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1 Availabl onlin at wwwplagiarsarchlibrarycom Dr Chmica Sinica, 2014, 5(4):25-29 ISSN: CODEN (USA) CSHIA5 Adsorption charactristics of mangans (II) on granular activatd carbon Yogita K Mshram 1, N T Khati 2 and R U Khop 1 1 Dpartmnt of Chmistry, S S E S Amt s Scinc Collg, Congrss Nagar, Nagpur(MS), India 2 Dpartmnt of Chmistry, Priyadarshini Collg of Enginring, Hingna Nagpur(MS), India ABSTRACT In th prsnt invstigation th surfac of granular activatd carbon was modifid by organic ligand for rmoval of Mn 2+ ions from aquous solution Exprimnt was carrid out in batch mod at constant tmpratur of C Som radily availabl drivativs of bnzn wr usd for surfac modification of GAC To nhanc th capacity to adsorb mangans GACs wr loadd with organic ligand Th quilibrium adsorption data was bttr fittd to th Langmuir and Frundlich adsorption modl Study was also xtndd to valuat th surfac ara occupid by mangans in th formation of monolayr on GAC Kywords: Adsorption, Mn (II), Granular Activatd Carbon(GAC), 3-Nitrophthalic Acid (3-NPTA), Filtrasorb100 (F-100), Filtrasorb 816 (F-816) INTRODUCTION In prsnt day contxt watr pollution is th biggst hazard for all forms of lif Th nvironmntal pollution has bn th most rmarkabl sid ffct of rapid industrialization and growing population of th world Today, almost all th things, which ar most ncssary to th human bings, ar mor or lss contaminatd by toxic substancs Mangans is common contaminant in ground watr, as a divalnt ion Mn 2+ and it is considrd a pollutant mainly bcaus of its organolptic proprtis Th World Halth Organization (WHO) has st a guidlin valu 5 mg/l of mangans in drinking watr [1] Watr gts pollutd by mangans ions coming from many industris mainly pyrulusit MnO 2 tratmnt, stl alloy, dry cll battris, glass and cramic, paint and varnish, ink and dys, match and firworks A substantial part of watr usd for potabl us shows contamination significantly xcding th maximum contaminant lvl Thus it is an important and ncssary for th rsarchrs to dvlop appropriat mthods to chck th dtrioration of th nvironmnt Numbrs of mthods hav bn dvlopd by th workrs for th rmoval of havy mtals lik ion xchang, solvnt xtraction, chmical prcipitation, biological opration, filtration tc [2-8] But adsorption of havy mtals by activatd carbon and modifid activatd carbon provd to b th most conomically viabl tchniqu in this application[9-19] In prsnt study adsorption isothrms wr stablishd and th rsults modld by th Langmuir and Frundlich isothrm MATERIALS AND METHODS All th chmicals usd in xprimnt wr analytical ragnt grad Th mangans solution was prpard by dissolving rquisit MnSO 4 (E-Mrck) in frshly prpard distilld watr In prsnt study granular activatd carbons namly F-816 and F-100 supplid by Calgon Carbon Corporation Ltd Pittusbrg PA USA wr usd as adsorbnt Each grad of carbons was first subjctd to siz fractionation to obtain a particls of dsird siz using a siv shakr (M/s Jayant Tst Sivr Mumbai) and th particls rtaind in btwn 840ụ-1400ụ wr usd in all xprimnt Ths particls wr washd svral tims with boild distilld watr until clar lchat was obtaind 25

2 and collctd in ptridish Finally th sampls wr drid in an ovn at a tmpratur of C, coold at room tmpratur and stord in dsiccators until us A tn solutions of known concntration of Mn 2+ ions wr prpard from main stock solution by diluting with distilld watr Potassium priodat mthod was usd to form th complx with Mn 2+ ions[20] Thn absorbanc of ach solution was masurd spctrophotomtrically at 525 nm of wavlnght using Chmito-spctoscan UV 2700, Doubl bam UV-Vis SpctrophotomtrTh Br s law calibration curv was stablishd by plotting th graph btwn absorbanc vrsus concntration In th prsnt work 3-Nitrophthalic acid was slctd as organic