Modified Poly (Styrene Maleic Anhydride) Copolymer for the Removal of Toxic Metal Cations from Aqueous Solutions

Transcription

1 Amrican Journal of Polymr Scinc 2015, 5(3): DOI: /j.ajps Modifid Poly (Styrn Malic Anhydrid) Copolymr for th Rmoval of Toxic Mtal Cations from Aquous Solutions Eman Abo-Bakr 2, Said S. Elkholy 1, Mahr Z. Elsab 1,* 1 Dpartmnt of Chmistry, Faculty of scinc, Cairo Univrsity, Egypt 2 Polymrs and Pigmnts Dpt., National Rsarch Cntr, Dokki, Cairo, Egypt Abstract Poly (styrn-malic anhydrid) (SMA) copolymr was modifid by racting th anhydrid group with two diamins drivativs. Th modifid copolymrs wr charactrizd by spctral, thrmal and X-ray analyss. Th obtaind product was usd for Cd (II), Cu (II) and Pb (II) uptak from aquous solutions. Th absorption procss was followd using atomic absorption spctromtry. Th ffcts of svral xprimntal paramtrs such as ph, concntration and adsorption tim on th xtnt of cations absorption wr studid. Th quilibrium rmoval prformanc of th copolymr is analyzd according to th Langmuir and Frundlich adsorption isothrm modl that shows rsult fittd to both modls. Som kintic modls wr applid to fit th absorption mchanism. Kywords Styrn malic anhydrid copolymr, Diamin, Adsorption isothrms, Mtal uptak 1. Introduction Contamination of aquous nvironmnts by havy mtals and dys is a worldwid nvironmntal problm bcaus ths substancs ar not biodgradabl and ar highly toxic to living organisms. Toxic mtals such as Cu, Cd, and Pb hav bcom an co-toxicological hazard of prim intrst and incrasing significanc owing to thir tndncy to accumulat in th vital organs in humans, animals and accumulation through th food chain [1 3]. Coppr pollution ariss from coppr mining and smlting, brass manufactur, lctroplating industris and xcssiv us of Cu-basd agri-chmicals. Coppr along with arsnic and mrcury, is rcognizd as th highst rlativ mammalian toxic [4] and continud inhalation of coppr containing sprays is linkd with an incras in lung cancr among xposd workrs [5]. Cadmium is introducd into watr bodis from smlting, mtal plating, cadmium nickl battris, phosphat frtilizrs, mining, pigmnts, stabilizrs, alloy industris and swag sludg. Th harmful ffcts of cadmium includ numbr of acut and chronic disordrs such as itai itai disas, rnal damag, mphysma, hyprtnsion and tsticular atrophy [6]. Lad is nurotoxic and childrn ar particularly vulnrabl bcaus of th rapidly dvloping nrvous systm. Lad is known to inhibit th activity of thr * Corrsponding author: mzlsab@yahoo.com (Mahr Z. Elsab) Publishd onlin at Copyright 2015 Scintific & Acadmic Publishing. All Rights Rsrvd critical nzyms (5-aminolavulinat dhyratas (ALA-D), coproporphyrinogn oxidas (COPRO-O) and frrochlatas (FERRO-C)) critical in hm synthsis, causing abnormal concntrations of hm prcursors in blood and urin [7]. Lad (Pb) is dischargd into th nvironmnt from automobil xhausts, industrial sourcs. In th soil, Pb is convrtd to forms unavailabl to plants. Any lad that is absorbd by plants tnds to rmain in th roots and is not transportd to th shoots [7]. Hnc, rmoval of coppr, cadmium and lad from watr and wastwatr assums importanc. Thr ar svral mthods to trat th mtal contaminatd fflunt such as prcipitation, ion xchang and adsorption, tc. [8, 9]. Among all th approachs proposd, adsorption is on of th most popular mthods and is currntly considrd as an ffctiv, fficint and conomic mthod for wastwatr purification [10,11]. Prsntly low cost adsorbnts ar bcoming th focus of many invstigations on th rmoval of havy mtals from aquous solutions. Rmoval of coppr and cadmium from th aquous solutions was also achivd by activatd carbon. In this rgard, synthsis of nw adsorbnts from a varity of low-cost synthtic polymrs using chlat-forming polymric ligands is notworthy [11, 12]. Styrn-malic anhydrid copolymr (SMA) is a wll-known commrcializd polymr [13] that has attractd spcial attntion du to th advantag of its convnint prparation [14] and solubility of alkali salt in watr, as wll as it is a spaghtti-shapd linar polymr with varying lngths (that is to say that th distribution of rlativ

