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I硅藻土与腐殖土的炭化处理及吸附特性研究摘要硅藻土是远古时期硅藻类植物的遗骸，主要成分是非晶态蛋白石，在其表面沉积附着着大量的天然有机物。这些成分复杂的有机物在适当的处理条件下，可发生炭化反应，在多孔的硅藻土表面原位附着一层炭化膜，改变原来的SiO2的表面性质及吸附性能。但一直以来这方面的研究还非常有限。腐殖土作为植物的残骸，其中所含的有机物与硅藻土中的有机质有着一定的相似之处，因此可以对腐殖土进行类似处理，来对硅藻土的炭化进行对照研究。利用硅藻土表面沉积的有机质原位合成炭化膜，主要是控制反应过程中O2的参与，因此可以考虑不使用惰性气体保护焙烧法、碳热还原法及水热炭化法等。考虑到现有的实验条件，选择以碳热还原法为主，水热炭化法为辅，研究硅藻土有机质的炭化过程，以及由此产生的影响。本论文分别以国产的低品位高烧失内蒙硅藻土及市售腐殖土为原料，采用碳热还原法及水热炭化法进行炭化处理，在材料表面制成具有一定吸附能力的活性炭膜。研究炭化条件（包括温度和pH）对炭化效果的影响。通过X射线衍射仪、差热-热重分析等技术手段对炭化后的硅藻土、腐殖土进行元素组成、矿物相、热性能、形貌分析表征。实验结果表明：在600-1000℃区间内，缺氧煅烧的硅藻土烧失量及对亚甲基蓝的吸附性能随温度的升高而逐渐降低。同样条件下，腐殖土在800℃的烧失量最高并且吸附性最好。经过参考资料及对实验结果的分析，可以初步确定硅藻土的最佳炭化条件为缺氧600℃。水热炭化实验中，在给定的范围内，pH越高、反应时间越短、离子强度越大，炭化硅藻土的吸附效果越好。因此，最佳水热炭化条件为180℃水热24h、pH=10、有NaCl。关键词：硅藻土；腐殖土；炭化处理；水热炭化；吸附性能IIDiatomiteandhumussoilcarbonizedprocessinganditsresidueofadsorptionperformanceAbstractDiatomiteistheremainsofancienttimesdiatomplants,andits’maincomponentisamorphoussilica,andplentyofnaturalorganicmatterattachtothesurface.Thesecomplicatedcomponentoforganicmattercantakethecarbonationreactioninproperprocessingcondition.Attachalayerofcarbonationmembraneonthesurfaceofporousdiatomite,changethesurfacepropertiesandadsorptionproperties.Buttheresearchofthisaspectisstillverylimited.Asplantdebris,theorganicmatterinhumussoilhasacertainsimilarityofthatindiatomite.So,wecandothesimilartreatmentbetweenhumussoilanddiatomitetodotheresearchofdiatomite’scarbonizedprocessinganditsresidueofadsorption.In-situsynthesiscarbonationmembranebyusingthesurfacedepositionalorganicmatterofdiatomite,mainlycontroltheoxygen’sparticipationduringtheprocessofreaction.Sowecanconsidertousethemethodofroastingundertheprotectionofinertgas,CarbothermicReductionmethodandhydrothermalcarbonizationmethod.Consideringtheexistingexperimentalconditions,thechoiceisgivenprioritytoCarbothermicReductionmethod,andgivenauxiliarytohydrothermalcarbonizationmethod.studythecarbonationprocessoforganicmatteronthesurfaceofdiatomiteandtheresultingeffects.ThispaperonthebasisoftheNeimonggollow-gradediatomiteandhumussoilforrawmaterial,usingtheCarbothermicReductionmethodandhydrothermalcarbonizationmethodtoitscarbonized,manufacturetheactivatedcarbonwithadsorptionproperties.Researchcarbonizedconditions(includethetemperatureandpHandionintensity)totheinfluenceofcarbon.ByX-raydiffraction,differentialthermalanalyzerandthermogravimetricanalyzertothediatomitecarbonizationcomposition,mineralphasesforelements,thermalproperties,morphologycharacterized.Theexperimentalresultsshowthat:in600-1000℃range,oxygencalcineddiatomiteignitionlossandadsorptionpropertiesofmethylenebluewasgraduallyIIIdecreasedwiththeriseoftemperature.Hydrothermalcarbonizationexperiment,withinthescopeofthegivenconditions,thehigherthepH,shorterreactiontime,ionstrength,thegreatertheincomeofthecarbonizeddiatomiteadsorptioneffectisbetter.Therefore,optimumhydrothermalcarbonizationconditionsforthepH=10,24hwithNaCl.Keywords：diatomite;humussoil;carbonization;Hydrothermalcarbonization;adsorptionperformance目录摘要...........................................................................................................IAbstract.....................................................................................................II目录...........................................................................................................4第1章绪论.............................................................................................11.1硅藻土概述................................................................................11.3活性炭的性质............................................................................41.4活性炭的制备方法....................................................................41.5硅藻土的炭化方法.....................................................................71.6研究意义与内容........................................................................7第2章实验部分.....................................................................................92.1原土处理与表征........................................................................92.2实验方法..................................................................................122.3实验仪器及药品......................................................................152.4分析表征仪器及方法..............................................................16第3章结果与讨论...............................................................................173.1炭热还原法的炭化效果..........................................................173.2水热炭化法的炭化效果..........................................................223.3样品对亚甲基蓝的吸附效果..................................................30第4章结论.........................................................................................32参考文献........................................................................................XXXIII致谢.........................................................................错误!未定义书签。英文翻译........................................................................................XXXIII中文翻译...................................................................错误!未定义书签。第1章绪论1第1章绪论1.1硅藻土概