ligand to modify th surfac of GAC It was first purifid and rcrystallizd by standard mthod Th xprimntal mlting point of 3-Nitropthalic acid (2185 C) compard with litratur valu (219 C) [21]For dtrmining adsorption isothrm, 05 gm of th drid GAC was takn in ach clan shaking bottl and 200 ml of acid solution of a spcific concntration was shakn for 5 hrs using rmi stirrr at about 500 rpm Th solution was thn filtrd off and th carbon was washd svral tim thoroughly with distilld watr This carbon was transfrrd to shaking bottl and thn 200 ml Mn 2+ ion solution of P H =5 was addd to it Th mixtur was thn stirrd for 5 hrs at constant tmpratur of 25 ±1 C Th initial and final concntration of th Mn 2+ ion in mg /L was thn stimatd using mathmatical quation obtaind from calibration curv Th batch adsorption xprimnts wr rpatd to nsur rproducibl rsult RESULTS AND DISCUSSION Adsorption isothrms ar ssntial for th dscription of how mtal ion concntration intract with carbon surfac and also usful to optimiz th us of granular activatd carbon as a adsorbnt for th rmoval of mangans Adsorption of Mn 2+ ions on ligand loadd GAC was studid by batch tchniqu Th uptak of of Mn 2+ on th loadd GAC was calculatd from quation q ( C C ) = 0 V W Whr, q = Concntration of Mn 2+ on th ligand loadd GAC in mg/mmol of ligand at quilibrium, C o = Initial concntration of Mn 2+ in solution in mg/l, C = Equilibrium concntration of Mn 2+ in solution in mg/l, V = Volum of solution in Lit, W = Wight of th carbon Th adsorption isothrms of ligand loadd GAC obtaind by plotting q and C ar shown in Fig-1and Fig-2 q mg/mmol C mg/l Fig-1 Adsorption Isothrm Systm: F-816-3NPTA-Mn 2+ q mg/mmol C mg/l Fig-2 Adsorption Isothrm Systm: F-100-3NPTA-Mn 2+ Adsorption isothrm: Th adsorption quilibrium data wr fittd to th Langmuir and Frundlich isothrm Th most important Langmuir modl of monolayr adsorption of mangans ions on th surfac of carbon sits is xprssd in th linar form As pr Langmuir thory, th non linar quation can b rprsntd by 26

3 q = C Q 0 b 1 + bc Th linarisd form of Langmuir isothrm can b xprssd as = q bq C Q Whr, Q 0 =(monolayr adsorption capacity) amount adsorbd pr unit wight of th carbon forming a complx monolayr on th adsorbnt surfac, b = Langmuir constant A plot of 1/C vrsus 1/q found to b linar indicating th applicability of Langmuir modl Th Frundlich modl is an mpirical quation dscribs th htrognous surfacs and multilayr adsorption and is xprssd in non linar form as q = k C 1 n It may b linarisd as 1 logq = log Kf + logc n Whr th constant K f and 1/n of th Frundlich modl rlatd to th adsorption capacity and adsorption intnsity rspctivly,which dpnds on th htrognity of th matrial A plot of log q vrsus log C was fairly showing validity of Frundlich quation ovr a rang of concntration Th slop of 1/n ranging btwn 0and 1 is a masur of th surfac htrognity, bcoming mor htrognous as its valu gts closr to zro Fig-3 to Fig- 6 illustrat th plot of Langmuir and Frundlich isothrm for F NPTA-Mn 2+ and F NPTA-Mn 2+ Th valu of K f, 1/n, b, q max and Q for F NPTA-Mn 2+ and F NPTA-Mn 2+ ar shown in Tabl No1 F NPTA-Mn 2+ systms show th supriority ovr F NPTA-Mn 2+ for th adsorption procss 1/q /C 1/q /C Fig-3Langmuir Adsorption Isothrm Systm:GAC-F NPTA-Mn 2+ Fig-4 Langmuir Adsorption Isothrm Systm:GAC-F NPTA-Mn 2+ Th saturation of monolayr by adsorbat gav th valu of q was usd for dtrmination of surfac ara of th adsorbnt For this purpos a plot of 1/q vrsus 1/C hlpd in dtrmination of 1/Q o and hnc Q o Th surfac ara of th carbon through Mn 2+ adsorption can thn b rprsntd as S =N Q o A Whr, S =Surfac ara of adsorbnt cm 2 /g N =Avogadro numbr A =Cross sction ara of th adsorbat molcul 27

