Sorption Studies Of Methyl Red Dye Removal Using Lemon Grass (Cymbopogon citratus)

Lemongrassleafbasedactivatedcarbon(LGLAC)waspreparedusingphysico-chemicalmethodsformethylred(MR)dyeremovalfromaqueoussolutions.Thesurfacechem-istryofLGLACbeforeadsorptionrevealedthepresenceofdifferentfunctionalgroups:O-H,C-H,C=O,CH3,C=C,N-O,C-OandC-Nwhichwereshiftedaftermethylreddyead-sorption.Brunauer-Emmett-Tellersurfaceandmesoporeareasare836.04m2/gand598.604m2/g,whereas,theaverageporediameterandtotalporevolumeofLGLACare3.62nmand0.472cm3/grespectively.Batchadsorptionwasstudiedusingdifferentparameters:initialdyeconcentrations(25–500mg/L),contacttime(0–24h),solutiontemperature(30–60°C)andsolutionpH(2–12).Adsorptionofmethylreddyewasobservedtoincreasewithincreaseininitialdyeconcentration,contacttimeandsolutiontemperature.Themethylreddyeadsorptionuptakeandpercentageremovalatequilibriumshowedthatthead-sorptionprocessismajorlydependentontheinitialdyeconcentration.Optimumpercent-ageofmethylreddyeremovedwasobservedatpH2.TheadsorptionprocessofmethylreddyeontoLGLACwasendothermicinnature.Thermodynamicparameters,includ-ingentropychange(�S0),enthalpychange(�H0),andGibbsfreeenergychange(�G0)wereevaluated.Theadsorptionprocesswasendothermicandthemechanismfollowedaphysisorptionproces