2 56 Eman Abo-Bakr t al.: Modifid Poly (Styrn Malic Anhydrid) Copolymr for th Rmoval of Toxic Mtal Cations from Aquous Solutions molcular mass can b adjustd) [15]. Th prsnc of malic anhydrid (MA) moity along its backbon structur improvs its absorption capacity spcially aftr th hydrolysis of th malic anhydrid moity into carboxylic acid group with incrasing hydrophilicity of th polymr [16]. Th copolymrization of MA with vinyl monomrs and thir subsqunt hydrolysis hav also ld to copolymrs xhibiting rmarkabl slctivity toward divalnt mtal-ion uptak [17-19]. In this work, w rval a nw ractiv copolymr that has bn prpard by th modification of SMA copolymr by diamins. Th prsnc of carboxylic groups in th sam polymr with diamin groups should provid th polymr with th high hydrophilicity rquird for th fast kintics of mtal uptak. 2. Exprimntal 2.1. Matrials Ethyln diamin and hxamthyln diamin ar products of Aldrich. Styrn/malic anhydrid (SMA-40 XIRAN ), (Molcular Wight Mw, 6094 g/mol and Rsin Molcular Wight, Mn 3500 g/mol GPC) wr kindly supplid by Polyscop Polymrs Company, Nthrlands. Ttrahydrofuran (THF), thanol and dithyl thr from th local markt wr usd as rcivd Prparation of SMA-Diamin Drivativ A solution of SMA in (THF) was addd to diamin drivativs. A twofold xcss of diamins to SMA was mployd to avoid th possibl cross linking sid raction btwn th SMA and diamins [19, 20]. A molar ratio of th anhydrid unit, diamin drivativs of 1:2 was usd. Th mixtur was stirrd for 6 h, and finally prcipitatd into (THF) followd by th rmoval of THF. Th prcipitat was washd with thanol svral tims and r-prcipitatd in dithyl thr. Th products obtaind ar Styrn malic anhydrid thyln diamin SMA-EthDA and Styrn malic anhydrid hxamthyln diamin SMA-HmDA. Schm 1 dscribs th prparation procss. Schm 1. SMA and diamin drivativ 2.3. Charactrizations FTIR infrard masurmnt was obtaind using a Prkin Elmr 398 FTIR spctrophotomtr btwn 400 and 4000 cm -1. Thrmogravimtric analysis TGA studis wr prformd on a Shimadzu TGA-50H instrumnt. Th sampls wr hatd at a rat of 10 C/min in nitrogn atmosphr ph Study of Adsorption onto th Modifid SMA Copolymr Th xprimnts prformd to dtrmin th ffct of ph on Cd (II), Cu (II) and Pb (II) adsorption wr carrid out by placing 0.1 g of th dry copolymr in sris of flasks containing 20 ml 500 mg/l mtal ion solution. Th dsird ph was adjustd using 0.1M HCl and 0.1M NaOH. Th flasks wr shakn for 24 h at 25 C. Aftr adsorption, th filtrat of ach flask was analyzd for th mtal ion concntration by Atomic Absorption Spctromtr Adsorption Kintics Coppr (II), cadmium (II) and lad (II) solutions with th dsird concntration (1000 mg/l) wr prpard from coppr (II) chlorid anhydrat, cadmium chlorid and lad chlorid in dionizd watr. Approximatly (0.05) g of tstd copolymr wr addd to a 20 ml of stock solution. Th flasks wr sald and shakn at 150 rpm in a constant tmpratur shakr at 25 C, and wr thn takn out at a dsird tim intrval. Finally, th concntration of coppr, cadmium and lad in ach solution wr dtrmind using a Varian Spctr AA 220FS atomic adsorption spctromtr. Th adsorbd amounts of coppr, cadmium and lad pr wight of sampls at tim t, q t = (mg.g -1 ), wr calculatd from th mass balanc quation as [21] ( Co Ct) V qt = (1) m Whr Co (mg.l -1 ) and Ct (mg.l -1 ) rprsnt th initial and th concntrations of Cu, Cd and Pb at a givn tim t (min), rspctivly, V (ml) is th volum of th solution and m (g) is th wight of modifid SMA polymr in th flask Adsorption Isothrms 0.1 g dry copolymr was placd in a flask thn 20 ml of mtal ion solution at a givn concntration was addd, and th ph valu was rcordd. Th flasks wr shakn at 150 rpm for 24 h whil kping th tmpratur at 25 C. Th concntration of th solution was dtrmind by Atomic Adsorption spctromtr and th mtal ion uptak q (maximum amount adsorbd) was calculatd using th following quation: v q ( ) = Co C (2) m 2.7. X-ray Diffraction X-ray diffraction analysis (XRD) was carrid out by a Scintag powdr diffractomtr. Th X-ray diffraction pattrns wr dtrmind in powdry sampls with Ni-filtrd CuKα at 40 kv and 40mA wr rcordd from angls of in 2θ.

