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Ni、B共掺杂TiO2-陶粒光催化降解染料废水研究 总被引:3,自引:0,他引:3
采用溶胶一凝胶法制备陶粒负载Ni2O3和B元素共掺杂纳米TiO2可见光催化剂,以甲基橙为目标降解物,探讨了光催化氧化降解甲基橙的规律,考察了催化剂的焙烧温度、Ni元素和B元素掺杂量、催化荆投加量、甲基橙溶液初始浓度、初始pH值、反应温度等因素对甲基橙脱色效果的影响。结果表明:在600℃温度下焙烧的催化剂具有最佳光催化活性;B和Ni最佳掺杂量为3.0%;甲基橙脱色率随甲基橙初始浓度的降低、催化剂投加量的增加、反应温度的升高、初始pH值降低而增大;催化剂经重复使用后,仍具有较高的光催化性能。 相似文献
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Municipal wastewaters taken from a primary sedimentation tank were subjected to different chemical oxidation processes (ozonation or UV radiation alone or combined with hydrogen peroxide) to observe the evolution of COD and BOD/COD ratios. Ozonation of wastewater led to different increases of COD level reduction depending on pH and carbonate‐bicarbonate ion concentrations. Direct photolysis or hydrogen peroxide alone were found to be inappropriate technologies. On the other hand, advanced chemical oxidation, that is, oxidation with ozone or UV radiation combined with hydrogen peroxide, increased COD level reduction only when wastewater was previously decarbonated. Thus, elimination of carbonate‐bicarbonate ions, increase of pH and addition of hydrogen peroxide (10‐3 M) yield increases COD level reduction rates. Finally, preozonation also allows improvement of wastewater biodegradability. 相似文献
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废水中一般会有离子存在,而离子对于TiO2光催化作用的影响是非常显著的。对于水体中常见的阳离子、阴离子、高浓度和多种离子共存的影响进行了归纳和分析,其中对于高浓度和多种离子共存的影响进行探讨是较少见报道的。此简述以期为相关研究的拓展提供参考。 相似文献
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纳米TiO2薄膜耦合光催化氧化还原反应脱除水中无机氮 总被引:2,自引:2,他引:2
由溶胶-凝胶法制备了固定化二氧化钛薄膜,研究了薄膜催化剂光催化脱除含氨氮-亚硝酸氮混合液中无机氮的活性。考察了溶胶制备工艺、催化反应条件(尤其pH)对光催化活性的影响。实验证明:酸性条件有利于亚硝酸氮的还原,碱性条件有利于氨氮的氧化,通过调节pH可以获得光催化氧化氨氮和还原亚硝酸氮耦合效果。如果加入甲酸维持酸性条件,反应0.5h后再将pH调回碱性,可以大大提高光催化脱氮的效果:经过2h的光催化反应,二氧化钛膜催化总氮去除率可达50%以上。经多次试验证明附载二氧化钛薄膜不脱落,光催化活性未见减弱,可重复利用。提出了光催化脱氮的反应机理。 相似文献
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掺杂纳米TiO2在难降解废水处理中的研究进展 总被引:4,自引:0,他引:4
掺杂可有效改善纳米TiO2的光催化活性及其光利用率,利于光催化技术在工业生产中的应用推广.介绍了掺杂纳米TiO2的光催化机理,总结了常见的掺杂纳米TiO2的制备方法:溶胶-凝胶法、浸渍法等.阐述了TiO2光催化技术在印染废水、农药废水、造纸废水及工业无机废水处理中的应用,并进一步分析了该研究领域所存在的问题,为今后光催化技术的发展方向提出展望:寻求新的掺杂离子、研制掺杂负载型纳米光催化剂和加强降解机理研究等. 相似文献
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Conversion of vegetable oils predominantly composed of triglycerides using pyrolysis type reactions represents a promising option for the production of renewable fuels and chemicals. The purpose of this article was to compare catalytic cracking with thermal cracking on production of gaseous hydrocarbon and gasoline conversion by cottonseed oil, and to discuss the difference on composition of products from catalytic cracking and thermal cracking. Reaction products are heavily dependant on the catalyst type (catalyst activation) and reaction conditions. They can range from dry gas to light distillate, such as dry gas, liquefied petroleum gas and gasoline. When the temperature of catalytic cracking is over 460 °C, the effects of thermal cracking must be considerable. 相似文献
