分子篮上CO2吸附的红外研究聚乙烯亚胺改性介孔分子筛吸附剂

IF 2.781
S. Overbury, Xiaoxing Wang, Jason C. Clark, Xiaoliang Ma, Xiaochun Xu, C. Song, V. Schwartz
{"title":"分子篮上CO2吸附的红外研究聚乙烯亚胺改性介孔分子筛吸附剂","authors":"S. Overbury, Xiaoxing Wang, Jason C. Clark, Xiaoliang Ma, Xiaochun Xu, C. Song, V. Schwartz","doi":"10.1021/JP809946Y","DOIUrl":null,"url":null,"abstract":"An infrared study has been conducted on CO{sub 2} sorption into nanoporous CO{sub 2} 'molecular basket' sorbents prepared by loading polyethylenimine (PEI) into mesoporous molecular sieve SBA-15. IR results from DRIFTS showed that a part of loaded PEI is anchored on the surface of SBA-15 through the interaction between amine groups and isolated surface silanol groups. Raising the temperature from 25 to 75 C increased the molecular flexibility of PEI loaded in the mesopore channels, which may partly contribute to the increase of CO{sub 2} sorption capacity at higher temperatures. CO{sub 2} sorption/desorption behavior studied by in situ transmission FTIR showed that CO{sub 2} is sorbed on amine sites through the formation of alkylammonium carbamates and absorbed into the multiple layers of PEI located in mesopores of SBA-15. A new observation by in situ IR is that two broad IR bands emerged at 2450 and 2160 cm{sup -1} with CO{sub 2} flowing over PEI(50)/SBA-15, which could be attributed to chemically sorbed CO{sub 2} species on PEI molecules inside the mesopores of SBA-15. The intensities of these two bands also increased with increasing CO{sub 2} exposure time and with raising CO{sub 2} sorption temperature. By comparison of the CO{sub 2} sorptionmore » rate at 25 and 75 C in terms of differential IR intensities, it was found that CO{sub 2} sorption over molecular basket sorbent includes two rate regimes which suggest two distinct steps: rapid sorption on exposed outer surface layers of PEI (controlled by sorption affinity or thermodynamics) and the diffusion and sorption inside the bulk of multiple layers of PEI (controlled by diffusion). The sorption of CO{sub 2} is reversible at 75 C. Comparative IR examination of the CO{sub 2} sorption/desorption spectra on dry and prewetted PEI/SBA-15 sorbent revealed that presorbed water does not significantly affect the CO{sub 2}-amine interaction patterns.« less","PeriodicalId":58,"journal":{"name":"The Journal of Physical Chemistry ","volume":"126 1","pages":""},"PeriodicalIF":2.7810,"publicationDate":"2009-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"339","resultStr":"{\"title\":\"Infrared Study of CO2 Sorption over ?Molecular Basket? Sorbent Consisting of Polyethylenimine-Modified Mesoporous Molecular Sieve\",\"authors\":\"S. Overbury, Xiaoxing Wang, Jason C. Clark, Xiaoliang Ma, Xiaochun Xu, C. Song, V. Schwartz\",\"doi\":\"10.1021/JP809946Y\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"An infrared study has been conducted on CO{sub 2} sorption into nanoporous CO{sub 2} 'molecular basket' sorbents prepared by loading polyethylenimine (PEI) into mesoporous molecular sieve SBA-15. IR results from DRIFTS showed that a part of loaded PEI is anchored on the surface of SBA-15 through the interaction between amine groups and isolated surface silanol groups. Raising the temperature from 25 to 75 C increased the molecular flexibility of PEI loaded in the mesopore channels, which may partly contribute to the increase of CO{sub 2} sorption capacity at higher temperatures. CO{sub 2} sorption/desorption behavior studied by in situ transmission FTIR showed that CO{sub 2} is sorbed on amine sites through the formation of alkylammonium carbamates and absorbed into the multiple layers of PEI located in mesopores of SBA-15. A new observation by in situ IR is that two broad IR bands emerged at 2450 and 2160 cm{sup -1} with CO{sub 2} flowing over PEI(50)/SBA-15, which could be attributed to chemically sorbed CO{sub 2} species on PEI molecules inside the mesopores of SBA-15. The intensities of these two bands also increased with increasing CO{sub 2} exposure time and with raising CO{sub 2} sorption temperature. By comparison of the CO{sub 2} sorptionmore » rate at 25 and 75 C in terms of differential IR intensities, it was found that CO{sub 2} sorption over molecular basket sorbent includes two rate regimes which suggest two distinct steps: rapid sorption on exposed outer surface layers of PEI (controlled by sorption affinity or thermodynamics) and the diffusion and sorption inside the bulk of multiple layers of PEI (controlled by diffusion). The sorption of CO{sub 2} is reversible at 75 C. Comparative IR examination of the CO{sub 2} sorption/desorption spectra on dry and prewetted PEI/SBA-15 sorbent revealed that presorbed water does not significantly affect the CO{sub 2}-amine interaction patterns.« less\",\"PeriodicalId\":58,\"journal\":{\"name\":\"The Journal of Physical Chemistry \",\"volume\":\"126 1\",\"pages\":\"\"},\"PeriodicalIF\":2.7810,\"publicationDate\":\"2009-04-02\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"339\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"The Journal of Physical Chemistry \",\"FirstCategoryId\":\"1\",\"ListUrlMain\":\"https://doi.org/10.1021/JP809946Y\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Journal of Physical Chemistry ","FirstCategoryId":"1","ListUrlMain":"https://doi.org/10.1021/JP809946Y","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 339

