Page 187 - 《精细化工》2020年第6期
P. 187
第 37 卷第 6 期 精 细 化 工 Vol.37, No.6
202 0 年 6 月 FINE CHEMICALS June 2020
水处理技术与环境保护
Co/Fe 类水滑石活化过硫酸钠降解苯酚特性
程爱华,张燕妮
(西安科技大学 地质与环境学院,陕西 西安 710054)
摘要:采用共沉淀法制备 Co/Fe 类水滑石(Co/Fe-LDHs),焙烧后得到焙烧态 Co/Fe 类水滑石(Co/Fe-LDO)。
通过 XRD、SEM、BET 和 XPS 对样品的晶体结构及表面形貌进行表征。考察了其活化过硫酸钠(PS)降解苯
2
酚的影响因素及机理。结果表明,焙烧可使 Co/Fe-LDHs 形成复合金属氧化物 Co/Fe-LDO。比表面积从 41.2 m /g
3
3
2
增大至 56.8 m /g,孔体积从 0.2 cm /g 增大至 0.3 cm /g,增强了样品对过 PS 活化性能。在反应时间 30 min、反
应温度 25.0 ℃、PS 投加量为 0.2 g/L、Co/Fe-LDO 投加量为 0.2 g/L、溶液 pH 6.0、苯酚初始质量浓度 100.0 mg/L
−
时,苯酚降解率可达 90.1%。机理分析表明,SO 4 •和•OH 在 Co/Fe-LDO 活化 PS 降解苯酚反应过程中起主要作用。
关键词:类水滑石;钴;铁;活化;过硫酸钠;苯酚;水处理技术
中图分类号:TB332;X703. 1 文献标识码:A 文章编号:1003-5214 (2020) 06-1253-06
Degradation of phenol by Co/Fe layered double hydroxides
activated sodium persulfate
CHENG Aihua, ZHANG Yanni
(School of Geology and Environment, Xi’an University of Science and Technology, Xi'an 710054, Shaanxi, China)
Abstract: Co/Fe layered double hydroxides (Co/Fe-LDHs) was prepared by coprecipitation method and
then calcined to form Co/Fe layered double hydroxides (Co/Fe-LDO). The crystalline structure and
morphology of the samples were characterized by XRD, SEM, BET and XPS. The influencing factors and
mechanism of phenol degradation by Co/Fe-LDHs or Co/Fe-LDO activated sodium persulfate (PS) were
investigated. The results showed that calcination made Co/Fe-LDHs transform mixed metal oxides
2
2
Co/Fe-LDO. After calcination, the specific surface area of the sample increased from 41.2 m /g to 56.8 m /g,
3
3
and the pore volume increased from 0.2 cm /g to 0.3 cm /g. In addition, the activation ability of Co/Fe-LDO
to PS was higher than that of Co/Fe-LDHs. Under the conditions of reaction time 30 min, reaction
temperature 25.0 ℃, dosage of PS 0.2 g/L, dosage of Co/Fe-LDO 0.2 g/L, pH of solution 6.0, and initial
phenol mass concentration 100.0 mg/L, the degradation rate of phenol reached 90.1%. The mechanism
−
analysis revealed that SO 4 • and •OH played an important role in the process of phenol degradation by
CO/Fe LDO activated PS.
Key words: layered double hydroxides; cobalt; iron; activation; sodium persulfate; phenol; water treatment
technology
[1]
含酚废水属于典型的有毒且难降解的工业废水 , AOPs 越来越受到重视,但过硫酸盐在自然条件下对
[6]
[2]
严重威胁人类健康 。基于羟基自由基(•OH)的高 苯酚的降解速率较低,需要采用热活化 [4-5] 、光活化 、
−
[3]
[7]
[8]
级氧化技术 (AOPs)处理含酚废水等难降解有机 活性炭活化 和过渡金属离子活化 等产生 SO 4 •,
废水是目前关注的热点,但由于 H 2 O 2 的腐蚀性和 使污染物降解为 CO 2 、H 2 O。其中,过渡金属离子
O 3 的不稳定性,在一定程度上限制了•OH 的应用。 活化可以在常温、常压下快速进行,不需要额外能
−
过硫酸盐获取便利、性能稳定,使得基于 SO 4 •的 量,因而被广泛应用。
收稿日期:2019-12-12; 定用日期:2020-02-17; DOI: 10.13550/j.jxhg.20191163
基金项目:国家自然科学基金项目(51278418)
作者简介:程爱华(1977—),女,博士,副教授,E-mail:cah_cheng@126.com。