首页 | 本学科首页   官方微博 | 高级检索  
     

La掺杂TiO2负载Pt催化剂制备及其室温氧化低浓度甲醛
引用本文:彭洪根,应家伟,张景岩,张先华,彭程,饶成,刘文明,张宁,王翔. La掺杂TiO2负载Pt催化剂制备及其室温氧化低浓度甲醛[J]. 催化学报, 2017, 38(1): 39-47. DOI: 10.1016/S1872-2067(16)62532-9
作者姓名:彭洪根  应家伟  张景岩  张先华  彭程  饶成  刘文明  张宁  王翔
作者单位:1. 南昌大学化学学院,应用化学研究所,江西南昌 330031;上海交通大学化学化工学院,上海 200240;2. 南昌大学化学学院,应用化学研究所,江西南昌 330031
基金项目:国家重点研发计划,国家自然科学基金,江西省科技落地计划,江西省自然科学基金 (20142BAB213013;20151BBE50006). This work was supported by the National Key Research and Development Program,the National Natural Science Foundation of China,the Education Department of Jiangxi Province,the Natural Science Foundation of Jiangxi Province
摘    要:甲醛是室内装修污染的重要组分,已严重危害到人们身体健康,在室温条件下消除甲醛引起了人们的广泛兴趣.目前室温清除甲醛主要有物理吸附法、光催化法、等离子体技术及催化氧化技术.物理吸附法主要采用活性炭等作为吸附剂,其初期吸附效果较好,但当吸附饱和之后会重新释放甲醛造成二次污染;光催化法和等离子体技术需要特殊装置,不适合室内室温环境脱除甲醛;而催化氧化技术则可直接将甲醛转化为无毒无害的水和CO2,因而备受关注.Pt/TiO2被认为是目前消除甲醛最有效的催化剂.为进一步降低贵金属Pt的用量及增强其稳定性(Pt被氧化后其活性会降低),本文首次采用稀土La掺杂锐钛矿型TiO2,负载少量Pt后用于室内低浓度(0.5 ppm)甲醛的催化氧化.活性测试结果表明,纯TiO2催化剂上甲醛转化率在5%以下,有可能是物理吸附或可见光催化所致.负载0.5%Pt后,Pt/TiO2和Pt/La-TiO2甲醛转化率均高于80%,尤其是La掺杂活性高达96%以上,且在连续反应8 h甚至延长至40 h后其活性均未见下降趋势.电镜结果表明,La掺杂Pt/La-TiO2催化剂中Pt粒径从未掺杂的2.2 nm降至1.7 nm;CO程序升温脱附测试表明,Pt/La-TiO2/Pt的分散度达66%,而未掺杂样品仅为51%;X射线光电子能谱测试表明,Pt/La-TiO2的表面氧物种高于Pt/TiO2催化剂,说明La掺杂增强了Pt和载体间的相互作用.为探讨Pt/La-TiO2商业化应用前景,将粉体Pt/La-TiO2涂覆在堇青石蜂窝陶瓷上制备成整体催化剂.该整体催化剂在容积为2 m3的密室测试中5 min内即可将浓度为0.5 ppm的甲醛将至0.02 ppm以下.该催化剂在存放3个月后活性略有下降,但在10 min内仍可将甲醛浓度降至0.08 ppm,达到室内甲醛排放标准.综上,本文成功制备了La掺杂Pt/La-TiO2用于室内低浓度甲醛催化氧化,该催化剂表现出优异的催化性能.通过多种表征手段表明,La修饰后贵金属Pt纳米粒子尺寸减小、分散度提高及Pt与载体间相互作用增强是其活性优异的主要原因.以Pt/La-TiO2粉体制备的整体催化剂同样表现出了高的催化性能,具有工业应用前景.

关 键 词:低浓度甲醛  室温氧化  稀土  镧掺杂    二氧化钛  整体催化剂
收稿时间:2016-08-30

La-doped Pt/TiO2 as an efficient catalyst for room temperature oxidation of low concentration HCHO
Honggen Peng,Jiawei Ying,Jingyan Zhang,Xianhua Zhang,Cheng Peng,Cheng Rao,Wenming Liu,Ning Zhang,Xiang Wang. La-doped Pt/TiO2 as an efficient catalyst for room temperature oxidation of low concentration HCHO[J]. Chinese Journal of Catalysis, 2017, 38(1): 39-47. DOI: 10.1016/S1872-2067(16)62532-9
Authors:Honggen Peng  Jiawei Ying  Jingyan Zhang  Xianhua Zhang  Cheng Peng  Cheng Rao  Wenming Liu  Ning Zhang  Xiang Wang
Affiliation:1. Institute of Applied Chemistry, College of Chemistry, Nanchang University, Nanchang 330031, Jiangxi, China;2. School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
Abstract:Catalytic oxidation of formaldehyde (HCHO) is the most efficient way to purify indoor air of HCHO pollutant. This work investigated rare earth La-doped Pt/TiO2 for low concentration HCHO oxida-tion at room temperature. La-doped Pt/TiO2 had a dramatically promoted catalytic performance for HCHO oxidation. The reasons for the La promotion effect were investigated by N2 adsorption, X-ray diffraction, CO chemisorption, X-ray photoelectron spectroscopy, transmission electron microscopy (TEM) and high-angle annular dark field scanning TEM. The Pt nanoparticle size was reduced to 1.7 nm from 2.2 nm after modification by La, which led to higher Pt dispersion, more exposed active sites and enhanced metal-support interaction. Thus a superior activity for indoor low concentration HCHO oxidation was obtained. Moreover, the La-doped TiO2 can be wash-coated on a cordierite monolith so that very low amounts of Pt (0.01 wt%) can be used. The catalyst was evaluated in a simulated indoor HCHO elimination environment and displayed high purifying efficiency and stabil-ity. It can be potentially used as a commercial catalyst for indoor HCHO elimination.
Keywords:Low-concentration formaldehyde  Room-temperature oxidation  Rare earth  Lanthanum doping  Platinum  Titania  Monolithic catalyst
本文献已被 万方数据 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号