3 Amrican Journal of Polymr Scinc 2015, 5(3): Rsults and Discussion 3.1. Charactrization Elmntal Analysis Th lmntal analysis rsults of copolymrs ar shown in Tabl (1). Th nitrogn contnt (7-9%) in** th two modifid copolymrs rvals that th raction btwn SMA and diamin drivativs has occurrd. Tabl 1. Elmntal analysis data for SMA and SMA di-amin drivativs Composition C% H% N% SMA Th pak intnsity at 2870 cm 1 (CH 3 strtch) and 2930 cm 1 (CH 2 strtch) bcom strongr du to th thyln and hxamthyln diamin contribution. Th absorption pak at 1600 cm 1 may b attributd to th carbonyl group of th amid-acid Thrmogravimtric Analysis Th thrmal proprtis of th SMA copolymr and its two synthsizd drivativs hav bn assistd by Thrmogravimtric analysis. Figur. 2 illustrats th thrmal bhavior of th thr copolymrs whn hatd undr nitrogn atmosphr with a hating rat of 10 C/min. SMA- EthDA SMA- HmDA Infrard Spctra Analysis FTIR spctroscopy has bn usd for th charactrization of th SMA copolymr and th modifid SMA copolymr As shown in Figur. (1) th prsnc of som hydrolyzd carboxylic groups which can b idntifid by th prsnc of a broad pronouncd band at around 3443 cm -1. Th band at 2940 cm -1 is du to th C-H strtching in th backbon of th SMA copolymr. Th prominnt absorption bands in th rangs of and cm -1 ar assignd to th asymmtrical and symmtrical strtching vibration of C=O groups of th malic anhydrid moitis in th copolymr, rspctivly. Th absorptions at cm 1 and cm 1 indicat th prsnc of aromatic ring. Aftr th raction, a dcras in th intnsity of th MA absorption with th apparanc of nw pak at 1500 cm 1 was obsrvd. In th fingrprint rgion, th pak at cm 1 is attributd to th strtching of th graftd diamin. Figur 2. Thrmal analysis of SMA and drivativs Figur 1. (a) SMA, (b) SMA-EthDA, (c) SMA-HmDA Th chmical structur of th SMA backbon is significantly changd, that is, th 5-mmbrd anhydrid ring is convrtd ithr into (a) an str carboxylic acid, (b) an str, or (c) an imid [22]. Ths diffrnt chmical structurs may lad to diffrnt thrmos-stabilitis. Figur. 2 displays th thrmal bhaviour of th pristin copolymr and its drivativs. Th TGA rval that th two amino drivativs ar slightly mor thrmally stabl. Figur 2b shows th first drivativs of TGA tracs of SMA and SMA modifid sampls. As sn from th figur SMA40 copolymr dcomposs in a singl stp at 358 C, whil th modifid sampls xhibit two dcomposition bands. For th SMA-EthDA th first dcomposition stp at 170 C can b attributd to th limination of th thyln amin sid chain. Th main dcomposition occurs at 395 C rsulting from

4 58 Eman Abo-Bakr t al.: Modifid Poly (Styrn Malic Anhydrid) Copolymr for th Rmoval of Toxic Mtal Cations from Aquous Solutions dcomposition of th polymr backbon, which is 37 C highr than that of SMA. Th first dcomposition stp for th SMA- HmDA is at 207 C. Th main dcomposition occurs at 81 C highr than that of SMA at 439 C. This bhaviour indicats that th modifid copolymrs xhibit bttr thrmostability than that of th original SMA copolymr ph Effct on th Mtal Ion Adsorption It can b sn from Figur 3 that th uptak of mtal ions incrass as th ph incrass to rach a maximum valu at around ph 4.0, 6.0 and 3.0 for Cu (II), Cd (II) and Pb (II), rspctivly. Th numbr of activ sits on th surfac of th adsorbnt may chang with varying th ph. This could b xplaind by th fact that at low ph (acidic solution), th amin groups in th modifid SMA ar mostly protonatd which induc an lctrostatic rpulsion of th mtal ions [23, 24]. So, th protonation of amin groups in acidic solutions maks th polymr bhavs as a cationic idntity and consquntly th potntial for attracting mtal anions dcrass [25]. Thrfor, comptition xistd btwn protons and mtal ions for adsorption sits and consquntly th adsorption capacity dcrasd. At highr ph valus (basic solution), prcipitation of mtal hydroxid occurs simultanously with th adsorption of mtal ions, thrfor, ph