【作者】 王丽霞；

【导师】 郭志超；

【作者基本信息】 天津科技大学 ， 化学工程， 2020， 硕士

【摘要】 目前,许多的科研人员虽然开发出多种制备及改性二氧化钛催化剂的方法,并且在一定程度上提高了二氧化钛的光催化性能。但是,目前的制备及改性方法大多数存在着耗时长、耗能高、生成物易团聚等问题,并且制备出的产物需要进行长时间的高温煅烧的后续处理,导致了制备方法的复杂化。本文以TiO₂作为研究对象,在微波场中,通过添加搅拌,利用动态法制备TiO₂,并研究微波场中工艺条件对产品形貌的影响。微波动态法的优势在于反应过程中可随时进行反应条件的监控与调节,并且反应过程中伴随着持续稳定性的搅拌,使反应物均匀受热,避免产生局部过热等问题。同时,相较于静态法,可以加快成核速率和传质速率,使得晶体在有限的时间内充分生长,结晶更加的完全,分散性更加良好。本文探索了微波输入能量、反应时间、矿化剂量等因素对TiO₂产品的光催化活性的影响进,从而确定了最佳的制备条件,并且对实验条件TiO₂的形貌影响进行了相应的机理分析。通过研究发现:在微波场中,能够利用动态法,合成具有介孔结构的纳米二氧化钛。在微波场中,相同的温度、反应时间及矿化剂量的条件下,二氧化钛结晶度随着微波功率的升高逐渐升高,比表面积逐渐增大,光催化降解罗丹明B的效果显著提升。制备出的二氧化钛属于锐钛矿型。同时,固定其他反应条件,通过实验可发现随着矿化剂的添加量增加,二氧化钛的光催化降解效果逐渐升高。本文同时研究了在微波动态法的条件下,固定反应条件,添加表面活性剂CTAB对所制备的TiO₂形貌的影响。研究发现CTAB的添加量对所制备的二氧化钛形貌、结晶性能等指标均有较大的影响,随着CTAB量的增加至8g/L时,二氧化钛微球形貌逐渐清晰,继续增加CTAB量时,二氧化钛微球形貌逐渐呈现不规则化,且团聚现象逐渐加重。同时,二氧化钛微球的光催化降解效果随CTAB的添加量呈现出先升高后降低的趋势。更多还原

【Abstract】 At present,although many researchers have developed a variety of methods to prepare andmodify titanium dioxide catalyst,and to a certain extent,have improved the photo catalytic performance of titanium dioxide.However,most of the current preparation and modification methods have such problems as long time consuming,high energy consumption and easy agglomeration of products.Moreover,the prepared products need to undergo long-term follow-up treatment of high-temperature calcinations,which leads to the complexity of the preparation methods.In this study,the microwave dynamic method is used to prepare TiO₂and the morphology of the product is adjusted in microwave field.Meanwhile,it is also studied to adjust the morphology of the prepared TiO₂by adding a Surfactant to optimize the preparation method of TiO₂catalyst with high photo catalytic ability.The advantage of microwave dynamic method is that the reaction conditions can be monitored and adjusted at any time during the reaction process,and the reaction process is accompanied by continuous and stable stirring,so that the reactants are uniformly heated,and local overheating is avoided.Compared with the static method,At the same time,compared with the static method,it can accelerate the nucleation rate and mass transfer rate,so that the crystal can fully grow in a limited time,the crystallization is more complete,and the dispersion is better.This article explored the influence of microwave input energy,reaction time,mineralization dose and other factors on the photo catalytic activity of TiO₂products,so as to determine the best preparation conditions,and the corresponding mechanism analysis of the experimental conditions on the morphology of TiO₂.The study found:In microwave field,nano-TiO₂with mesoporous structure can be synthesized by dynamic method.In the microwave field,under the same temperature,reaction time and mineralization dose,the crystallinity and specific surface area of titanium dioxide gradually increased with the increase of microwave power,and the photocatalytic degradation effect of Rhodamine B was significantly improved.The prepared titanium dioxide belongs to anatase type.At the same time,fixing other reaction conditions,it can be found that the photocatalytic degradation effect of titanium dioxide gradually increases with the increase of mineralizer.At the same time,the effects of microwave dynamic method,fixed reaction conditions and Surfactant CTAB on the morphology of TiO₂were studied.It was found that the amount of CTAB had a great influence on the morphology and crystallinity of the prepared titanium dioxide.With the increase of CTAB content to 8g/L,the morphology of titanium dioxide microspheres gradually became clear.When the amount of CTAB continued to increase,the morphology of titanium dioxide microspheres gradually became irregular,and the agglomeration phenomenon gradually aggravated.At the same time,the photocatalytic degradation effect of TiO₂microspheres increased at first and then decreased with the addition of CTAB.更多还原