季铵型阳离子纤维素对污染物吸附性能研究

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摘要

纤维素是地球上最丰富的可再生资源，具有价廉、可降解和对生态环境不产

生污染等优点，在解决人类所面临的能源、资源和环境问题方面具有重要意义。

但天然纤维素的吸附能力并不强，必须经过物理化学改性才能成为性能良好的吸

附材料，所以纤维素的功能化一直是人们研究的热点。

本论文合成了一种吸附水溶性有机污染物的新型环境友好材料—季铵型阳

离子纤维素（QACC），研究了其吸附性能、应用性能、吸附机理及其解吸再生性

能。棉纤维素碱化后，以异丙醇为分散剂，以 3-氯-2-羟丙基三甲基氯化铵（CHPT）

为醚化剂，在 75℃下反应 4h 制得 QACC，测得其含氮量为 1.71％。

本论文应用正交实验研究了吸附工艺参数对 QACC 吸附容量的影响，QACC

的最佳吸附参数为：吸附温度为 45℃，吸附 pH 值为近中性，振荡频率为 120r/min，

振荡时间为 60min。

季铵型阳离子纤维素可应用于吸附环境水体中的水溶性有机污染物，这些污

染物一般带有磺酸基、羧基、羟基和氨基等亲水基团，这些基团在水中离解后形

成路易斯碱。QACC 对路易斯碱的吸附主要由阳离子与路易斯碱基形成化学键完

成的，这种吸附具有吸附较牢固、吸附速度快、污染物去除率高等特点。

在45℃的近中性水溶液中，QACC 对含羧基、磺酸基、羟基、氨基的水溶性

有机污染物具有较大的饱和吸附容量。QACC 对所测试污染物的饱和吸附量分别

为：486mg 直接湖兰 5B/g、474mg 酸性红 B/g、431mg 酸性嫩黄 G/g、22mg 苯酚

/g、33.2mg 甲萘酚/g、3.22mg 苯胺/g、23.5mg 对氨基苯磺酸/g、24.4mg 2,3 酸/g、

37.7mg R 盐/g、52.8mg2-萘磺酸/g、33.6mg1-萘甲酸/g 和168 mg 十二烷基苯磺酸

酸钠/g。

动态穿透曲线表明，对于不同种染料，QACC 的动态吸附容量和静态吸附容

量的变化趋势是一致的，而对于同种染料，QACC 的动态吸附容量均大于其相应

的静态吸附容量。

通过实验研究了 QACC 对直接湖兰 5B、酸性红 B和酸性嫩黄 G这三种染料

的吸附等温线。实验数据表明：QACC 吸附更符合 Langmuir 吸附等温式，运用

Langmuir 吸附方程式拟合的相关系数 R2分别为 0.9927、0.9958 和0.9992，而运用

Freundlich 吸附方程式拟合的相关系数 R2分别为 0.9352、0.7424 和0.9968。

本论文研究了 QACC 吸附的动力学性质，试验表明 QACC 对直接湖兰 5B、

酸性红 B和酸性嫩黄 G的吸附过程更符合 Lagergren 一级速率方程，一级速率方

程的相关系数优于二级速率方程的相关系数，且根据一级速率方程所求得的吸附

速率常数在计算热力学参数时有很好的线性关系，而根据二级速率方程所求得的

吸附速率常数在计算热力学参数时没有规律的线性关系。且吸附速率随温度升高

而增大，QACC 对这三种染料的吸附活化能大小依次为：直接湖兰 5B20.94KJ/mol；

酸性红 B8.70 KJ/mol；酸性嫩黄 G23.10KJ/mol。

本论文研究了 QACC 吸附的热力学性质，以 QACC 吸附直接湖兰 5B、酸性

红B和酸性嫩黄 G为例，测定了 QACC 吸附这三种染料的热力学参数。三种染料

的吸附自由能△G均为负值，且随着温度的升高而变小，这说明 QACC 吸附染料

的过程是自发进行的，温度越高自发的程度越大。焓变△H和熵变ΔS 均为正值，

△H>0 表明吸附过程是吸热的，吸附过程中，QACC 功能基团与染料结合形成了

化学键，发生了化学反应；△S>0 表示 QACC 对染料的吸附既有物理吸附，也有

化学吸附，且以化学吸附为主。

本论文对 QACC 的吸附机理进行了初步探讨，以酸性嫩黄 G为例，分别用饱

和容量法和等摩尔连续变化法测定了 QACC 吸附酸性嫩黄 G的摩尔比，用吸附平

衡式列出了 QACC 吸附酸性嫩黄 G的反应过程，论述了反应原理。

本论文以酸性嫩黄 G为例，研究 QACC 解吸参数，实验表明最佳解吸条件是：

NaOH 溶液为解吸剂，浓度为 0.5mol/L，脱附温度为 25℃，脱附时间为 60min。实

验表明 QACC 具有很好的循环利用性能，经过 5次吸附+脱附，还具有良好的吸附

能力。这不仅降低了处理成本，提高了经济效益，且做到污染排放减量化。

关键词：季铵型阳离子纤维素水溶性有机污染物吸附性能应用性能

再生性能吸附容量动力学参数热力学参数吸附机理

ABSTRACT

Cellulose is the most abundant renewable resources on the earth，

which owns many

advantages, such as inexpensive, biodegradable and no pollution produced to ecological

environment. And cellulose is of great significance in solving the energy, resources and

environmental issues. Natural cellulose, which adsorption capacity is not strong, can

become good adsorption materials through physical and chemical modified , So studies

on modified cellulose have been the hot spots.

Quaternary ammonium cationic cellulose (QACC), a new environmental-friendly

material, was synthesized to adsorb water-soluble organic pollutants in the paper. Its

adsorption property, application performance, adsorption mechanism and regeneration

property were studied. Cotton cellulose after basified can be made into QACC with

3-chloro-2-hydroxypropyl trimethyl ammonium chloride (CHPT) in presence of alkali

