Cs改性Au/TS-1低温丙烯气相环氧化性能研究
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- 英文论文题名：Better performance for gas-phase epoxidation of propylene at lower temperature by Cs modified of Au/TS-1 catalyst
- 论文作者：李智姗 ; 马卫华
- 英文论文作者：Li Zhishan ; Ma Weihua ; School of Chemical Engineering ; Nanjing University of Science and Technology
- 年：2016
- 作者机构：南京理工大学化工学院;
- 论文关键词：钛硅分子筛 ; 铯改性 ; 负载纳米金 ; 丙烯气相环氧化 ; 低温催化性能
- 会议召开时间：2016-07-01
- 会议录名称：中国化学会第30届学术年会摘要集-第三十七分会：纳米催化
- 语种：中文
- 分类号：O643.36
- 学会代码：ZGHY
- 会议名称：中国化学会第30届学术年会-第三十七分会 ; 纳米催化
- 会议地点：中国辽宁大连
- 主办单位：中国化学会
- 学会名称：中国化学会
- 页数：1
- 文件大小：129k
- 原文格式：D
- 会议级别：全国
摘要
采用水热合成法制备平均粒径在210 nm的钛硅分子筛(TS-1)载体,再以碳酸铯(Cs2CO3)为沉积沉淀剂制得Cs改性的TS-1负载纳米金催化剂(记为Au/TS-1 Cs),用于丙烯气相环氧化反应。通过研究Au/TS-1 Cs在高温(200℃)和低温(164℃)下的催化性能,结果表明:在低温条件下,该催化剂的环氧丙烷生成速率(PO rate)更加平稳,环氧丙烷选择性(PO selectivity)和氢气利用率(H2 efficiency)均有大幅度提高,丙烯转化率(C3H6conversion)变化不大。根据透射电子显微镜(TEM)、傅里叶红外光谱(FTIR)、热重分析(TGA)及氨气程序升温吸脱附(NH3-TPD),可知低温较高温具有更优的催化性能主要是由Au粒径的变化引起的,而催化剂表面的积碳程度和表面酸性的积累并不是造成性能差异的主要原因。故反应温度为164℃可能更适合Au/TS-1 Cs作用于丙烯气相环氧化催化体系。
The titanium silicalite-1(TS-1) support was synthesized by the hydrothermal synthesis and nano-gold(Au) with Cs_2CO_3 as precipitating agent was deposited by the deposition precipitation method to obtain the Cs modified catalyst,denoted as Au/TS-1 Cs,which was used for gas-phase epoxidation of propylene.Comparing performances of Au/TS-1 Cs at 200 ℃ with 164 ℃,results show that propylene oxide(PO) rate of the latter was ~ 300g_(po)h~(-1) kg_(cat)~(-1) and more stable than that of the former.Both PO selectivity and hydrogen efficiency of the latter had been improved significantly than that of the former.Characterization results suggest that the changes of Au particle size is the main cause of different performances,and the degree of carbon deposits on catalyst surface as well as the accumulation of surface acidity have no great effect.Therefore,better performance for propylene epoxidation of Au/TS-1 Cs was achieved at 164 ℃.
The titanium silicalite-1(TS-1) support was synthesized by the hydrothermal synthesis and nano-gold(Au) with Cs_2CO_3 as precipitating agent was deposited by the deposition precipitation method to obtain the Cs modified catalyst,denoted as Au/TS-1 Cs,which was used for gas-phase epoxidation of propylene.Comparing performances of Au/TS-1 Cs at 200 ℃ with 164 ℃,results show that propylene oxide(PO) rate of the latter was ~ 300g_(po)h~(-1) kg_(cat)~(-1) and more stable than that of the former.Both PO selectivity and hydrogen efficiency of the latter had been improved significantly than that of the former.Characterization results suggest that the changes of Au particle size is the main cause of different performances,and the degree of carbon deposits on catalyst surface as well as the accumulation of surface acidity have no great effect.Therefore,better performance for propylene epoxidation of Au/TS-1 Cs was achieved at 164 ℃.
引文
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[2]Lee W.S.;Akatay M.C.;Stach E.A.;Ribeiro F.H.;Delgass W.N.J.Catalysis,2013,308:98-113.
[3]Qi C.,J.Huang,Bao S.,Su H.,Akita T.,Haruta M.J.Catalysis,2011,281:12-20
[2]Lee W.S.;Akatay M.C.;Stach E.A.;Ribeiro F.H.;Delgass W.N.J.Catalysis,2013,308:98-113.
[3]Qi C.,J.Huang,Bao S.,Su H.,Akita T.,Haruta M.J.Catalysis,2011,281:12-20