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1、ETHYLp-HYDROXYBENZOATEPreparedatthe51stJECFA(1998),publishedinFNP52Add6(1998)supersedingspecificationspreparedatthe44thJECFA(1995),publishedinFNP52Add3(1995).GroupADI0-10mg/kgbwforethyl,methylandpropylp-hydroxybenzoate,establishedatthe17thJECFAin1973.SYNONYMSEthylpar
2、aben,ethylp-oxybenzoate,INSNo.214DEFINITIONChemicalnamesEthylp-hydroxybenzoate,ethylesterofp-hydroxybenzoicacidC.A.S.number120-47-8ChemicalformulaC9H10O3StructuralformulaFormulaweight166.18AssayNotlessthan99.0%onthedriedbasisDESCRIPTIONAlmostodourless,small,colourles
3、scrystalsorawhite,crystallinepowderFUNCTIONALUSESPreservativeCHARACTERISTICSIDENTIFICATIONSolubility(Vol.4)Freelysolubleinethanol,etherandpropyleneglycol.Meltingrange(Vol.4)115-118ºTestforp-hydroxybenzoateMeltingrangeofp-hydroxybenzoicacidderivedfromthesampleis212-o2
4、17To0.5gofthesampleadd10mlofsodiumhydroxideTS.Boilfor30minandconcentratetoabout5ml.Cool,acidifywithdilutesulfuricacidTS,collecttheprecipitateonafilter,andwashthoroughlywithwater.Dryinadesiccatoroversulfuricacid.Determinethemeltingrangeofp-hydroxybenzoicacidsoobtained
5、.PURITYLossondrying(Vol.4)Notmorethan0.5%(80º,2h)Sulfatedash(Vol.4)Notmorethan0.05%Test2gofthesample(MethodI)AcidityHeat750mgofthesamplewith15mlofwaterat80ofor1min,cool,andfilter.Thefiltrateshouldbeacidorneutraltolitmus.To10mlofthefiltrateadd0.2mlof0.1Nsodiumhydroxid
6、eand2dropsofmethylredTS.Thesolutionshouldbeyellowwithoutevenalightcastofpink.p-HydroxybenzoicacidandDissolve0.5gofthesample,accuratelyweighed,in30mlofether,addsalicylicacid20mlofa1in100sodiumhydrogencarbonatesolution,shake,andseparatethewaterlayer.Washthewaterlayerwi
7、thtwo20mlportionsofether,add5mlofdilutesulfuricacidand30mlofether,andshake.Separatetheetherlayer,andshakewithabout10mlofwater.Filtertheetherlayer,andwashthevesselandthefilterwithasmallamountofether.Combinethewashingsandthefiltrate,evaporateetheronawaterbath,anddrythe
8、residueoversulfuricacidtoconstantweight.Theweightoftheresidueshouldnotexceed5mg.Dissolveanyresiduein25mlofowater,heattoabout70,filt