头孢类抗生素在改性活性炭上的吸附

发布时间：2018-04-10 11:29

本文选题：活性炭 + 改性　；参考：《北京化工大学》2015年硕士论文

【摘要】：近几十年来,抗生素的污染问题受到了越来越广泛的关注,尤其是在饮用水中抗生素类物质也被检测到,对人类和生态环境造成很大的威胁。因此研究如何去除这类水体污染物是势在必行的。本文选择不同方法对活性炭进行改性,对比了不同改性活性炭的吸附效果。选择吸附效果较好的AC-Cu、AC-Fe和AC-Al,作为后面实验的研究对象。首先对三种活性炭进行了表面结构和性质的分析。结果表明,经过三种浸渍改性后,活性炭的表面变得更粗糙。其中AC-Cu的比表面积降低较小,增加了碳碳双键和芳香环类官能团。AC-Fe的比表面积的减少量与AC-Cu的相似,而表面的芳香环类官能团和羧基等含氧官能团都有所减少。AC-Al比表面积降低最大,羟基和羧基等含氧官能团都有所增加。并且在三种活性炭上都有相应的金属元素的存在。研究了不同条件对三种活性炭吸附头孢他啶效果的影响。结果表明,离子强度的升高,头孢他啶的吸附量会有所升高。而随着pH值的升高,三种活性炭对头孢他啶的吸附会明显降低。低温更有利于吸附的进行。天然有机物腐植酸的存在并不会对头孢他啶的吸附产生较大的影响。三种活性炭吸附头孢他啶符合准二级动力学模型。采用准二级动力学计算出的AC-Cu对头孢他啶的最大吸附量分别为200.0 mg·g-1(298 K)、196.1 mg.g-1(303 K)和185.2 mg·g-1(308 K),远高于AC-Fe和AC-A1对头孢他啶的吸附量。头孢他啶在吸附过程中主要受颗粒内扩散和液膜扩散两个过程控制。通过吸附等温线及热力学分析,发现吸附过程均为自发的、放热的,且可较好符合Freundlich和Tempkin等温方程。
[Abstract]:In recent decades, more and more attention has been paid to the contamination of antibiotics, especially the detection of antibiotics in drinking water, which poses a great threat to human beings and the ecological environment.Therefore, it is imperative to study how to remove these water pollutants.In this paper, different methods were chosen to modify activated carbon, and the adsorption effect of different modified activated carbon was compared.AC-CuCU AC-Fe and AC-Al, which have better adsorption effect, were selected as the experimental objects.Firstly, the surface structure and properties of three activated carbon were analyzed.The results show that the surface of activated carbon becomes rougher after three kinds of impregnation modification.The decrease of specific surface area of AC-Cu was smaller, and the decrease of specific surface area of carbon / carbon double bond and aromatic ring functional group. AC-Fe was similar to that of AC-Cu.On the other hand, the oxygen functional groups such as aromatic ring group and carboxyl group on the surface were decreased. The specific surface area of AC-Al decreased the most, and the oxygen functional groups such as hydroxyl group and carboxyl group increased.And there are corresponding metal elements on three kinds of activated carbon.The effects of different conditions on the adsorption of ceftazidime by three kinds of activated carbon were studied.The results showed that the adsorption capacity of ceftazidime increased with the increase of ionic strength.With the increase of pH, the adsorption of ceftazidime to ceftazidime was significantly decreased.Low temperature is more favorable for adsorption.The presence of natural organic humic acid does not affect the adsorption of ceftazidime.The adsorption of ceftazidime by three kinds of activated carbon was in accordance with the quasi-second-order kinetic model.The maximum adsorption amounts of ceftazidime to ceftazidime by quasi second-order kinetics were 200.0 mg / g ~ (-1) K ~ (-1) and 185.2 mg / g ~ (-1) ~ 308K ~ (-1), respectively, which was much higher than that of AC-Fe and AC-A1 for ceftazidime.Ceftazidime adsorption is mainly controlled by intragranular diffusion and liquid film diffusion.Through adsorption isotherm and thermodynamic analysis, it is found that the adsorption process is spontaneous and exothermic, and can well accord with Freundlich and Tempkin isothermal equations.
【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ424.1;X703

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