, a polymer

preparation polyacrylonitrile spinning solution load Fe2+ on the fiber, the preparation of

Fe/PAN composite nanofibers, both using nanofibers large specific surface area and

porosity and using bivalent iron reduction properties, adsorption reduction hexavalent

chromium; Loaded with iron and nanometer titanium dioxide fiber, the preparation of

Fe-TiO2/PAN composite nanofibers, modification of TiO2 effectively extend its use

efficiency of sunlight, improving the performance of photocatalytic oxidation RG19 and

MG closing to the visible light.

And test conclusions are as follows:

（1）Fe/PAN composite nanofibers

1、Preparation of the composite nanofiber morphological structure and specific surface

area is about 13.8 m2 g-1 and the existence of the nanoporous structure. The success

of Fe2+ introduction can be obtained by FTIR characteristics analysis; The XRD

analysis, this study the preparation of composite nanofiber has the characteristics of

amorphous structure.

2、As a new type of chromium ion adsorbent, making full use of the modified reduction

上海理工大学硕士学位论文

characteristics of Fe2+. On the surface of the fiber PAN…Fe(Π) (OH)+ with Cr (Ⅵ)

reaction, ferrous ion is oxidized to Fe(Ⅲ), and Cr(Ⅵ) is reduced to Cr(Ⅲ), or form

the structure of PAN …Fe1-xCrx(OH)x. The composite fiber has excellent

performance of removing Cr6+, than the previous studies of the report has a faster

removal rate.

3、In the study the influence of different experimental parameters on the adsorption

process efficiency, 1.4% Fe content in the composite nanofibers of chromium ion

removal efficiency is highest; At the same time, the chromium removal efficiency

with the loss of the pollutant concentration and composite nanofibers dosing

quantity increases; And, the study found that when in weak acidic conditions, pH of

5 composite nanofibers on chromium ion removal effect is most obvious.

4、The adsorption isotherm and reaction kinetics can be found that Langmuir model and

fake secondary dynamics more comfortable. Composite nanofibers of chromium ion

adsorption for monolayer adsorption mode, maximum adsorption capacity for 108

mgCr/gFeCl2.

5、This study also used the transient dynamics model of chromium ion adsorption -

fitting behavior of stripping, found that the theory have good fitting, numerical and

experimental data prove the feasibility of the experiment; Thermodynamic analysis

can see, enthalpy change value is 72.63 KJ mol-1 in this study for exothermic

chemical adsorption experiments reaction process; The gibbs free energy values

with the increase of temperature from negative to positive, reaction by spontaneous

tendency in the spontaneous.

（2）Fe-TiO2/PAN composite nanofibers

1、SEM analysis suggested that Fe-TiO2 good dispersion and embedded in composite

nanofiber surface, fiber diameter of about 100 nm. And has good thermal stability

and to visible light absorption performance.

2、In the research of photocatalytic degradation of two dyes with different properties

experiments, RG19 acidic and alkaline MG. By comparing the influence of different

experimental parameters light catalytic degradation, found that under acid condition

RG19 photocatalytic effect is better, and MG in alkaline conditions better treatment

effect; 1.4% of Fe content in the composite nanofibers showed the highest dye

degradation efficiency; And photocatalytic degradation efficiency of the dye with

the loss of the pollutant concentration and composite nanofiber increased with the

ABSTRACT

increasing of the dosing quantity.

3、Research under the condition of different pH value, at the same time, mixed with two

kinds of dyes, because of the influence of competing with each other, photocatalytic

effect of two kinds of dyes are significantly reduced. According to the electronic -

hole with free radical inhibitor added research, found that associates to the

inhibitory effect of two kinds of dye is more significant, namely the experiment of

free radicals in the photocatalytic degradation of dye plays more important role.

4、From the model of Julson - Ollis, the light degradation of dye degradation by the step

to intermediate, and then was decomposed into colorless substance, Julson - Ollis

model data suggest that this study has a good fitting experimental value with the

theoretical and feasibility.

Key word：electrospinning, PAN, Fe, TiO2, composite nanofibers, Cr,

dye

中文摘要

ABSTRACT

第一章绪论 .................................................................................................................... 1

1.1 纳米材料 ........................................................................................................... 1

1.1.1 纳米材料简介 ........................................................................................ 1

1.1.2 纳米材料的特性 .................................................................................... 2

1.1.3 纳米纤维简介 ........................................................................................ 3

1.2 静电纺丝技术 ................................................................................................... 6

1.2.1 静电纺丝简介 ........................................................................................ 6

1.2.2 静电纺丝装置 ........................................................................................ 7

1.2.3 静电纺丝原理 ........................................................................................ 8

1.2.4 静电纺丝应用 ........................................................................................ 9

1.3 聚丙烯腈纳米纤维 .......................................................................................... 11

1.3.1 聚丙烯腈纳米纤维简介 ....................................................................... 11

1.3.2 聚丙烯腈纳米纤维的改性 .................................................................. 12

1.3.3 聚丙烯腈纳米纤维的应用 .................................................................. 12

1.4 研究意义、内容和实验方案 ......................................................................... 13

1.4.1 研究依据与意义 .................................................................................. 13

1.4.2 研究内容 .............................................................................................. 14

1.4.3 实验方案路线图 .................................................................................. 15

第二章实验内容 .......................................................................................................... 16

2.1 实验试剂及仪器 ............................................................................................. 16

2.1.1 主要实验试剂 ...................................................................................... 16

2.1.2 主要实验设备 ...................................................................................... 17

2.2 实验方法 ......................................................................................................... 18

2.2.1 Fe/PAN 复合纳米纤维的制备 ............................................................. 18

2.2.2 Fe-TiO2/PAN 复合纳米纤维的制备 .................................................... 19

2.3 材料表征分析 ................................................................................................. 20

2.4 污染物检测方法 ............................................................................................. 21

2.4.1 水中残留重金属 Cr(Ⅵ)的测定原理及方法 ...................................... 21

2.4.2 水中残余染料的测定原理及方法 ...................................................... 22

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摘要：

摘要摘要随着工业的迅速发展，环境污染已经日益受到社会和人们的重视。在环境治理领域中，重金属及染料废水的治理一直是科研工作者研究的重点和热点，也是社会广泛关注的焦点。六价铬容易被人体吸收并在体内积累，具有致癌并诱发基因突变的危害。同时，多数染料及染料中间体都具有致癌、致畸及致突变效应，而染料废水因具有水质复杂，色度高、毒性大、可生化降解性较差等特点，一直是废水治理的难点，对生态环境和人类健康危害非常之大。因此，对重金属六价铬及染料废水的治理的研究具有十分重要的意义。纳米纤维具有独特和新颖的物理及化学特性，被广泛应用于环境治理等领域。本研究以纳米纤维为基材，结合静电纺丝技术，制备具有大的比表面积、...

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