for 4hrs at 75℃, using isopropyl alcohol as a dispersing agent,. Its nitrogen content was

1.71% and the substitution degree (DS) of R4N+was 0.243. The infrared spectrum was

confirmed by FT-IR,XRD and SEM analysis: δasR4N+1637 cm-1, υC-O-C1050 cm-1,

δC-H1386 cm-1, υC-H2916 cm-1.

In the paper, the method and technological parameter of QACC was studied by

orthogonal experiment. The optimum adsorption parameters is as follows: adsorption

temperature is 45℃, pH value is near neutral（ph5-7）, oscillation frequency is 120 r/min

and oscillation time is 60minrs.

Quaternary ammonium cationic cellulose can be used to adsorb water-soluble

organic contaminations which contain hydrophilic groups, such as carboxyl, sulfonic

group, hydroxyl group and amido. And these groups can form Lewis base in the water.

QACC adsorb Lewis base mainly by the formation of chemical bonds, with a strong

adsorption, rapid absorption speed, high pollutant removal.

QACC has a better saturated absorptive capability towards water-soluble organic

contaminations which contain carboxyl, sulfonic group, hydroxyl group and amido at

45℃in near neutral water solution.. The saturated adsorption capacities of QACC were:

Direct Sky Blue 5B(C.I.24400) 486 mg/g , Acid Red B(C.I.14720) 474mg/g and Acid

light Yellow G(C.I.18820) 431 mg/g ,phenol 22mg/g,alpha naphthol 33mg/g, aniline

10mg/g, sulfanilic acid 23mg/g, 2-Hydroxy-3-naphthoic acid 24.4mg/g, R salt 37.7

mg/g , 2-naphthalene sulfonic acid 52mg/g, 1-Naphthoic acid 33mg/g, and sodium

dodecylbenzene sulfonate 168 mg/g.

Dynamic breakthrough curves indicate that the change trends of dynamic adsorp

-tion capacity are consistent with that of static adsorption capacity of QACC to different

dyes, and to the same kind of dye the dynamic adsorption capacity of QACC is greater

than its static adsorption capacity.

The adsorption isotherm of Direct Sky Blue 5B, Acid Red B and Acid light Yellow

G was studied. The results indicated that the adsorption isotherm of QACC accorded

with the Langmuir adsorption equation. The correlation coefficient of Langmuir

equation was 0.9927、0.9958 and 0.9992 respectively, while that of Freundlich equation

was 0.9352、0.7424 and 0.9968 respectively.

The kinetic properties of QACC were also studied in this article. The results

showed that the adsorption course of Direct Sky Blue 5B,Acid Red B and Acid light

Yellow G followed the first-order lagergren equation. The correlation coefficients of

their first-order lagergren equation were larger than their second-order correlation

coefficient. And adsorb rate constants according to the first-order kinetic model had

better linear relation than which according to the second-order kinetic model in

thermodynamic parameter experiments. Furthermore the adsorption rate constants

increase with increasing temperature. And activation energy of adsorption of Direct Sky

Blue 5B, Acid Red B and Acid light Yellow G was 20.94 、8.70and23.10KJ/mol

respectively.