of maximum adsorption for ach mtal ions was chosn for furthr studis. Th raction kintic paramtrs for th adsorption procss wr studid by batch mthod. Th psudo-first-ordr [26, 27], psudo-scond-ordr [28, 29] and intraparticl diffusion [30] kintic modls wr slctd to lucidat th adsorption kintic procss in this work. Figur 4. Effct of adsorption tim on th uptak of Cd (II), Cu (II), and Pb (II) on th modifid SMA Figur 3. Effct of ph on th adsorption of Cu (II), Cd (II) and Pb (II) on modifid SMA 3.3. Adsorption Kintics From Figur 4, it can b sn that th ffct of contact tim on th adsorption of Cu (II) suggstd that th coppr adsorption is highr for th SMA-HmDA drivativ than that of th SMA-EthDA drivativ, which may point to an activ participation of NH 2 in th procss of adsorption. On th othr hand, th adsorption of Cd and Pb is highr on SMA-EthDA and it taks a longr tim to rach th quilibrium for ths mtal ion on both drivativs. Figur 5. Psudo-first-ordr kintic plots for (a) SMA-EthDA and (b) SMA-HmDA Th Lagrgrn psudo-first-ordr kintic modl is rprsntd as [31, 32]:

5 Amrican Journal of Polymr Scinc 2015, 5(3): k1 log( q qt ) = log q ( ) Whr k 1 is th psudo-first-ordr rat constant (min 1 ) of adsorption, q and q t (mg/g) ar th amounts of mtal ion adsorbd at quilibrium and at tim t (min), rspctivly. Th q and rat constant k 1 wr calculatd by plotting th log (q - q t ) vrsus t. Th plots for psudo-first-ordr modl ar prsntd in Figur. (5). Figur 6. Psudo-scond-ordr kintic plots for a) SMA-EthDA and (b) SMA-HmDA Th psudo-scond ordr modl can b writtn as [21]: t (3) t q t 1 = k q ( ) t q Whr k 2 is th psudo-scond-ordr rat constant of adsorption (g mg -1 min 1 ). Th kintic paramtrs for psudo-scond-ordr modl ar dtrmind from th linar plots of (t/q t ) vrsus t. Th plots for psudo-scond-ordr modl ar prsntd in Figur. (6). Th paramtrs for psudo-first and psudo-scond ordr modls ar all shown in (Tabl 2). As shown in Tabl (2), according to th corrlation cofficints (R 2 ), th calculatd q valu of psudo-scond-ordr kintic modl is in good agrmnt with th xprimntal q valu and could bttr fit th adsorption of mtal ion on th rsin vry wll. Th adsorbnt systms can b wll-dscribd by th psudo scond-ordr kintic modl. Th phnomnon also implis that th chlating raction is th main adsorption mchanism of th adsorption procss [33]. Th initial adsorption rat (h) can b dtrmind from k 2 and q valus using h = kk 2 qq2 (5) Th intra-particl diffusion modl was usd to tst whthr th adsorption rat is controlld by th diffusion mchanism. Th linar form intra-particl diffusion kintic modl basd on th thory or quation proposd by Wbr and Morris is tstd [21, 34]. Th adsorbat uptak varis almost proportionally with t 1/2 according to th following Wbr Morris s quation: qq tt = kk iidd tt 1/2 + CC (6) Whr k id is th rat paramtr of stag i (mg/g h 1/2 ), calculatd from th slop of th straight lin of qt vrsus t 1/2. C i is th intrcpt of stag i, giving an ida about th thicknss of boundary layr. That is to say, th largr th intrcpt indicats th gratr th boundary layr ffct. (4) Tabl 2. Paramtrs for psudo-first and psudo-scond ordr Mtal ions Cd Cu Pb Psudo first ordr Psudo Scond ordr Intraparticl diffusion K 1 (min -1 ) R 2 q K 2 (gmg -1 min -1 ) R 2 K int SMA-EthDA SMA-HmDA SMA-EthDA E SMA-HmDA E SMA-EthDA E SMA-HmDA E

