【作者】 王杨；

【导师】 邢永恒；

【作者基本信息】 辽宁师范大学 ， 无机化学， 2018， 硕士

【摘要】 随着化石燃料储存量减少,人们迫切地需要一种新型能源代替化石燃料,而核能具有绿色环保且高效等优点,成为未来最有希望取代化石燃料的主要能源。因此,大力发展核能,就需要大量开采铀,铀是一种具有放射性的元素。在发展核能的过程中不可避免的造成了铀污染,因此需要寻找一种有效的方法处理含铀废水。在众多处理方法中,吸附法因具有操作简单,成本较低等优点进入了科学家们的视线。使用吸附法处理废水需要寻找一种高效、环保、廉价的吸附剂。壳聚糖作为一种廉价的生物质材料,是一种较理想的吸附剂,但是壳聚糖自身机械强度不高,不耐酸,需要对其结构进行改性。在改性的同时,还可以有针对性的设计壳聚糖材料的结构,增加其表面积,从而提高改性壳聚糖的吸附能力。为了更好的设计具有高吸附性的铀酰吸附剂,需要研究整个吸附过程的反应机理。目前已有大量关于改性壳聚糖吸附铀酰的报道,但是关于其吸附机理的报道较少,目前大部分学者认为铀酰离子在水溶液中与吸附剂之间可能存在化学作用,如配位作用。因此,寻找更加高效廉价的吸附剂并研究其吸附机理具有实际应用前景。基于上述思想,有必要从两方面着手:开发金属框架化合物,研究它的配位机制;开发廉价无污染的高效吸附剂。本论文合成了两种改性壳聚糖材料,通过红外光谱、热重分析、扫描电镜和PXRD表征了这两种材料的结构。初步探讨了p H,时间,吸附剂投入量等因素对吸附性能的影响。同时设计合成四种结构不同的铀酰配合物。利用X-Ray单晶衍射测定晶体结构,利用IR、TG、紫外和元素分析等方法对其进行了表征,同时研究了配合物对染料的吸附性能。更多还原

【Abstract】 With the reduction of fossil fuel reserves,people urgently need a new energy source which is green and efficient to replace the fossil fuels.The nuclear energy is the most promising alternative to replace the fossil fuel as the main energy source in the future.To develop nuclear energy,we need a large amount of uranium.Uranium,as a radioactive element,is the main material of nuclear energy.It is unavoidable to cause the uranium contamination in the environment during the development of nuclear energy.So it is necessary to find an effective method to treat uranium-contained wastewater.Among the numerous methods,adsorption causes widespread concern because of the advantages such as the simple operation and the low cost.It is necessary to find a highly efficient,environmentally friendly and cheap adsorbent for treating wastewater by adsorption.As an inexpensive biomass material,chitosan is an ideal adsorbent.However,chitosan need to be modified because of its poor mechanical strength and acid resistance.At the same time,the structure of the chitosan material can be designed to increase the surface area and improve the adsorption capacity.In order to find a uranyl adsorbent with high adsorbability,it is necessary to study the reaction mechanism of the whole adsorption process.There are many reports about the adsorption of uranyl by modified chitosan.While,there are few reports about its adsorption mechanism.Most scholars believe that there may be chemical interactions between uranyl ions and adsorbents in aqueous solution,such as coordination.Therefore,it is useful to look for more efficient and cheap adsorbents and study their adsorption mechanism.Based on the above ideas,it is necessary to proceed from two aspects:develop metal framework complexes and study its coordination mechanism;develop inexpensive,pollution-free and high-efficiency adsorbent materials.Two kinds of modified chitosan were synthesized in this paper.The structure of the two materials was characterized by infrared spectroscopy,thermogravimetry,scanning electron microscopy and PXRD.The effects of pH,adsorption time,adsorbent input and other factors on the adsorption properties were preliminarily discussed.Four kinds of uranyl complexes with different structures were designed and synthesized.The crystal structure was confirmed by X-Ray single crystal diffraction,infrared spectroscopy,UV-vis,thermogravimetry and elemental analysis.Meanwhile,the adsorption properties of complexes on dyes were also studied.更多还原