金属氧化物修饰活性炭微波催化降解染料废水

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摘要

研制了一种新型催化材料—载钴活性炭(ACCO)，并将其应用于吸附与微波催

化组合工艺处理染料废水。讨论了微波协同载钴活性炭降解染料废水的工艺路线；

筛选了处理工艺参数；研究了反应动力学；探讨了反应机理。

制备过程分为预处理、浸渍、焙烧三步。将经预处理的活性炭超声浸渍在硝

酸钴溶液中，焙烧滤出物，将含钴氧化物负载到活性炭上。通过单因素实验确定

了最佳制备条件：活性炭粒径为过 100 目筛；浸渍液为 0.017mol.L-1 硝酸钴溶液；

30℃下超声波频率为 59KHz，浸渍时间为 3小时；500℃下焙烧 3小时即得到载钴

活性炭。

采用热重分析、X-射线衍射、电镜扫描和碘吸附值测定对载钴活性炭结构进

行表征。载钴活性炭比活性炭的失重温度提高了 30℃，两者燃烧后的灰分差额证

实了负载物的存在。X-射线衍射表明载钴活性炭在



为20.9º、37.1º、43.0º时出现

吸收峰，掺杂的金属钴以氧化钴立方晶体形式存在于活性炭上。电镜扫描研究表

明氧化钴颗粒占据了活性炭部分孔隙，活性炭表面结晶缺陷增多，表面更加不均

匀。载钴活性炭的碘吸附值为 713 mg.g-1，低于经预处理活性炭的碘吸附值 732

mg.g-1。

通过正交实验、单因素实验确定了微波协同载钴活性炭催化降解模拟染料废

水的最佳条件。降解亚甲基蓝：pH 7.0，载钴活性炭用量 1.000g.L-1，染料初始浓

度400 mg.L-1，微波功率 480 W，时间 600 S；降解阳离子红 X-GRL：pH 10.0，载

钴活性炭用量 0.600g.L-1，染料初始浓度 500 mg.L-1，微波功率 480 W，时间 600 S；

降解酸性嫩黄 G：pH 3.0，载钴活性炭用量 1.000g.L-1，染料初始浓度 400 mg.L-1，

微波功率 480 W，时间 600 S。在上述条件下，亚甲基蓝水溶液的色度去除率达

87.95%，

CODCr 去除率达 78.31%；阳离子红 X-GRL 水溶液的色度去除率达 96.18%，

CODCr 去除率达 89.70%；酸性嫩黄 G水溶液的色度去除率达 95.04%，CODCr 去除

率达 88.38%。

微波协同载钴活性炭处理亚甲基蓝、阳离子红 X-GRL 和酸性嫩黄 G反应过程

可用一级反应动力学方程拟合。

探讨了微波协同载钴活性炭催化降解模拟染料废水的反应机理。载钴活性炭

以物理吸附将染料分子吸附到表面，微波作用下，载钴活性炭表面的缺陷瞬间成

为“热点”，并作为“敏化剂”将微波能传递给吸附到活性炭上的染料分子，染料

分子与 “热点”接触，被诱导发生化学反应，最终被降解为 CO2和H2O。

研究了载钴活性炭的再生和循环利用问题。用去离子水洗涤使用过的载钴活

性炭，100℃下烘至恒重，经过 5次重复使用后，对亚甲基蓝、阳离子红 X-GRL

和酸性嫩黄 G的降解率下降值小于 10%。

微波协同载钴活性炭催化降解染料废水技术中载钴活性炭同时起着吸附剂和

催化剂的作用。该方法反应时间短、能量利用率高，有望在染料废水治理领域得

到广泛的应用。

关键词：微波载钴活性炭染料动力学反应机理

III

ABSTRACT

Activated carbon supported cobalt oxide (ACCO), a novel catalytic materials, was

prepared through the modification of activated carbon. ACCO was applied in the

treatment of dyeing wastewater by the combined process of adsorption and microwave

radiation. In this paper, the process route of microwave-assisted ACCO was sudied, the

parameter on the dyes discolour rate was screened, and the reaction mechanism of

microwave-assisted ACCO was discussed.