摘要

以介孔分子筛SBA-15为载体,负载聚乙烯亚胺(PEI)制备纳米多孔CO{sub 2}“分子筐”吸附剂,对其吸附CO{sub 2}进行了红外研究。DRIFTS的红外光谱结果表明,负载PEI的一部分通过胺基与分离的表面硅烷醇基之间的相互作用被锚定在SBA-15表面。温度从25℃升高到75℃时,负载在介孔通道中的PEI的分子柔韧性增加,这可能是在较高温度下CO{sub 2}吸附能力增加的部分原因。原位透射FTIR对CO{sub 2}的吸附/解吸行为研究表明,CO{sub 2}通过氨基甲酸烷基铵的形成被吸附在胺位点上,并被吸附到位于SBA-15介孔的多层PEI中。原位红外观察发现,CO{sub 2}在PEI(50)/SBA-15上流动时,在2450和2160 cm{sup -1}处出现了两个较宽的IR波段,这可能是由于在SBA-15介孔内PEI分子上化学吸附了CO{sub 2}。随着CO{sub 2}暴露时间的延长和CO{sub 2}吸附温度的升高,这两个谱带的强度也随之增加。通过比较25℃和75℃时CO{sub 2}的吸附速率,发现CO{sub 2}在分子篮吸附剂上的吸附包括两种速率体系,这表明了两个不同的步骤:在PEI暴露的外表层上的快速吸附(由吸附亲和性或热力学控制)和在多层PEI内部的扩散和吸附(由扩散控制)。在75℃时,CO{sub 2}的吸附是可逆的。通过对干燥和预湿的PEI/SBA-15吸附剂CO{sub 2}的吸附/解吸光谱的比较红外分析表明,预湿的水对CO{sub 2}-胺的相互作用模式没有显著影响。«少
本文章由计算机程序翻译,如有差异,请以英文原文为准。
Infrared Study of CO2 Sorption over ?Molecular Basket? Sorbent Consisting of Polyethylenimine-Modified Mesoporous Molecular Sieve
An infrared study has been conducted on CO{sub 2} sorption into nanoporous CO{sub 2} 'molecular basket' sorbents prepared by loading polyethylenimine (PEI) into mesoporous molecular sieve SBA-15. IR results from DRIFTS showed that a part of loaded PEI is anchored on the surface of SBA-15 through the interaction between amine groups and isolated surface silanol groups. Raising the temperature from 25 to 75 C increased the molecular flexibility of PEI loaded in the mesopore channels, which may partly contribute to the increase of CO{sub 2} sorption capacity at higher temperatures. CO{sub 2} sorption/desorption behavior studied by in situ transmission FTIR showed that CO{sub 2} is sorbed on amine sites through the formation of alkylammonium carbamates and absorbed into the multiple layers of PEI located in mesopores of SBA-15. A new observation by in situ IR is that two broad IR bands emerged at 2450 and 2160 cm{sup -1} with CO{sub 2} flowing over PEI(50)/SBA-15, which could be attributed to chemically sorbed CO{sub 2} species on PEI molecules inside the mesopores of SBA-15. The intensities of these two bands also increased with increasing CO{sub 2} exposure time and with raising CO{sub 2} sorption temperature. By comparison of the CO{sub 2} sorptionmore » rate at 25 and 75 C in terms of differential IR intensities, it was found that CO{sub 2} sorption over molecular basket sorbent includes two rate regimes which suggest two distinct steps: rapid sorption on exposed outer surface layers of PEI (controlled by sorption affinity or thermodynamics) and the diffusion and sorption inside the bulk of multiple layers of PEI (controlled by diffusion). The sorption of CO{sub 2} is reversible at 75 C. Comparative IR examination of the CO{sub 2} sorption/desorption spectra on dry and prewetted PEI/SBA-15 sorbent revealed that presorbed water does not significantly affect the CO{sub 2}-amine interaction patterns.« less
求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
自引率
0.00%
发文量
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信