6 60 Eman Abo-Bakr t al.: Modifid Poly (Styrn Malic Anhydrid) Copolymr for th Rmoval of Toxic Mtal Cations from Aquous Solutions Figur. 7 rprsnts a linar fit of intra-particl diffusion modl for adsorption of havy mtal ions onto SMA modifid copolymr. Th multi-linarity plot indicats thr stps of diffusion. Figur 7. Plots for intra-particl diffusion First, th mtal ions wr rapidly transportd from solution, du to th high initial havy mtal ion concntration and th availability of adsorbing sits on th surfacs of modifid SMA. Th sharpnss of this rgion is oftn assumd to b attributd to th high diffusion of adsorbat through th solution to th xtrnal surfac of adsorbnt [35]. Thn this stp is followd by a much slowr rgion II. At this stag, th diffusion rsistanc incrass [36] and consquntly th adsorption dcras lading to a lowr and lowr diffusion rat. Th third rgion is th final quilibrium stag whr intra-particl diffusion furthr slows down bcaus of th low concntrations of havy mtal ions lft in th solutions [37]. Tabl (3) lists valus of k d1 k d2 and k d3 for adsorption of Cd (II), Cu (II) and Pb (II) by modifid SMA. As xpctd, it was found that k d1 > k d2 for all mtal ions. Th rat of xtrnal surfac adsorption (th first rgion) of Pb(II) is highr than that th othr ions with SMA-EthDA and SMA-HmDA bcaus Pb (II)ion has th strongst binding affinity with ligand and th smallst hydratd ionic radius, which lad to th highst priority to b absorbd Adsorption Isothrms* Isothrm data wr applid to two adsorption modls and th rsults of thir linar rgrssion wr usd to find out th modl which bst fit th obtaind data. Valus of th rsulting paramtrs and th rgrssion cofficints (R 2 ) ar listd in Tabl 4. Tabl 3. Intra-particl diffusion modl constants and corrlation cofficints for adsorption of mtal ions on modifid SMA Mtal Ions K d1 (mg/g min 1/2 ) K d2 (mg/g min 1/2 ) K d3 (mg/g min 1/2 ) Intra-particl diffusion modl C 1 C 2 C 3 (R 1 ) 2 (R 2 ) 2 (R 3 ) 2 Cd Cu Pb SMA-EthDA SMA-HmDA SMA-EthDA SMA-HmDA SMA-EthDA SMA-HmDA Tabl 4. Isothrm modl paramtrs for th adsorption of mtal ion on th modifid SMA Mtal ion Cd Cu Pb Langmuir Frundlich Q max (mg g 1 ) K L (Lmg 1 ) R 2 R L n K F R 2 SMA-EthDA SMA-HmDA SMA-EthDA SMA-HmDA SMA-EthDA SMA-HmDA

7 Amrican Journal of Polymr Scinc 2015, 5(3): Th Langmuir isothrm modl is drivd to modl th assumptions of monolayr adsorption, a crtain numbr of idntical activ sits, activ sits distributd vnly on th surfac of th adsorbnt, and no intraction btwn adsorbnts [38]. Th quation for th Langmuir isothrm is as follows: C C 1 = + (7) q Qmax K LQmax whr C is th quilibrium concntration of mtal ions in solution (mg/l), q th adsorbd valu of mtal ions at quilibrium concntration (mmol/g), Q max (mg/g) and K L (l/mg) ar th Langmuir constants which ar rlatd to maximum adsorption capacity of adsorbnts (mg g 1 ) and nrgy of adsorption (mg L 1 ), rspctivly, and can b calculatd from th intrcpt and slop of th linar plot, with C /q vrsus C. Th ssntial charactristics of th Langmuir quation can b xprssd in trm of a dimnsionlss sparation factor, RL dfind as follows [39 41] 1 RR LL = 1+KK LL CC (8) 0 Whr C o is th highst initial solut concntration, and K L is th Langmuir s adsorption constant (L/mg). From Tabl (4), it can b found th valus of R L wr in th rang of 0 1, confirming th favorabl uptak of ths havy mtal ions. Th Frundlich isothrm is proposd basd on multilayr adsorption and adsorption on htrognous surfacs, which can b illustratd as [42]: q = K 1/ n Whr q and C ar quilibrium concntration of mtal ion in adsorbnt (mg/g) and liquid phas (mg/l), rspctivly. K F and n ar th Frundlich constants. Th linarizd quation taks th form: (9) (10) Whr K F and n ar th Frundlich constants, which rlatd to adsorption capacity of adsorbnt and th adsorption strngth, rspctivly. K F and n can b obtaind from th intrcpt and th slop of th linar plot of ln q vrsus ln C. Th Frundlich modl assums htrognous adsorption du to th divrsity of th adsorption sits or th divrs natur of th mtal ions adsorbd, fr or hydrolyzd spcis [40]. Tabl 4 displays th cofficints of th Langmuir and Frundlich modls along with rgrssion cofficints (R 2 ). As sn from Figur.8 and 9., th R 2 valus wr abov 0.90 for both th Langmuir and Frundlich isothrm modls, suggsting that both modls closly fit th xprimntal rsults. Howvr, th R 2 valus indicat that th Langmuir isothrm fit th xprimntal data bttr than th Frundlich F C 1 ln q + n = ln C ln K F at room tmpratur. Th maximum adsorption capacity of th monolayr (Q m ) valus for Cu(II) was highr than thos of Cd (II) and Pb (II), showing th following ordr: Cu (II) > Pb (II) > Cd (II). Figur 8. Langmuir adsorption isothrm for (a) SMA-EthDA and (b) SMA-HmDA Figur 9. Adsorption isothrm for (a) SMA-EthDA and (b) SMA-HmDA

