摘要随着现代化进程的加快，含重金属冶金废水的排放量增多，环境污染越来越严重，重金属污染急需解决。本文以丰富易得的低成本原料硅藻土为吸附剂，用CaCO3进行改性，以提高硅藻土对重金属的吸附性能，并用扫描电镜对改性前后硅藻土进行了形貌分析。实验研究得出，改性硅藻土的表面具有更多的微米级孔结构；改性硅藻土对重金属离子的吸附表现为：在50℃，改性硅藻土用量为10 g/L，pH值为5。5，Cu2+初始浓度均为2 mmol/L，吸附1 h的条件下，对Cu2+的去除效果更好，去除率高达98。06%；在20℃，改性硅藻土用量为10 g/L，pH值为5。5，Zn2+和Cr3+初始浓度均为2 mmol/L，吸附1 h的条件下，对Zn2+和Cr3+的去除效果更好，去除率分别高达97。31%、93。891%；在20℃，改性硅藻土用量为10 g/L，pH值为5。5，Pb2+初始浓度均为2 mmol/L，吸附2 h的条件下，对Pb2+的去除效果更好，去除率高达99。81%。87362
本实验进一步研究了改性硅藻土吸附重金属离子的动力学行为，吸附过程符合伪二阶动力学模型；建立了等温吸附模型，得出改性硅藻土吸附重金属离子的热力学行为满足Langmuir等温方程。
毕业论文关键词：硅藻土；改性；吸附；重金属
ABSTRACT With the accelerated development of modernization, metallurgical waste containing heavy metals emissions increase, more and more serious environmental pollution, heavy metal pollution need to be resolved。
In the paper, abundant and easily available low-cost raw material diatomite as the adsorbent, with CaCO3 modified to improve the performance of the diatomite adsorption of heavy metals, and byscanning electron microscopy before and after modification diatomite morphology analysis。Experimental study concluded that having moresurface-modified diatomite micron pore structure,and Modified Diatomite performance for heavy metal ions as follows: at 50℃, modified diatomaceous earth in an amount of 10 g / L, pH value of 5。5, Cu2+ initial concentration was 2 mmol / L, adsorption conditions under 1 h on Cu2+ removal better, removal of up to 98。06%; at 20 ℃, modified diatomaceous earth in an amount of 10 g / L, pH value of 5。5, Zn2+ and Cr3+ initial concentration was 2 mmol / L, adsorption 1 h under the conditions of Zn2+ and Cr3+ removal better removal rates were as high as 97。31%, 93。891%; at 20 ℃, modified diatomaceous earth in an amount of 10 g / L, pH value of 5。5, Pb2+ initial concentrations of 2 mmol / L, adsorption under 2 h, more preferably of Pb2+ removal rates as high as 99。81%。In this study, further study of the dynamical behavior of the modified diatomite adsorption of heavy metal ions, the adsorption process in line with the pseudo-second order kinetic model; established isotherm model, draw the thermodynamic behavior of heavy metal ions adsorption by Diatomite meet Langmuir equation 。
Key words: diatomite; modified; adsorption; heavy met
目录
第一章 绪论 1
1。1 重金属污染概述 1
1。1。1 重金属污染现状 1
1。1。2 含重金属废水的来源与危害 1
1。2 重金属废水的处理方法以及国内外应用研究 2
1。2。1 重金属废水的处理方法 2
1。2。2 硅藻土在国内外的研究现状 3
1。3 论文研究的目的和意义 6
1。4 本文研究的主要内容 6
第二章 实验部分 8
2。1 实验试剂 8
2。2 实验仪器 8
2。3 实验方法 8
2。3。1 Cu2+标准溶液的配制和工作曲线的绘制 8
2。3。2 Zn2+标准溶液的配制和工作曲线的绘制 9 硅藻土对冶金废水中重金属离子的吸附研究:http://www.youerw.com/huaxue/lunwen_134748.html