改性粘土预处理垃圾渗滤液中氨氮的吸附热力学和动力学研究

第37卷第1期2018年2月四川环境SICHUANENVIRONMENTVol.37,N〇.1February2018•试验研究•改性粘土预处理垃圾渗滤液中氨氮的吸附热力学和动力学研究吕利\唐艳妮2，姜丽丽3(1.四川省地质工程勘察院，成都610072;2.成都自来水有限责任公司，成都610051;3.西藏金海矿产资源开发有限公司，成都610000)摘要：采用十六烷基三甲基溴化铵（HDTMA)对粘土进行改性，通过X射线衍射、红外光谱、热分析技术对改性粘土进行表征，分析作用机理；并将改性粘土用于垃圾渗滤液中氨氮的处理，对处理过程的吸附热力学和动力学性能进行研究。研究表明：粘土经过改性后，改性粘土的层间间距增大了0.754mn;在303.15K,313.15K,333.15K不同温度下，粘土吸附渗滤液中氨氮的平衡的时间为50min左右，改性后的粘土吸附效果比原土提高了大约2~3倍；改性粘土对氨氮的吸附符合Langmuir■等温吸附模型和Freundlich等温吸附模型；吸附过程标准摩尔吉布斯自由能AG9在-0.1271^/111〇1~-0.0801^/111〇1范围内，标准摩尔焓变厶硭<0，吸附反应过程均属自发的放热过程；吸附动力学数据符合准二级动力学方程和粒子内扩散方程。关键词：改性粘土；垃圾渗滤液；氨氮；热力学；动力学中图分类号:X703文献标识码:A文章编号=1001-3644(2018)01-0022-08StudyonAdsorptionThermodynamicsandKineticsofAmmoniaNitrogeninLandfillLeachatePretreatedbyModifiedClayLVLi1,TANGYan-ni2,JIANGLi-li3(1.SichuanInstituteofGeologicalEngineeringInvestigation,Chengdu610072,China；2.ChengduMunicipalWaterworksCo.,LTD.,Chengdu610051,China；3.TibetJinhaiMineralResourcesDevelopmentCo.,LTD.Chengdu610000,China)Abstract；Inthispaper,HDTMAwasusedtomodifytheclay.Themodifiedclaywascharacterizedbyx-raydiffraction,infraredspectroscopyandthermalanalysis,andthemechanismofactionwasanalyzed.Themodifiedclaywasusedinthetreatmentofammonianitrogeninlandfillleachate,andtheadsorptionthermodynamicsandkineticpropertiesofthetreatmentprocesswerestudied.Theresultsshowthattheinterlayerspacingofmodifiedclayincreasesby0.754nmaftermodification.Atthedifferenttemperaturesof303.15K,313.15K,and333.15K,theequilibriumtimeofammonianitrogeninthelandfillleachateisabout50min,andtheadsorptioneffectofmodifiedclayisabout2~3timeshigherthanthatoftheoriginalsoil.TheadsorptionofammonianitrogenbymodifiedclayaccordswithLangmuirisothermandFreundlichisothermmodel.ThestandardmolarGibbsfreeenergyAG9isintherangeof-0.127kj/mol〜-0.080kj/mol，thestandardmolarenthalpychangeAHe<0,theadsorptionreactionprocessisaspontaneousexothermicprocess.Theadsorptionkineticdataareinaccordancewiththepseudo-secondorderkineticequationandtheparticlediffusionequation.Keywords：Modifiedclay；landfillleachate；ammonianitrog