8 62 Eman Abo-Bakr t al.: Modifid Poly (Styrn Malic Anhydrid) Copolymr for th Rmoval of Toxic Mtal Cations from Aquous Solutions 3.5. X-ray Diffraction Th dgr of crystallinity of th sampls was dtrmind by th known procdurs [43, 44]. Th structural proprtis of modifid SMA and th adsorbd mtal ion wr studid in th rang 2 Ө = o Th dgr of crystallinity, χ cr, is frquntly dtrmind from th ratio of th intgral intnsity of th pak of th crystallin rgions in th diffraction pattrn to th total intgral pak. To calculat th intnsity of th pak originating from th crystallin rgions in th sampls, th total ara undr th diffraction curv S tot and th ara of th amorphous componnt Sam wr dtrmind graphically. Th dgr of crystallinity, χ cr, was calculatd by th following xprssion: Stot Sam Χ cr = x(100) (10) S Whr S tot is th total ara undr th diffraction curv in th angl rang 4 o -90 o and Sam, th ara of th amorphous componnt in th sam rang. Th dgrs of crystallinity valuatd by th abov procdur ar shown in Figur10 and listd in th tabl (5). Th main pak in th XRD pattrn of SMA is obsrvd at 2 Ө = o. In th cas of this pak is shiftd to 2 Ө = o and o for SMA-EthDA and SMA-HmDA, rspctivly. tot Tabl 5. Crystallinity prcntag of th prpard polymrs with and without mtals Sampl Th dgr of crystallinity% d (A o ) SMA SMA - EthDA SMA - Eth DA-Cd SMA - EthDA-Cu SMA - EthDA-Pb SMA - HmDA SMA - HmDA-Cd SMA - HmDA-Cu SMA - HmDA-Pb It should b notd that th wak paks obsrvd in th XRD pattrns of th SMA ar absnt in th XRD pattrns of SMA-EthDA and SMA-HmDA. Th incorporation of mtal ion incrass th dgrs of crystallinity Pb(II)> Cd(II) >Cu(II). 4. Conclusions Th modifid styrn-co-malic copolymr hav bn succssfully prpard by th raction of two diffrnt alkyl diamin with SMA copolymr, and was usd for th adsorption of Cd (II), Cu (II) and Pb (II) from aquous solutions. Th rsults suggst that th adsorption is influncd by solution ph, initial concntration of th mtal ions and contact tim. Th xprimntal data wr wll fittd by th Langmuir isothrm modl and th adsorption cofficints agrd wll with th conditions supporting favorabl adsorption. Th adsorption kintics was found to fit th psudo scond- ordr kintics vry wll with rapid initial sorption rat. Th raction of th SMA copolymr with diamins lads to mor thrmally stabl products. REFERENCES [1] Nwuch, C.O., and Ugoji, E.O., 2008, Effcts of havy mtal pollution on th soil microbial activity, Int. J. Environ. Sci. Tchnol. 5(3), [2] Strnbrg, S.P.K., and Dorn, R.W., 2002, Cadmium rmoval using Cladophora in batch, smi-batch and flow ractors, Biorsourc Tchnology 81(3), [3] Liang, X., Su, Y., Yang, Y., and Qin, W., 2012, Sparation and rcovry of lad from a low concntration solution of lad (II) and zinc (II) using th hydrolysis production of poly styrn-co-malic anhydrid, Journal of hazardous matrials 203, Figur 10. (a) SMA (b)sma-ethda(c) SMA-EthDA-Cd (d) SMA-EthDA-Cu () SMA-EthDA-Pb (f)sma-hmda(g) SMA-HmDA-Cd (h) SMA-HmDA-Cu (i) SMA-HmDA-Pb [4] Bown, Humphry John Moul, Environmntal chmistry of th lmnts, Acadmic Prss, [5] Yu, B., Zhang, Y., Shukla, A., Shukla, S.S., and Dorris, K.L.,

