资源描述:
《颗粒膨润土的有机改性及其吸附水中2,4-二氯酚柱试验研究》由会员上传分享,免费在线阅读,更多相关内容在学术论文-天天文库。
1、ADissertationSubmittedinPartialFulfillmentoftheRequirementsfortheDegreeofMasterinEngineeringStudyontheorganicmodificationofgranularbentoniteanditsadsorptionof2,4-dichlorophenolfromaqueoussolutionbycolumntestMasterCandidate:QinXiongMajor:EnvironmentalEngin
2、eeringSupervisor:Prof.LiuHongWuhanUniversityofScienceandTechnologyWuhan,Hubei430081,P.R.ChinaMay,2015摘要以粉末膨润土为原料制备出颗粒状膨润土,以有机表面活性剂-十六烷基三甲基溴化铵(CTMAB)为改性剂,分别用常规湿法改性和微波改性两种方法制得有机颗粒膨润土,以2,4-二氯酚(2,4-DCP)为目标污染物,考察了不同条件下,两种改性颗粒膨润土对2,4-DCP的去除效果,选择了快速简便、效果好的微波法,并通
3、过控制微波时间使改性与干燥一步完成。采用SEM、FTIR、XRD等手段表征了颗粒膨润土煅烧前后与改性前后在形貌、结构及性能方面的变化,探讨了吸附机理。柱试验考察了不同2,4-DCP浓度、水力负荷和CTMAB用量时有机颗粒膨润土填充柱的穿透时间和吸附容量。此外,评价了有机颗粒膨润土的再生性能。研究结果表明,与常规改性2h相比,微波一步法改性6min后制得的有机颗粒膨润土对2,4-DCP的吸附率高16.7%;改性后,有机改性剂CTMAB进入到了膨润土的层间,使膨润土片层变小且更加分散,层间距由0.92nm增大
4、为1.01nm,并且,CTMAB改善了膨润土的疏水性,对2,4-DCP有分配作用,因而颗粒膨润土的吸附效率较改性前增大了42.6%;以100%的膨润土阳离子交换容量改性后,有机颗粒膨润土对30mg/L的2,4-DCP柱吸附饱和容量达到了11.76mg/g,吸附柱的穿透时间为220min。当再生温度为550℃时,再生效果好,但吸附容量下降为9.38mg/g,再生3次后,吸附性能仍能达到再生一次的97.2%。关键词:颗粒膨润土;改性;吸附;2,4-二氯酚;十六烷基三甲基溴化铵IAbstractGranular
5、bentonitewaspreparedusingbentonitepowderasrawmaterialandmodifiedwithcetyltrimethylammoniumbromide(CTMAB)byconventionalwetmethodandmicrowavemethodtosynthetizegranularorganobentonite.Theadsorptioncapabilityofgranularorganobentonitemodifiedbytwomethodwasinve
6、stigatedusing2,4-dichlorphenol(2,4-DCP)astargetcontaminantunderdifferentconditions.Themicrowavemodificationwasselectedasitisfaster,moreconvenientandeffectivecomparedwithconventionalwetmodification,andthemodifyinganddryingcanbecompletedinonestepbycontrolli
7、ngmicrowavetime.SEM,FTIRandXRDwereusedtoanalysethemorphology,structureandpropertiesofgranularbentonitebeforeandaftermodified,andtheadsorptionmechanismwasdiscussed.Thecolumntestsunderdifferentconcentrationsof2,4-DCP,hydraulicloadingsanddosesofCTMABwerecond
8、uctedtoinvestigatethebreakthroughtimeandadsorptioncapacityofgranularorganobentonitecolumn.Furthermore,theregenerationperformanceofgranularorganobentonitewasevaluated.Theresultsshowedthatthegranularorganobentonitemod