过渡金属改性的ZSM-5催化剂应用于甲硫醚转化制甲硫醇.pdf

物理化学学报( Wuli Huaxue Xuebao
1148
Acta Phys.-Chim.Sin.2014,30(6),1148-1154
June
Article
doi:10.3866/PKU.WHXB20140418
www.whxb.pku.edu.cn
过渡金属改性的ZSM5催化剂应用于甲硫醚转化制甲硫醇
陈世萍1王伟明刘迎伟2魏育才2袁成龙1方维平1杨意泉
厦门大学化学化工学院化学工程与生物工程系,福建厦门361005;2厦门大学化学化工学院化学系,福建厦门361005)
摘要:负载过渡金属的ZSM-5催化剂用于催化甲硫醚(DMS)转化成甲硫醇(MT)的反应.实验结果表明,催化
剂的甲硫醚转化率提高和甲硫醇选择性降低的趋勢一样,都是以下顺序:Co/ZSM-5>Mo/ZSM-5> Ni/ZSM-5>
WZSM-5.表征结果表明,由于过渡金属阳离子(Wr、NIP、Co2、Mo°)比AP活泼,而改性过程中We、NP'、Co3
Mo“分别代替了部分APr,使得改性催化剂对DMS和MT的化学吸附作用更强.过渡金属的引入使得ZSM-5总
酸度增强,提高了C-S键的裂解能力,从而改进了催化转化DMS的能力.研究结果发现,在转化DMS的过程
中,金属活性位和酸性位之间通过强的协同效应起作用
关键词:ZSM-5;过渡金属;甲硫醚;甲硫醇
中图分类号:O643
Transition Metal Promoted ZSM-5 Catalysts for the Conversion of
Dimethyl Sulfide into Methanethio
CHEN Shi-ping WANG Wei-ming lu Ying-wei WEI Yu-cai YUAN Cheng-long
FANG Wei-ping YANG Yi-quan i
Department of Chemical and Biochemical Engineering College of Chemist and Chemical Engineering, Xiamen niversit
Xiamen 361005 Fwan Province, P R China; Department of Chemistry, College ofchemistry and Chem ersity,
Engineering, Xiamen University, Xiamen 361005, Fujian Province, P R. China
Abstract: Zsm-5-supported transition metal catalysts were prepared and used to catalyze the conversion
dimethylsullde(DMS)intomethanethiol(MT).Testresultsindicatedthattheactitiesofthecatalystsfor
the conversion of MS increase as ollow: OZSM-5M/ZSM-5>i/ZSM-5>W/ZSM-5.The decrease in
MT selectivity followed the same trend. The characterization results showed that transition metal cations
(W N Co M replaced some A sies din o more active in chemisorption of DMS and MT
since transition metal cations are more active than Al The incorporation of transition metals into ZSM-5
enhances the total acidity of ZSM-5 and increases its capacity to rupture C-S bonds. This subsequently
improves its catalytic behavior in the conversion of DMS. We found that the metal active sites and closely
situated acidic sites have a strong synergistic effect when converting DMS
Key Words: ZSM-5, Transition metal; Dimethyl sulfide Methanethiol
1 Introduction
for methionine, the production of MT becomes more impor-
containing compounds such as dimethyl sulfide tant. Industrially, it is synthesized from methanol and hydro-
(DMS) methanethiol(MT) and HS are referred to as total re. gen sulfide over alumina-supported metal oxide catalysts; and
duced sulfur(TRS) compounds, and they all have malodorous DMS, a major byproduct, is always formed along with meth
odor. Among them, MT is now used as an important chemical anethol. In the Has atmosphere, DMS can be converted into
intermediate to produce organosulfur compounds such as me- MT in the presence of a catalyst, so as to boost the yield of
thionine, widely used as feed additive with increasing demand methanethiol and lower the content of DMS in wastewater
Received: February 26, 2014; Revised: April 17, 2014; Published on Web: April 18, 201 4
Correspondingauthor.Emailyiquan(@xmu.edu.cn;Tel:+86-592-2186368;Fax:+86-592-2186368
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