The preparation process consist of activation, impregnation and calcination. ACCO

was synthesized by ultrasonic impregnation, the facters of the reaction condition were

studied , the optimum conditions of the preparation ACCO were as follows: particle size

of activated carbon is 100 mesh, impregnating solution is 0.017mol.L-1 cobalt nitrate

solution, impregnation temperature T 303.15 K, the ultrasonic frequency is 59KHz,

dipping time is 3 hours, calcination temperature T 773.15 K, calcination time is 3 hours.

ACCO was characterized by thermogravimetric analysis(TGA), X-ray diffraction,

electron microscope scanning and determination of iodine number. As determined by

thermogravimetric analysis(TGA), loss temperatures of ACCO and activated carbon

were 380℃and 410℃, respectively. X-ray diffraction and electron microscope

scanning of ACCO compared with activated carbon indicate that cobalt oxide was

loaded on the activated carbon by cubic form, which occupied some pores of activated

carbon. The surface crystal defect of ACCO was increased, surface was more uneven

than activated carbon. The iodine number of ACCO is 713 mg.g-1, and the activated

carbon is 732 mg.g-1.

Microwave-assisted ACCO degradation of simulative dyeing wastewater, the

conditions was stuided through orthogonal experiments and single factor experiments.

(1) For Methylene Blue: under the conditions which the pH was 7.0, the ACCO amount

was 1.000g.L-1, the concentration of methylene blue was 400 mg.L-1, the microwave

power was 480 W, the radiation time was 600S, the discoloration rate was 87.95% and

CODcr removal rate was 78.31%. (2) For Cationic Red X-GRL: under the conditions

which the pH was 10.0, the ACCO amount was 0.600g.L-1, the concentration of cationic

red X-GRL was 500 mg.L-1, the microwave power was 480 W, the radiation time was

600S, the discoloration rate was 96.18% and CODcr removal rate was 89.70%. (3) For

acid yellow G: under the conditions which the pH was 3.0, the ACCO amount was

1.000g.L-1, the concentration of cationic red X-GRL was 400 mg.L-1, the microwave

power was 480 W, the radiation time was 600S, the discoloration rate was 95.04% and

CODcr removal rate was 88.38%.

The reaction process of microwave-assisted ACCO degradation of simulative

dyeing wastewater met with first-order kinetics equation.

The reaction mechanism of microwave-assisted ACCO degradation of simulative

dyeing wastewater was discussed. Under microwave irradiation, ACCO can absorb heat,

and the crystal defect of surface rapid rise of temperature become "hot spots". First,

ACCO physically adsorbed the dyes to the surface, then passed the microwave energy

to the dye as a "sensitizer". When the dyes got in touch with the "hot spots" , chemical

reaction was occurred, and the dyes were degraded to CO2and H2O finally.

The regeneration of ACCO was studied in this paper. Distilled water was used to

elute the ACCO after it reacted, dryed to constant weight under 100℃. The catalyse

capacity decrease less than 10% when ACCO was used 5 times. The experiments show

that ACCO is a stable material and can be used after regenerated.

In the process of microwave-assisted ACCO degradation of simulative dyeing

wastewater, ACCO adsorbed the dyes and induced the degradation reaction as a catalyst.

This method is simple, fast reaction, high energy efficiency. Besides, ACCO can be

reused after regenerated. Therefore, ACCO has considerable propsect in the treatment of

dyeing wastewater.

