欢迎来到天天文库
浏览记录
ID:37118059
大小:344.63 KB
页数:5页
时间:2019-05-18
《煅烧凹凸棒石的水化处理对其结构演化和吸附NH3的影响》由会员上传分享,免费在线阅读,更多相关内容在行业资料-天天文库。
1、第39卷第11期硅酸盐学报VO1.39,NO.112011年l1月J0URNALOFTHECHINESECERAMICS0CIETYNovember,2011煅烧凹凸棒石的水化处理对其结构演化和吸附NH3的影响孔德军,陈天虎,刘海波,陈冬,谢晶晶,庆承松(合肥工业大学资源与环境工程学院,合肥230009)摘要:采用x射线衍射分析了煅烧凹凸棒石的水化处理对其结构演化的影响;通过NH3吸附试验表征煅烧凹凸棒石水化处理后表面性质的变化,揭示了凹凸棒石对NH的吸附机理。结果表明:随着煅烧温度的不断提高,凹凸棒石中的结晶水和结构水逐步脱除,内孔道结构发生折叠塌陷,凹凸棒石
2、的内孔道折叠温度在250~300℃之间,只有低于300℃煅烧的凹凸棒石经过水化处理折叠的内孔道才能恢复。凹凸棒石经过200~300℃煅烧再水化处理,对NH3的吸附量比未处理的凹凸棒石显著增加,尤其是250℃煅烧的凹凸棒石经水化处理后对NH3的吸附量增加了75%,250℃是煅烧凹凸棒石水化处理吸附NH,的最佳温度点。低于300℃煅烧的凹凸棒石水化处理恢复了部分结晶水,推测NH3与这部分结晶水发生了氢键作用,凹凸棒石对NH,的吸附既有外表面吸附,又有内孔道吸附。关键词:凹凸棒石;煅烧;水化;结构演化;氨吸附中图分类号:TB321文献标志码:A文章编号:O454r-5
3、648(2Ol1)l1—1867~)5网络出版时间:201l一10—2510:49:06DOI:CNKI:11-2310/TQ.201l1025.1049,026网络出版地址:http://www.cnki.net/kcms/detail/11.2310.TQ.20111025.1049.026.htmlEfectofRehydrationO11StructureEvolutionandAmmoniaAdsorptionofCalcinedPalygorskiteKONGDejun,CHEN~anhu,LIUHaibo,CHENDong,XIEJingfing,
4、QINGChengsong(SchoolofNaturalResourcesandEnvironmentEngineering,HefeiUniversityofTechnology,Hefei230009,China)Abstract:ThestructureevolutionofcalcinedpalygorskiteduringrehydrationwasanalyzedbyX-raydiffraction.EflfectOfrehydra—tiononthesurfaceprope~iesofcalcinedpalygorskitewasinvestig
5、atedviatheexperimentsofammoniaadsorption,andthecorre-spondingmechanismofNHadsorptionwasdiscussed.Theresultsshowthatthecrystallizationwaterandstructura1waterinpaly—gorskiteiSremovedgraduallyandtheporestructureOCCurSfoldingandcollapsewhenthecalcinationtemperatureincreases.Thestructureo
6、fpalygorskitewasfoldedbetween250and300℃.andthefoldingwasreversiblebefore300℃.Comparedtoarawpaly-gorskite。therehydrationpromotedtheNHadsorptiononpalygorskitewhenthecalciningtemperatureiSbetween200℃and300℃SincetheamountofNH3adsorptionincreasedby75%at250℃,thetemperature(250℃)iSthusregar
7、dedastheoptimumtempera—tureforNHadsorption.Therehydrationcouldrecoverpartsofthecrystalwaterinpalygorskitewhenthecalciningtemperatureisbelow300℃.andthereactionofadsorptionammoniainrehydratedpalygorskitewasconferredthroughtheformationofH—bondswiththecoordinatedwater.NH1couldbeadsorbedo
8、ntheexterna1
此文档下载收益归作者所有