不同来源的纳米黑炭对泰乐菌素的吸附特性

发布时间：2018-04-09 17:16

本文选题：黑炭　切入点：针铁矿　出处：《安徽理工大学》2016年硕士论文

【摘要】：抗生素大量且广泛的应用于人畜疾病的预防治疗及动物饲料添加剂等领域,且其进入生物体后很难被完全吸收和消化,大部分的抗生素会以母体或其代谢物的形式通过尿液或粪便排出体外进入到环境中,因此给人类健康和生态环境造成危害。国内外研究者们对抗生素类污染物的环境行为开展了大量的研究,但是对抗生素在环境中迁移转化机制的认识仍不够全面,对于抗生素在多介质多界面上的吸附机理认识不足。因此本文以泰乐菌素(TYL)为研究对象,分别考察了黑炭对抗生素的吸附特性和机制以及环境中普遍存在的矿物和腐植酸与黑炭的界面作用对TYL迁移的影响,论文主要取得了以下几个成果：1.主要研究了TYL在三种不同来源的纳米黑炭上的吸附特性。研究发现：TYL在稻杆黑炭(RC)、燃油发动机飞灰(MC)和锅炉煤灰(SC)上的吸附分别于24h、24 h和12 h达到吸附平衡,二级动力学和颗粒扩散模型可以较好的拟合黑炭吸附TYL的动力学数据。用Slips模型拟合黑炭吸附TYL的等温线数据结果非常好,按吸附能力排序为RCMC SC。增大吸附溶液的pH值和离子强度都会降低纳米黑炭的吸附能力。TYL在纳米黑炭上吸附主要是疏水性分配作用、π-π EDA共用电子对作用、氢键作用和离子交换等作用共同作用。2.黑炭-针铁矿(BC-FeOOH)和黑炭-蒙脱石(BC-MT)界面作用对其吸附TYL的影响：通过各种表征(SEM、XRD、FTIR)研究了负载矿物前后的黑炭,研究发现黑炭与矿物的结合方式主要为化学方式。TYL在BC-FeOOH和BC-MT上的吸附分别于12h和24 h达到完全吸附平衡。改性后BC-FeOOH对TYL的最大吸附量达到了70625 mg/kg,是改性前针铁矿的9倍。BC-MT对TYL的累计吸附量可达到123221 mg/kg,是黑炭的1.5倍,是蒙脱石的3倍。TYL在BC. FeOOH、 FeOOH-BC、MT和MT-BC上的吸附数据用拉格朗日二级动力学模型的拟合效果较好,拟合的相关性系数(R2)达到0.997。BC-FeOOH吸附TYL的能力随着pH值的增加不断增强,BC-MT的吸附规律与之相反,并且两者的吸附能力会随着离子强度的增强而减弱。3.黑炭-腐殖酸界面作用对其吸附TYL的影响：通过各种表征手段(例如BET. SEM、 XRD、FTIR)研究了负载腐殖酸前后的黑炭,并且研究了两种黑炭RC和SC负载腐殖酸后(RC-HA、SC-HA)对TYL的吸附特性。TYL在RC-HA和SC-HA上吸附均于24h达到完全吸附平衡。改性后RC-HA对TYL的最大吸附量达到了107125 mg/kg,相比RC增长了32%,SC-HA对TYL的累计吸附量可达到30985mg/kg,相比SC增加了72%,按吸附能力排序为RC-HA RC SC-HA SC. TYL在RC-HA和SC-HA上吸附动力学数据用二级动力学方程拟合效果较好,这是化学作用作用的结果。等温线数据用Henry和Freundlich等温模型拟合较好,说明分配机制存在于吸附过程中。RC-HA和SC-HA吸附TYL的能力随着pH值和离子强度的增加而减小。
[Abstract]:Antibiotics are widely used in the prevention and treatment of human and animal diseases, animal feed additives and other fields, and it is difficult to be completely absorbed and digested after entering the organism.Most antibiotics are excreted into the environment by urine or faeces in the form of mother or its metabolites, thus causing harm to human health and ecological environment.Researchers at home and abroad have carried out a lot of research on the environmental behavior of antibiotic pollutants, but the mechanism of antibiotic migration and transformation in the environment is still not fully understood, and the mechanism of antibiotic adsorption on multi-medium and multi-interface is not fully understood.Therefore, the adsorption characteristics and mechanism of antibiotics on black charcoal and the effect of interfacial interaction between humic acid and black carbon on TYL migration were investigated.The thesis has made the following achievements: 1. 1.The adsorption properties of TYL on three different sources of black carbon nanoparticles were studied.It is found that the adsorption equilibrium of TYL on RCU (fuel engine fly ash) and boiler coal ash (SCC) reaches the equilibrium at 24 h and 12 h, respectively. The kinetic data of TYL adsorption on black carbon can be fitted well by the second-order kinetics and particle diffusion model.Slips model was used to fit the isotherm data of TYL adsorbed by black carbon, and the order of adsorption ability was RCMC SC.Increasing the pH value and ionic strength of the adsorbed solution can decrease the adsorption ability of nano-black carbon. The adsorption of TYL on the black carbon is mainly hydrophobic distribution, and 蟺-蟺 EDA shared electron pair, hydrogen bond and ion exchange.The effect of BC-FeOOHand BC-MTC on the adsorption of TYL was studied by using various characterizations of BC-FeOOH) and BC-MTC before and after loading minerals.It was found that the binding mode of black carbon to minerals was chemically. The adsorption of TYL on BC-FeOOH and BC-MT reached a complete adsorption equilibrium at 12 h and 24 h, respectively.The adsorption data on FeOOH, FeOOH-BCnmt and MT-BC were fitted well with Lagrangian second-order kinetic model. The fitted correlation coefficient was R2). The ability of 0.997.BC-FeOOH to adsorb TYL was enhanced with the increase of pH value. The adsorption law of BC-MT was opposite.And the adsorption capacity of the two will weaken with the increase of ionic strength.The effect of the interaction between black carbon and humic acid on the adsorption of TYL: by various means of characterization (such as BETs).The maximum adsorption capacity of modified RC-HA to TYL was 107125 mg / kg, compared with RC, the cumulative adsorption capacity of SC-HA on TYL was 30985 mg / kg, and that of SC was 72% higher than that of SC. The order of adsorption ability was RC-HA RC SC-HA SCS.The kinetic data of TYL adsorption on RC-HA and SC-HA were fitted well by the second-order kinetic equation, which was the result of chemical action.The isotherm data were fitted well by Henry and Freundlich isothermal models, which indicated that the distribution mechanism existed in the adsorption process. RC-HA and SC-HA decreased the adsorption ability of TYL with the increase of pH value and ionic strength.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O647.3;X703

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