电气石粉对颜料废水脱色的研究毕业论文
2021-03-21 23:58:11
摘 要
电气石(Tourmaline)因其具有的天然电极性、红外辐射性以及热电性和压电性,使其成为一种重要的环境功能材料,在医疗健康、环境保护和建筑材料等领域均有较大的应用前景,但目前对电气石的用途还存在较多的未知性,对电气石的开发利用还未得到足够的重视。我国是人口大国,水资源现状极其堪忧,但随着颜料化工行业的发展,每年均消耗大量的颜料,同时产生了大量的颜料废水,对自然水体造成了极其严重的危害,加剧了我国的水资源现状,颜料废水亟待处理。而在我国电气石资源储量巨大,分布广泛,且其对环境无污染,故本文将电气石应用于颜料废水的处理,期望为环境保护做出贡献。
本文选用两种不同产地电气石,分别对阳离子蓝溶液进行吸附,探究粒度、投加量、吸附时间、溶液初始浓度、pH值和温度等因素对吸附过程的影响。并以所得试验数据,进行动力学和热力学研究,探讨电气石吸附阳离子蓝的脱色机理。可得到下列结论。
在25℃、pH=8、吸附时间为90min的条件下,当1号电气石的投加量为500mg时,对10mg/L的阳离子蓝溶液的脱色率可达96.88%,吸附量为0.97mg/g;在25℃、pH=8、吸附时间为90min的条件下,当2号电气石的投加量为800mg时,对10mg/L的阳离子蓝溶液的脱色率可达95.79%,吸附量为0.6mg/g,脱色效果基本完全。
1号电气石吸附阳离子蓝的过程,符合准二级动力学模型和Freundiich等温吸附模型,△G均小于0,吸附过程为自发过程;吸附焓变△Hlt;0,为放热过程;熵变△Slt;0,为熵减小的过程。
2号电气石吸附阳离子蓝的过程,符合准二级动力学模型和Langmuir等温吸附模型,△G均大于0,为非自发进行过程,主要为物理吸附;吸附焓变△Hgt;0,为吸热过程,熵变△Sgt;0,为熵增过程。
本文通过试验数据和研究,得出电气石对颜料的脱色作用主要通过三种机制:矿物表面吸附、极性吸附和羟基自由基的氧化,共同作用而达到理想脱色效果,
关键词:电气石;阳离子蓝;吸附机理;
Abstract
Tourmaline has become a kind of important environmental functional material because of its natural electrode, infrared radiation, hot spots and piezoelectricity. In medical, health,environmental protection and building materials and other fields have greater application prospects, but the use of tourmaline is still unknown, and the development and utilization of tourmaline has not been paid enough attention to.China is a country with a large population, its water resources situation is very worrying, but with the rapid development of dyestuff industry, the annual consumption of a large number of dye, the dye waste water produced at the same time, causing serious damage to the natural water, aggravating the situation of water resources in our country,so urgent treatment of dye wastewater is needed. In China, the reserves of tourmaline resources are huge, the distribution is extensive, and the environment is free from pollution. Therefore, tourmaline should be used in the treatment of dye wastewater, and it is expected to contribute to environmental protection.
In this paper, two kinds of tourmaline from different habitats were selected to adsorb the cationic blue solution. The effects of particle size, dosage, adsorption time, initial concentration of solution, pH value and temperature on the adsorption process were investigated. Based on the experimental data, the kinetic and thermodynamic studies were carried out to investigate the decolorization mechanism of tourmaline adsorbed cationic blue.
At 25 C, pH=8, adsorption time is 90min, when the 1# tourmaline dosage is 500mg, decolorization of cationic blue 10mg/L solution on the rate of up to 96.88%, the adsorption capacity for 0.97mg/g; at 25 C, pH=8, adsorption time is 90min, when the 2# tourmaline dosage the amount of 800mg, decolorization of cationic blue solution on the 10mg/L rate of up to 95.79%, the adsorption capacity was 0.6mg/g, the decolorization effect completely.