Keywords: Microwave, Activated carbon supported cobalt oxide, dyes,

kinetics, reaction mechanism

中文摘要

ABSRTACT

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

§1.1 印染废水简介 ............................................... 1

§1.1.1 印染废水来源 .......................................... 1

§1.1.2 印染废水特点 .......................................... 1

§1.2 治理含染料废水方法 ......................................... 3

§1.2.1 物理法 ................................................ 3

§1.2.2 化学法 ................................................ 4

§1.2.3 生物法 ................................................ 5

§1.3 活性炭简介 ................................................. 5

§1.3.1 活性炭分类 ............................................ 6

§1.3.2 活性炭结构 ............................................ 6

§1.3.3 活性炭在印染废水中的应用 .............................. 8

§1.4 微波技术及其应用 ........................................... 9

§1.4.1 微波技术简介 .......................................... 9

§1.4.2 微波加热原理 .......................................... 9

§1.4.3 微波诱导催化技术 ..................................... 11

§1.4.4 微波技术在环境工程中的应用 ........................... 11

§1.5 本课题的研究目的、意义和主要内容 .......................... 14

§1.5.1 研究目的和意义 ....................................... 14

§1.5.2 研究内容 ............................................. 14

第二章实验部分 ..................................................... 15

§2.1 实验仪器与材料 ............................................ 15

§2.1.1 实验仪器与装置 ....................................... 15

§2.1.2 实验试剂 ............................................. 16

§2.1.3 处理对象 ............................................. 16

§2.1.4 主要试剂的配制 ....................................... 17

§2.2 实验方法 .................................................. 19

§2.2.1 载钴活性炭制备方法 ................................... 19

§2.2.2 微波协同载钴活性炭催化降解染料废水 ................... 19

§2.2.3 载钴活性炭再生与循环利用方法 ......................... 20

§2.3 分析测试方法 .............................................. 20

§2.3.1 热重分析 ............................................. 20

§2.3.2 X-射线衍射 ........................................... 20

§2.2.3 电镜扫描 ............................................. 20

§2.3.4 碘吸附值测定 ......................................... 20

§2.3.5 染料浓度测定 ......................................... 21

§2.3.6 CODCr 测定 .............................................23

§2.3.7 去除率计算 ........................................... 23

§2.3.8 反应动力学研究方法 ................................... 24

第三章实验结果与讨论 ............................................... 25

§3.1 活性炭负载金属氧化物的制备 ................................ 25

§3.1.1 活性炭粒径 ........................................... 25

§3.1.2 浸渍溶液 ............................................. 25

§3.1.3 浸渍溶液浓度 ......................................... 26

§3.1.4 浸渍时间 ............................................. 27

§3.1.5 小结 ................................................. 27

§3.2 载钴活性炭的结构表征 ...................................... 28

§3.2.1 热重分析 ............................................. 28

§3.2.2 X-射线衍射 ........................................... 28

§3.2.3 电镜扫描 ............................................. 29

§3.2.4 碘吸附值测定 ......................................... 30

§3.2.5 小结 ................................................. 30

§3.3 微波协同载钴活性炭催化降解模拟染料废水 .................... 30

§3.3.1 正交实验 ............................................. 30

§3.3.2 pH 的影响 ............................................ 31

§3.3.3 载钴活性炭用量的影响 ................................. 32

§3.3.4 初始浓度的影响 ....................................... 33

§3.3.5 微波功率的影响 ....................................... 34

§3.3.6 微波时间的影响 ....................................... 35

§3.3.7 CODCr 去除率 ...........................................36

§3.3.8 小结 ................................................. 36

§3.4 反应机理探讨 .............................................. 37

§3.4.1 工艺比较 ............................................. 37

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摘要：

I摘要研制了一种新型催化材料—载钴活性炭(ACCO)，并将其应用于吸附与微波催化组合工艺处理染料废水。讨论了微波协同载钴活性炭降解染料废水的工艺路线；筛选了处理工艺参数；研究了反应动力学；探讨了反应机理。制备过程分为预处理、浸渍、焙烧三步。将经预处理的活性炭超声浸渍在硝酸钴溶液中，焙烧滤出物，将含钴氧化物负载到活性炭上。通过单因素实验确定了最佳制备条件：活性炭粒径为过100目筛；浸渍液为0.017mol.L-1硝酸钴溶液；30℃下超声波频率为59KHz，浸渍时间为3小时；500℃下焙烧3小时即得到载钴活性炭。采用热重分析、X-射线衍射、电镜扫描和碘吸附值测定对载钴活性炭结构进行表征。载钴活性炭...

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