4 logq logc - logc logq Fig-5 Frundlich Adsorption Isothrm Systm:GAC-F NPTA-Mn 2+ Fig-6 Frundlich Adsorption Isothrm Systm:GAC-F NPTA-Mn 2+ Thus it is possibl to dtrmin th surfac ara of ligand loadd GAC at th saturation lvl whn a monolayr of th Mn 2+ would covr ntir surfac of GAC adsorbnt Th dtrmination of surfac ara occupid by a singl Mn 2+ ion, wr calculatd using th xprssion givn by Bruanaur and Emmt A =4 66 [M/ 4N a d] 2/3 Whr, M=Atomic wight of Mangans [22] N = Avogadro numbr d = Dnsity of Mangans (73 gm/cm 3 ) [23] Th valus of S obtaind from Q o and S obtaind from q max ar fairly comparabl and ar rportd in th Tabl-2 Tabl-1 Langmuir and Frundlich Isothrm Constants SrNo Systm Langmuir Constant Frundlich Constant qmax(mg/mmol) Q 0 b 1/n Kf 1 GAC-F NPTA-Mn GAC-F NPTA -Mn Th numrical valu of K f and 1/n for GAC F-816 ar and rspctivly Th fractional valu of 1/n indicats that th surfac of GAC is of th htrognous typ with an xponntial distribution of nrgy sit Th highr numrical valu of K f confirms th significant affinity of Mn 2+ ions for granular activatd carbon Th valu of Frundlich and Langmuir constants indicat th supriority of GAC F-816 ovr GAC-F-100, in th rmoval of Mn 2+ from aquous phas Tabl No-2 Surfac Ara of GACs Sr No Systm Ara S S 1 GAC-F NPTA-Mn cm cm 2 /g cm 2 /g 2 GAC-F NPTA-Mn cm cm 2 /g cm 2 /g CONCLUSION In th prsnt invstigation, it is concludd that GACs ar uniqu adsorbnts for th rmoval of mangans ions from aquous phas Th adsorptiv ability of F-816 is highr than F-100 This is du to th fact that activatd carbon hav high surfac ara and high microporous charactrs Th rsults indicat th GAC is an ffctiv adsorbnt for th rmoval of Mn(II) ions from aquous solution undr th tstd xprimntal condition and could b usful in th tratmnt procss of industrial wasts or th analytical application 28

5 Acknowldgmnt Th authors ar thankful to th Principal, Priyadarshini Collg of Enginring, Hingna, Nagpur and th Principal, Scinc Collg Congrss Nagar, Nagpur for providing laboratory facilitis to carry out th xprimntal work REFERENCES [1] WHO Guidlins for Drinking Watr Quality World Halth Organization, Grmany 2003 [2] Komwska E, Lach J, Kacpzak M, Nza E Dsalination,2007,206, [3] Knock WR, Clvngr T, Ghosh MM, Novak JT, Proc 33rd Purdu Industrial wast conf,1978, 33, [4] McDonald CW, Bajwa RS, Sp Sci,1977, [5] Bhattachayya D, Jumawan A, Sun G, Schwitzbl K, Prcipitation of sulphid: AICHE symposium sris, 1980 Watr 77, [6] Linstdt KD, Houck CP, O Connor JT, J Watr Pollut Control Fd,1971, 43, [7] Chang SY, Huang JC, Liu YC, (1984 Summr National AICHE mting, Philadlphia PA,1984, [8] D Mora SJ, Harrison RM, Watr Rs, 1983, 17, [9] Youssf AM, El-wakil AM, El-Sharkawy WA, Farag AB, Toggan KH, Adsorpt Sci Tchnol,1996, 13, [10] Youssf AM, El-Nabarawy Th, Samra SE, Colloids and surfacs, 2004, 235, [11] Youssf AM, El-Khouly S, El-Nabarawy Carbon Ltt,2008, 9, 8-17 [12] Alaya MN, Youssf AM, Karman M, Abdl-Al H, carbon Sci, 2006, 7, 9-18 [13] Alaya MN, Youssf AM, Karman M, Abdl-Al H carbon Sci,2006, 7: 9-18 [14] Ht YV, Ghols SBand Khop RU, Dr chmica Sinica,2012, 3(4): [15] Gawand NJ,Choudhari AR and Khop RU, Advancs in applid scinc Rsarch,2012,3 (3): [16] Komwska E, Lach J, Kacpzak M, Nza E Dsalination, 2007, 206, [17] Mna, AK, Mishra, GK, Rai, PK, Rajagopal, C, Nagar PN, Journal of Hazardous Matrials, 2005, 122 (1 2), [18] Ht Y V, Ghols SBand Khop RU, Journal of Matrials Scinc and Enginring, 2011,1, [19] Gunjat JK, Ghols SBand Khop RU, Dr chmica Sinica, 2014, 5(3),5-9 [20] Vogl,AI;Quantitativ Inorganic Analysis,4 th Edn Longman Group LtdEngland,pp, 1978, pp [21] Furniss BS, Hannaford AJ, Smithn Ptr WG,Tatchll AR, Vogl s Txtbook of practical organic chmistry (5 th dition), pp 1348,Parson publication [22] Vogl Txtbook of Quantitativ Analysis, 5 th Edn ELBS with Longman Group, 1989, pp819 [23] Handbook of fin chmicals (Aldrich Chmistry) pp No