The process of No. 1tourmaline adsorbs cationic blue, pseudo two order kinetics model on adsorption kinetics, Freundiich adsorption isotherm model in thermodynamics, the G value was less than 0,so the adsorption process was spontaneous process; the adsorption enthalpy change of Hlt;0 was an exothermic process; entropy Slt;0, as entropy reducing process.
The process of No. 2 tourmaline adsorbs cationic blue, pseudo two order kinetics model on adsorption kinetics, Langmuir adsorption isotherm model in thermodynamics, the G value was greater than 0, is a non spontaneous process, mainly for physical adsorption; adsorption enthalpy change Hgt;0 for heat absorption process, entropy Sgt;0, for entropy increase process.
In this paper, through the test data and research, the decolorization of dyes by tourmaline mainly through three mechanisms: oxidation and adsorption, polarity of mineral surface adsorption and hydroxyl radical, interaction and achieve ideal decolorization effect.
Key words:tourmaline; Cationic blue; adsorption mechanism
目 录
第一章 绪论 1
1.1电气石概述 1
1.1.1电气石的概念 1
1.1.2 电气石的特征 1
1.1.3电气石的性质 1
1.1.4电气石的研究与应用 2
1.2颜料废水概述 3
1.2.1颜料废水的特点及危害 3
1.2.2电气石在颜料废水脱色处理中的研究 3
1.3研究的意义和内容 4
第二章 试验材料、设备及研究方法 5
2.1试验原料 5
2.1.1电气石样品的制备 5
2.1.2电气石原料的化学成分 5
2.1.3电气石原料的XRD物相分析 6
2.2试验用颜料 7
2.2.1颜料特征 7
2.2.2模拟颜料废水的配置 7
2.3试验药剂 7
2.4试验仪器设备 8
第三章 1号电气石对阳离子蓝的脱色作用 9
3.1阳离子蓝颜料标准曲线 9
3.2粒度对脱色的影响 10
3.3时间对脱色的影响 10
3.4投加量对脱色的影响 11
3.5初始浓度对脱色的影响 12
3.6初始pH对脱色的影响 13
3.7温度对脱色的影响 14
3.8适宜条件试验 15
第四章 2号电气石对阳离子蓝的脱色作用 16
4.1 粒度对脱色的影响 16
4.2时间对脱色的影响 17
4.3投加量对脱色的影响 18
4.4初始浓度对脱色的影响 19
4.5初始pH对脱色的影响 20
4.6温度对脱色的影响 21
4.7适宜条件试验 21
第五章 电气石对阳离子蓝的动力学和热力学研究 22
5.1吸附动力学研究 22
5.1.1吸附动力学相关理论 22
5.1.2 1号电气石吸附阳离子蓝的动力学研究 23
5.1.3 2号电气石吸附阳离子蓝的动力学研究 25
5.2吸附热力学研究 27
5.2.1吸附热力学相关理论 27
5.2.2热力学参数 28
5.2.3 1号电气石对阳离子蓝的吸附等温模型 29
5.2.4 2号电气石对阳离子蓝的吸附等温模型 32
5.3小结 36
第六章 脱色机理 38
6.1红外光谱特征 38
6.2吸收光谱特征 39
6.3吸附机理分析 40
第七章 结论 41
致谢 42
参考文献 43
第一章 绪论
1.1电气石概述
1.1.1电气石的概念
电气石,英文名称为“Tourmaline”。在我国,宝石级电气石被称为“碧玺”,古人认为其有辟邪之意;然而更多的非宝石级电气石广泛分布于我国各地区,亟待研究与应用。
1.1.2 电气石的特征
电气石是一种环状硅酸盐晶体矿物[1],其成分和结构都十分复杂,因此很多矿物学家提出多种结构式,直至二十世纪五十年代确定其晶体结构后,才最终得出一个合理的结构式[2]:
XY3Z6Si6O[BO3]3W4
式中:X=Ca2 、Na 、K 、空位;
Y=Fe2 、Mg2 、Al3 、Li 、Mn2 、Fe3 、Mn3 、Cr3 、Ti4 ;
Z=Al3 、Mg2 、Cr3 、V3 ;