9 Amrican Journal of Polymr Scinc 2015, 5(3): , Th rmoval of havy mtals from aquous solutions by sawdust adsorption rmoval of lad and comparison of its adsorption with coppr, Journal of hazardous matrials 84(1), [6] Lyva-Ramos, R., Rangl-Mndz JR, Mndoza-Barron, J., Funts-Rubio, L., and Gurrro-Coronado, R.M., 1997, Adsorption of cadmium (II) from aquous solution onto activatd carbon, Watr Scinc and Tchnology 35(7), [7] Emongor, V., 2007, Biosorption of lad from aquous solutions of varid ph by kal plants (Brasicca olraca varacphala), Journal of Agricultural, Food and Environmntal Scincs 1(2), [8] Madadrang, C.J., Kim, H.Y., Gao, G., Wang, N., Zhu, J., Fng, H., Gorring, M., Kasnr, M.L., Hou, S.F, 2012, Adsorption bhavior of EDTA-graphn oxid for Pb (II) rmoval, ACS Appl. Matr. Intrfacs 4, [9] Liu, D.G., Li, Z.H., Li, W., Zhong, Z.R., Xu, J.Q. J.J. Rn, Z.S. Ma, 2013, Adsorption bhavior of havy mtal ions from aquous solution by soy protin hollow microsphrs, Ind. Eng. Chm. Rs. 52, [10] Zhao, G., Wu, X., Tan, X., and Wang, X., 2011, Sorption of havy mtal ions from aquous solutions: a rviw, Opn Colloid Scinc Journal 4, [11] Chn, J. H., Hsu, K.C., Chang, Y. M., 2013, Surfac modification of hydrophobic rsinwith tricaprylmthylammonium chlorid for th rmoval of trac hxavalnt chromium, Ind. Eng. Chm. Rs. 52 (2013) [12] Othman, M.K., Al-Qadri, F.A., and Al-Yusufy, F.A., 2011, Synthsis, physical studis and uptak bhavior of: Coppr (II) and lad (II) by Schiff bas chlating rsins, Spctrochimica Acta Part A: Molcular and Biomolcular Spctroscopy 78(5), [13] Wang, Y.P., Shn, Y.Q., Pi, X.W., Zhang, S.C., Liu, H.G., Rn, J.M., In situ synthsis of poly(styrn-co-malic anhydrid)/sio2 hybrid composits via grafting onto stratgy basd on nitroxid-mdiatd radical polymrization, Ract. Funct. Polym. 68 (2008) [14] Krügr, S., Krahl, F., Arndt, K.F., 2010, Random cross-linkd poly(styrn-co-malicanhydrid): charactrization of cross-linking intrmdiats by siz xclusion chromatography, Eur. Polym. J. 46, [15] Qi, X.-H., Jia, X.-Q., Ying, Y., Niu, L.-E., and Hou, L.-P., 2010, Rcovry of nickl from mixd solution containing light mtals by PSt/MA rsin, Transactions of Nonfrrous Mtals Socity of China 20, s102. [16] McClain, A.R., and Hsih, Y.-L., 2004, Synthsis and mtal complxation of dihydroxyphosphino-functionalizd crosslinkd styrn/malic anhydrid copolymrs, J. Polym. Sci. A Polym. Chm. 42(1), [17] Lin, J.-J., and Hsu, Y.-C., 2009, Tmpratur and ph-rsponsiv proprtis of poly (styrn-co-malic anhydrid)-grafting poly (oxypropyln)-amins, Journal of colloid and intrfac scinc 336(1), [18] Gont, R.R., and Balasubramanian, K., 2012, Chmically modifid polymr bads for sorption of gold from wast gold solution, Journal of hazardous matrials 217, [19] Zhu, Z., Sun, F., Yang, L., Gu, K., Li, W., 2013, Poly (styrn-co-malic anhydrid) microsphrs prpard in thanol/ watr using a photochmical mthod and thir application in Ni 2+ adsorption, Chmical Enginring Journal 223, [20] Wi, K., Wu, J., Chn, Y., Hsu, Y., and Lin, J., 2007, Easy prparation of crosslinkd polymr films from polyoxyalkyln diamin and poly (styrn malic anhydrid) for lctrostatic dissipation, Journal of applid polymr scinc 103(2), [21] Ma, X., Li, L., Yang, L., Su, C., Wang, K., Yuan, S., and Zhou, J., 2012, Adsorption of havy mtal ions using hirarchical CaCO 3 maltos mso/macroporous hybrid matrials: Adsorption isothrms and kintic studis, Journal of hazardous matrials 209, [22] Bruch, M., Mädr, D., Baurs, F., Loontjns, T., and Mülhaupt, R., 2000, Mlt modification of poly (styrn co malic anhydrid) with alcohols in th prsnc of 1, 3 oxazolins, Journal of Polymr Scinc Part A: Polymr Chmistry 38(8), [23] Haidr, S., and Park, S.-Y., 2009, Prparation of th lctrospun chitosan nanofibrs and thir applications to th adsorption of Cu (II) and Pb (II) ions from an aquous solution, Journal of Mmbran Scinc 328(1), [24] Ngah, W.W., Endud, C.S., and Mayanar, R., 2002, Rmoval of coppr (II) ions from aquous solution onto chitosan and cross-linkd chitosan bads, Ractiv and Functional Polymrs 50(2), [25] Guibal, E., Ruiz, M., Vincnt, T., Sastr, A., and Navarro-Mndoza, R., 2001, Platinum and palladium sorption on chitosan drivativs, Sparation Scinc and Tchnology 36(5-6), [26] Justi, K.C., Fávr, V.T., Laranjira, M.C.M., Nvs, A., and Pralta, R.A., 2005, Kintics and quilibrium adsorption of Cu (II), Cd (II), and Ni (II) ions by chitosan functionalizd with 2 [-bis-(pyridylmthyl) aminomthyl]-4-mthyl-6-form ylphnol, Journal of colloid and intrfac scinc 291(2), [27] Wang, L., Xing, R., Liu, S., Yu, H., Qin, Y., Li, K., Fng, J., Li, R., and Li, P., 2010, Rcovry of silvr (I) using a thioura-modifid chitosan rsin, Journal of hazardous matrials 180(1), [28] Ho, Y.