In this paper, the thermodynamic properties of QACC were studied too. The therm

-odynamic parameters of QACC adsorbing Direct Sky Blue 5B,Acid Red B and Acid

light Yellow G were determined. Adsorption free energy(△G) of the three dyes are

negative, and become smaller with the rising of temperature.The adsorption process of

QACC to the tree dyes is spontaneous, and the higher the temperature, the greater the

degree of spontaneous. Enthalpy(△H) and entropy change(ΔS) are positive, △H> 0

indicates that the adsorption process is endothermic. The functional groups of QACC

formed a bond with dye and took place chemical reaction in the adsorption

process.△S>0 indicates that QACC adsorbing dyes are both physical adsorption and

chemical adsorption, and the chemical adsorption is main.

In this paper, the adsorption mechanism of the QACC was confirmed initially.

Using Acid light Yellow G as an example, the mole ratio of QACC was determined by

the saturation capacity and the continuous change, the reaction process of QACC was

listed with adsorption equilibrium formula and the reaction principle was discussed.

In this paper, Acid light Yellow G was used to study desorption parameters of

QACC. The experiments showed that the best conditions are: desorption is NaOH

solution, concentration is 0.5 mol/L, desorption temperature is 25℃, desorption time is

1 hrs. QACC has a good recycling properties and its adsorption capacities are still large

after regenerating for 5 times. This not only reduces the cost of processing and improves

the economic efficiency, but also achieves pollution reduction.

Key words: quarternary ammonium cationic cellulose, water-soluble

organic pollutants, adsorption property, application per

-formance, regeneration property, adsorption capacity,

kinetic parameter, thermodynamic parameter, adsorption

mechanism

中文摘要

ABSTRACT

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

§1.1 纤维素简介 ....................................................................................................... 1

§1.1.1 纤维素来源及应用 ............................................................................... 1

§1.1.2 纤维素的化学结构 ............................................................................... 2

§1.1.3 纤维素的结晶度和可及度 ................................................................... 2

§1.1.4 纤维素的物理性质 ............................................................................... 3

§1.1.5 纤维素与水的作用 ............................................................................... 4

§1.1.6 纤维素的化学性质 ............................................................................... 4

§1.2 纤维素改性 ....................................................................................................... 7

§1.2.1 纤维素改性原理 ................................................................................... 7

§1.2.2 纤维素物理改性方法 ........................................................................... 7

§1.2.3 纤维素化学改性方法 ........................................................................... 8

§1.2.4 纤维素的化学改性溶剂 ....................................................................... 9

§1.3 吸附的基本类型和影响吸附的因素 ............................................................... 9

§1.3.1 吸附机理及吸附类型 ........................................................................... 9

§1.3.2 影响吸附的因素 ................................................................................. 10

§1.4 纤维素吸附剂 ................................................................................................. 12

§1.4.1 纤维素吸附剂的分类及其国内外研究进展 ..................................... 12

§1.4.2 纤维素吸附剂的应用 ......................................................................... 14

§1.5 季铵型阳离子纤维素简介及国内外研究进展 ............................................. 15

§1.6 本论文的指导思想和研究目的 ..................................................................... 16

§1.7 本论文的主要研究内容 ................................................................................. 17

第二章实验部分 ....................................................18

§2.1 实验仪器及试剂 ............................................................................................... 18

§2.1.1 主要实验仪器 ......................................................................................18

§2.1.2 主要实验材料与试剂 ......................................................................... 18

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

§2.2.1 季铵型阳离子纤维素的制备方法 ..................................................... 18

§2.2.2 季铵型阳离子纤维素含氮量的测定方法 ......................................... 19

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摘要：

摘要纤维素是地球上最丰富的可再生资源，具有价廉、可降解和对生态环境不产生污染等优点，在解决人类所面临的能源、资源和环境问题方面具有重要意义。但天然纤维素的吸附能力并不强，必须经过物理化学改性才能成为性能良好的吸附材料，所以纤维素的功能化一直是人们研究的热点。本论文合成了一种吸附水溶性有机污染物的新型环境友好材料—季铵型阳离子纤维素（QACC），研究了其吸附性能、应用性能、吸附机理及其解吸再生性能。棉纤维素碱化后，以异丙醇为分散剂，以3-氯-2-羟丙基三甲基氯化铵（CHPT）为醚化剂，在75℃下反应4h制得QACC，测得其含氮量为1.71％。本论文应用正交实验研究了吸附工艺参数对QACC吸附容量...

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