斜发沸石的改性及吸附机理及其对高氟水的去除

第9卷第7期环境工程学报Vol．9，No．72015年7月ChineseJournalofEnvironmentalEngineeringJul．2015斜发沸石的改性及吸附机理及其对高氟水的去除李尚蛟王银叶马爽肖艳华骆永娜(天津城建大学环境与市政工程学院，天津300384)摘要对斜发沸石不同条件(烘干、焙烧、微波、酸淬、碱淬和盐淬)改性后吸附水中氟离子的性能进行了对比。结果表明，焙烧、酸淬处理沸石较其他改性沸石对F－的吸附效果良好，吸附量分别提高了0．23mg/g和0．44mg/g。进一步研究了焙烧/酸淬沸石对F－的吸附，吸附量达到了0．72mg/g。进而探讨了斜发沸石改性机理。借助BET孔径分析可知，焙烧/酸淬后沸石孔径由原样的22．30nm增大到32．32nm，吸附F－后孔径为19．75nm。焙烧主要是去除沸石孔道中的有机杂质，增大孔道体积和比表面积;而FTIＲ红外光谱分析表明，酸浸渍对Si—O或Al—O键(1581cm－1)的影响较大，产生了新的弯曲振动峰，极大促进了斜发沸石对F－的吸附。F－吸附等温线与Langmuir等温式拟合最佳，斜发沸石对F－的吸附主要为双分子层吸附。关键词斜发沸石焙烧/酸淬氟离子沸石改性吸附模型中图分类号X703．1文献标识码A文章编号1673-9108(2015)07-3288-05ModificationandadsorptionmechanismofclinoptiloliteanditsfluorideremovalfromhighfluoridewaterLiShangjiaoWangYinyeMaShuangXiaoYanhuaLuoYongna(TianjinChengjianUniversity，DepaetmentofEnvironmentalandmunicipalEngineering，Tianjin300384，China)AbstractThecapacitiesofclinoptilolitetoadsorbfluoridefromwastewaterwerecomparedaftermodifica-tionunderdifferentconditionssuchasdrying，roasting，microwavedisposal，pickling，alkalileachingandsaltquenching．Theresultsshowedthattheadsorptioncapacitiesofclinoptilolitedisposedbyroastingandpicklingwerebetterthanthatofclinoptilolitedisposedbyothers，underwhichtheadsorptioncapacitieswereenhancedby0．23mg/gand0．44mg/g，respectively．Furtherstudyindicatedthatthefluorideadsorptioncapacitycouldreach0.72mg/gaftertheclinoptilolitedisposedbyroasting/pickling．Thenthemodificationmechanismsofclinoptilo-litewasexplored．TheBETanalysisshowedthattheaverageporediameterofclinoptiloliteincreasedfrom22．30nmto32．32nmaftermodificationbyroasting/pickling，andturnedto19．75nmaftertheadsorptionoffluoride．Ｒoastingcouldincreasetheporevolumeandthespecificsurfaceareaofclinoptilolitebyremovingtheorganicim-puritiesintheporechannels．Moreover，theFTIＲanalysisshowedthatpicklinghadagreatinfluenceonSi—OorAl—Obond(1581cm－1)withnewbendingvibrationpeaks，whichgreatlypromotedthecapacityofclinoptilo-litetoadsorbfluoride．TheadsorptionmodelwasmainlydoublemoleculelayerwithadsorptionisothermfittingbestwiththeFreundlichisotherm．Keywordsclin