碳酸二甲酯作甲基化試劑合成甲基苯甲醚的研究.pdf

1、分類號密級Y842889單位代碼學(xué)號寧夏大學(xué)學(xué)位論文碳酸二甲酯作甲基化試劑合成甲基苯甲醚的研究f07490202089Studyonthecatalyticsynthesisofmethoxytolueneusingdimethylcarbonateasmethylatingreagents研究生姓名：篚逃指導(dǎo)教師：趙云生數(shù)援合作指導(dǎo)教師：匿送拯副熬握申請學(xué)位類別：蘭堂亟專業(yè)領(lǐng)域名稱：王些催絲研究方向：與王迸業(yè)堂晶僉盛所在學(xué)院：寶夏篚遺

2、絲王重壺塞墜室絲堂絲至堂醫(yī)2005年3月30日主塞當(dāng)蘭絲!：壘：篁蘭!!竺：：!AbstractThecatalyticsynthesisofmethoxytolueneviathereactionofcresolwithdimethylcarbonate(DMC)asmethylatingreagentundervaporsolidphaseconditionswasstudiedThermodynamiccalculationsde

3、monstratedthatthegaseousreactionofo—cresolwithDMCwasendothermicandhightemperaturewasfavoredThetheoreticconversionofcresolreached100％astemperaturewasuDto400KThecatalyticactivitiesofactivecarbon(AC)loadedwithalkalimetalsal

4、tsbyvacuumimpregnationwerestudiedKOH／AC(10wt％)showedthehighestactivityA98％conversionofP—cresolwitha996％selectivityofPmethoxytoluenewasachievedatthereactionconditions：temperature548K，pressure11MPa，GHSV1845h～，n(DMC)／n(pcre

5、s01)I5：1AlthoughKOH／ACexhibitedtheexcellentcatalyticactivityforthemethylationattheexperimentalconditions，itwasfoundtodeactivatequicklyafterabout8hreactionsThepossiblereasonwasrelatedtosignificantreductioninsurfaceareaand

6、porevolumeofthecatalystasindicatedbycharacterizationresultsUsingNaYloadedwithKOAc(2mmol／g)byvacuumimpregnationandmicrowaveradiationtreatmenLaocresolconversionof83％witha997％selectivityofo—methoxytoluenewasobtainedattheopt

7、imizedreactionconditions：temperature548K，pressure06MPaGHSV870h～，n(DMC)／n(pcres01)，1BothvacuumimpregnationandmicrowaveradiationtreatmentimprovedthedispersionofKOAconthesurfaceofNaYandthecatalystsshowedgoodthermalstability

8、between450600K私indicatedbyXRDandTGDTAcharacterizationUndertheoptimumconditionstheactivityofthecatalystwasstablewithin30hreactionCharacterizationresults(XRD、SEM、C02一TPDandN2absorption)suggestedthatsurfacesofthecatalystsaf

9、terthetestswerecoveredbycarbondepositionfromDMCdecompositionathightemperatureandporesofthecatalystwerejammed；whichcausedtheactivitylostThecomparativeinvestigationforthesynthesisofmethoxytoluene(o一、m一、F)overKOAc／NaYcataly

10、stattheoptimizedconditionsshowedthatasimilarreactionbehaviorwithconversionsofcresolsallhigherthan76％andselectivitiesofmethoxytolueneabove99％ItisalsodemonstratedthatDMCisamuchmoreefficieatmethylatingagentthanmethanolforth