-S., 2006, Scond-ordr kintic modl for th sorption of cadmium onto tr frn: a comparison of linar and non-linar mthods, Watr rsarch 40(1), [29] Ho, Y.-S., and McKay, G., 2000, Th kintics of sorption of divalnt mtal ions onto sphagnum moss pat, Watr rsarch 34(3), [30] Wbr, W.J., and Morris, J.C., 1963, Kintics of adsorption on carbon from solution, Journal of th Sanitary Enginring Division 89(2), [31] Wang, P., Du, M., Zhu, H., Bao, S., Yang, T., and Zou, M., 2015, Structur rgulation of silica nanotubs and thir adsorption bhaviors for havy mtal ions: ph ffct, kintics, isothrms and mchanism, Journal of hazardous matrials 286, [32] Donia, A.M., Atia, A.A., and Elwakl, K.Z., 2008, Slctiv

10 64 Eman Abo-Bakr t al.: Modifid Poly (Styrn Malic Anhydrid) Copolymr for th Rmoval of Toxic Mtal Cations from Aquous Solutions sparation of mrcury (II) using magntic chitosan rsin modifid with Schiff's bas drivd from thioura and glutaraldhyd, Journal of hazardous matrials 151(2), [33] Hua, M., Jiang, Y., Wu, B., Pan, B., Zhao, X., and Zhang, Q., 2013, Fabrication of a nw hydrous Zr (IV) oxid-basd nanocomposit for nhancd Pb (II) and Cd (II) rmoval from watrs, ACS applid matrials & intrfacs 5(22), [34] Wbr, W.J., and Morris, J.C., 1962, Procding of th Intrnational Confrnc on Watr Pollution Symposium, Prgamon Prss, Oxford 2, [35] Sadghi, S., Rad, F.A., and Moghaddam, A.Z., 2014, A highly slctiv sorbnt for rmoval of Cr (VI) from aquous solutions basd on F 3 O 4/poly (mthyl mthacrylat) graftd Tragacanth gum nanocomposit: Optimization by xprimntal dsign, Matrials Scinc and Enginring: C 45, [36] Mututuvari, T.M., and Tran, C.D., 2014, Synrgistic adsorption of havy mtal ions and organic pollutants by supramolcular polysaccharid composit matrials from cllulos, chitosan and crown thr, Journal of hazardous matrials 264, [37] Tan, I.A., Ahmad, A.L., and Hamd, B.H., 2009, Adsorption isothrms, kintics, thrmodynamics and dsorption studis of 2, 4, 6-trichlorophnol on oil palm mpty fruit bunch-basd activatd carbon, Journal of hazardous matrials 164(2), [38] Wang, J., Zhou, Y., Li, A., and Xu, L., 2010, Adsorption of humic acid by bi-functional rsin JN-10 and th ffct of alkali-arth mtal ions on th adsorption, Journal of hazardous matrials 176(1), [39] Ramsh, A., Hasgawa, H., Sugimoto, W., Maki, T., and Uda, K., 2008, Adsorption of gold (III), platinum (IV) and palladium (II) onto glycin modifid crosslinkd chitosan rsin, Biorsourc Tchnology 99(9), [40] Wang, X., Zhang, Y., and Li, Q., 2011, Charactrization and dtrmination of th thrmodynamic and kintic proprtis of th adsorption of molybdnum (VI) onto microcrystallin anthracn modifid with 8-hydroxyquinolin, Matrials Scinc and Enginring: C 31(8), [41] Hall, K.R., Eaglton, L.C., Acrivos, A., and Vrmuln, T., 1966, Por-and solid-diffusion kintics in fixd-bd adsorption undr constant-pattrn conditions, Industrial & Enginring Chmistry Fundamntals 5(2), [42] Jin, X., Li, Y., Yu, C., Ma, Y., Yang, L., and Hu, H., 2011, Synthsis of novl inorganic organic hybrid matrials for simultanous adsorption of mtal ions and organic molculs in aquous solution, Journal of hazardous matrials 198, [43] Chbotok, E.N., Novikov, V.Y., and Konovalova, I.N., 2007, Kintics of bas dactylation of chitin and chitosan as influncd by thir crystallinity, Russian Journal of Applid Chmistry 80(10), [44] I. Bouchr, K. Jamison, A. Rtnakaran, Advancs in Chitin Scinc, Vol7.(Montral: 9th ICCC), 2004.