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Cátia Liane Ücker Suelen R. Almeida Marcelo L. Vitale Fábio C. Riemke Mateus M. Ferrer Eduardo C. Moreira Cristiane W. Raubach Sergio Cava 《International Journal of Applied Ceramic Technology》2023,20(3):1963-1977
Microwave-assisted hydrothermal synthesis of aluminum (Al)-doped TiO2 (ALT) and niobium (Nb)-doped TiO2 (NBT) nanoparticles were carried out. Investigations were performed to examine the crystallinity, vibrational modes, surface morphology, and composition using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS), respectively. The XRD study indicated the higher crystallinity of the ALT particles compared to the Al and Nb-doped TiO2 (ALNBT) particles, and only the presence of the anatase phase was observed in all samples. As a result of doping, the Raman mode at ∼147 cm−1 is found to be shifted toward a higher wavenumber for both samples. SEM analysis showed the spherical morphology of ALT and NBT nanoparticles. The elemental composition peaks of Al, titanium, Nb, and oxygen were noticed by EDS measurements. Furthermore, both prepared nanoparticles were used as photocatalytic materials. The Nb and Al-doped samples showed an improvement in the photocatalysis response in relation to the pure TiO2 sample, in which Al-doped sample was able to decolorize 100% of rhodamine B in 75 min of analysis. 相似文献
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TiO2纳米粒子是一种N型半导体材料,因其具有高活性、稳定性、生物相容性而成为最受重视的一种光催化纳米材料,得到了广泛应用。但由于其存在禁带宽度较大,电子受激发跃迁时产生的电子和空穴十分容易复合等问题,影响光了催化效率,制约着其进一步发展。目前,如何提高TiO2纳米粒子的光催化效率成为材料研究中的热点,是研究的核心课题之一。本文介绍了TiO2纳米粒子的光催化原理,系统综述了TiO2纳米粒子的制备方法;同时总结了提高TiO2纳米粒子光催化效率的方法,并介绍其在生产生活中的应用。 相似文献
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J. Araa J. A. Herrera Melin J. M. Doa Rodríguez O. Gonzlez Díaz A. Viera J. Prez Pea P. M. Marrero Sosa V. Espino Jimnez 《Catalysis Today》2002,76(2-4):279-289
Solar TiO2-photocatalysis was applied to waters from a natural wastewater treatment plant located in the Universidad de Las Palmas de Gran Canaria. Degussa P-25 TiO2 and its mixture with activated carbon (AC–TiO2) were used as catalysts. The presence of ozone and certain ions such as phosphates on the photocatalytic degradation of organic matter was also studied.
Disinfection experiments have provided interesting results, particularly when using the catalyst AC–TiO2 and ozone, since total disinfection was achieved in less than 60 min. No bacterial reappearance at 24 or 48 h was observed. Additionally, this catalyst gave important TOC and some ions concentrations reductions.
Studies in catalyst reuse revealed that the catalyst AC–TiO2 showed almost no deactivation. 相似文献
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在稀硫酸溶液中的阳极氧化钛箔,采用混合增长模型技术控制氧化膜的生长,制备了TiO2光催化薄膜,TiO2薄膜通过苯酚的光催化降解实验检验,具有较高的催化活性及很好的催化稳定性,实验结果表明:阳极氧化法固定TiO2薄膜切实地,不仅解决了TiO2微粒光催化过程催化剂微料与水难分离的问题,而且阳极氧化制膜所需时间短(几秒到几分)、工艺简单,十分有利于工业化制备。 相似文献
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掺Ag,Ni对TiO2气相光催化活性的影响 总被引:3,自引:1,他引:3
采用溶胶-凝胶法制备了以活性炭为载体的负载型Ag/TiO2及Ni/TiO2光催化剂,以气相中甲苯降解反应考察了两种催化剂的活性随金属离子掺杂量的变化. 用透射电镜、X射线衍射及荧光光谱对掺杂催化剂进行了表征. 结果表明,经Ag, Ni掺杂后,Ag/TiO2和Ni/TiO2两种催化剂的催化活性均有不同程度的提高,且Ni/TiO2优于Ag/TiO2. 两种催化剂的最佳掺杂量均为0.4%. 根据表征及实验结果分析了金属离子不同掺杂量影响TiO2光催化活性的机理. 相似文献