24小时热门版块排行榜

返回列表

当前主题已经存档。

当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖

雁过无痕

至尊木虫 (职业作家)

资深木虫

应助: 47 (小学生)
金币: 11111.6
散金: 4500
红花: 22
帖子: 4427
在线: 1219.6小时
虫号: 219403
注册: 2006-03-13
性别: GG
专业: 波谱分析与成像分析

[交流] 如何转化丙酮为环氧丙烷

丙酮吸附在催化剂,有部分转化为环氧丙烷
但是不知道什么催化剂表面容易实现这个转化,比如酸性(B酸or L酸,强度),碱性，氧化还原性，形貌等等
由于一个人涉猎有限，所以请大家提供信息，是否有文献提及这一问题，详细的模糊的都可以
谢谢

回复此楼

» 猜你喜欢

双非本硕光催化方向想读博，请各位老师看看我！已经有2人回复
瑞典林雪平大学范立洲课题组现招聘博士后、岗位制博士生已经有0人回复
专业论文润色/翻译怎么收费? 已经有287人回复
中国科大仿生界面材料科学全国重点实验室戴懿涛研究员/江雷院士团队招聘科研助理已经有0人回复
中国科大仿生界面材料科学全国重点实验室戴懿涛研究员/江雷院士团队招聘科研助理已经有0人回复
寻求物理化学学报最新的投稿模板！已经有4人回复
东南大学杰青/海优团队招聘催化方向博士后已经有866人回复
投稿咨询已经有7人回复
自科面上散金币祈福已经有61人回复
铁钼催化剂成型已经有2人回复
求问：LATP煅烧应该使用什么容器？已经有0人回复

2026年招收硕士2名（可调剂），博士1名。招收药物固态化学教学科研人员（博士后或特聘副教授）各一名。

1楼 2007-09-12 11:47:41

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

chenwei19828888

木虫 (正式写手)

应助: 12 (小学生)
金币: 3667.1
红花: 2
帖子: 991
在线: 124.5小时
虫号: 272462
注册: 2006-08-19
性别: GG
专业: 电化学分析

★
buffaloli(金币+1,VIP+0):多谢应助了！
buffaloli(金币+0,VIP+0):帮你把abstract加上了。

钛硅介孔材料在双氧水,或有机过氧化物做为氧化剂的条件下,对环氧化物的选择性很高
  例如,J Porous Mater  2006  13  81-89

M. Ramakrishna Prasad1 , G. Madhavi1, A. Ramachander Rao1, S. J. Kulkarni1  and K. V. Raghavan1

(1)  Indian Institute of Chemical Technology, Hyderabad, 500 007, India

Received: 24 December 2003  Revised: 8 August 2005

Abstract  A series of titanium rich isomorphous substituted Ti MCM-41 and HMS materials have been synthesized with different Si/Ti ratios. The highest amount of Ti incorporated in synthesis gel is in TiMCM-41 (Si/Ti = 10). Whereas for TiHMS catalysts, Ti is incorporated up to Si/Ti = 50 successfully without forming any extra framework TiO2. Cyclohexene epoxidation reaction with dry tert-butyl hydroperoxide (TBHP) as an oxidant has been studied to evaluate the catalytic properties of Ti substituted mesoporous catalysts. The effect of molar ratio of substrate

xidant in this reaction has been studied and high conversion, high selectivity were achieved at 2: 1 molar ratio with TiMCM-41 (Si/Ti =25). Dry TBHP (in dichloromethane) and chloroform were found as good oxidant and solvent system for this reaction. Pure siliceous mesoporous silica and low `Ti' substituted mesoporous silicas were found to be efficient catalysts for oxidation of cyclohexene. An interesting variation of the selectivity from allylic oxidation to epoxidation during oxidation of cyclohexene was observed with an increase in the Ti amount in the mesoporous framework. The allylic oxidation of cyclohexene has been carried out using molecular oxygen as an oxidant and in the presence of a small amount of TBHP as initiator. Siliceous HMS materials gave better conversion compared to MCM-41 type of materials and other conventional silicas like silica gel, fumed silica etc. in allylic oxidation of cyclohexene. Epoxidation of higher cyclic olefins like cyclooctene, cyclododecene, cis-cyclododecene and linear olefins 1-Heptene, cis-2-hexene, 1-undecene was carried out over TiMCM-41 (Si/Ti = 25). Ti substituted mesoporous catalysts were characterized by elemental analysis, XRD, FTIR, UVDRS, 29SiMASNMR, BET surface area and pore size distribution techniques.
Keywords TiMCM-41 - TiHMS - Epoxidation - Allylic oxidation - TBHP and molecular oxygen

[ Last edited by buffaloli on 2007-12-3 at 12:56 ]